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 THE CHEMICAL EXAMINATION 
 
 OF WATER, FUEL, 
 FLUE GASES AND LUBRICANTS 
 
 S. W. PARR 
 
".f V 
 
THE CHEMICAL EXAMINATION OF 
 
 WATER, FUEL, FLUE GASES 
 
 AND LUBRICANTS 
 
 A COURSE FOR ENGINEERING STUDENTS 
 
 CHEMISTRY 16 
 
 As given in the Division of Applied Chemistry at the 
 UNIVERSITY OF ILLINOIS 
 
 BY 
 
 S. W. PARR 
 Professor of Applied Chemistry 
 
 URBANA, ILLINOIS 
 1916 
 
COPYRIGHT 1911 
 COPYRIGHT 1916 
 BY S. W. PARR 
 
CONTENTS 
 
 PART I: LECTURES 
 
 Chapter I : Boiler Waters : PAGE 
 
 Source and character of mineral content 5 
 
 Effect of impurities 8 
 
 Chemical treatment 13 
 
 Apparatus for applying chemical processes 18 
 
 Rating of boiler waters 23 
 
 Type waters and calculated treatment 26 
 
 Chapter "ll : Fuels: 
 
 Types, relative values 27 
 
 Coal: 
 
 Properties, Classification 30 
 
 Sampling _ 32 
 
 Moisture, Calculations _ 43 
 
 Unit Coal, Corrected ash 46 
 
 Calorimetric measurements 49 
 
 Table of average values 60 
 
 Coal specifications and contracts 61 
 
 Combustion, Smoke 65 
 
 Storage, "Weathering 66 
 
 Chapter III : Flue Gases, Significance of analytical results 71 
 
 Calculation for heat losses 72 
 
 Chapter IV : : Lubricants, Types, Properties 76 
 
 PART II : LABORATORY METHODS- 
 
 Chapter V : Preliminary experiments 79 
 
 Standard solutions 80 
 
 Chapter VI : Boiler water analysis - 85 
 
 Summary and calculations _ _ 92 
 
 Chapter VII : Fuel Analysis, Proximate 94 
 
 Heat Values, Peroxide Calorimeter 97 
 
 Sulphur determination _ 103 
 
 Heat values, oxygen bomb 108 
 
 Calculations 114 
 
 Chapter VIII : Ultimate analysis 115 
 
 Total carbon by volume 117 
 
 Available hydrogen 119 
 
 Chapter IX : Flue gas analysis 120 
 
 Chapter X: Oil examination 122 
 
 Index . . 128 
 
 349279 
 
PRELIMINARY STATEMENT 
 
 This work is intended primarily for Juniors in Mechanical and 
 Railway Mechanical Engineering at the University of Illinois. From 
 the chemical standpoint, it is a very serious problem to know what may 
 profitably be attempted in the way of analytical methods in the case 
 of students whose chemical experience is meager. But, however unsat- 
 isfactory the amount of preliminary training, it is obvious that the 
 curriculum in Engineering courses is already overcrowded, hence the 
 obtaining of a better prerequisite in chemistry is well nigh impossible. 
 The work as herein outlined is the result of ten years of effort to make 
 the most of the situation. It would be quite too much to claim that in 
 the evolution of the work a satisfactory status has been attained. It 
 is hoped, however, that the course will at least help the engineer to a 
 better understanding of the literature of the topics considered and also 
 to an appreciation and, consequently, a more intelligent use of data 
 which may come into his hands from the chemist. It may not be out of 
 place to state further that the course, which, at the first, was inaugu- 
 rated with no little misgiving, has more than justified the experiment. 
 For this result credit is due the students, who, from year to year have 
 carried the work through with a responsiveness which has been the main 
 stimulus in developing this outline into its present form. 
 
 Part I is a synopsis only of the lectures given. Part II consists 
 essentially of laboratory directions for the analytical methods there 
 undertaken. The time allowance for lectures, quizzes, and laboratory 
 is nine hours per week for 18 weeks. The amount of work as outlined 
 is such that the average student covers the ground in the time prescribed. 
 
 Special acknowledgement is due Dr. H. J. Broderson for suggested 
 improvements in the present edition and for valued assistance in the 
 reading of proof. 
 
PART I 
 
 DESCRIPTIVE OUTLINE 
 
 CHAPTER I 
 
 BOILER WATERS 
 
 THEIR EXAMINATION, CHARACTER AND TREATMENT. 
 
 Water Analysis: Waters are examined for two very different 
 purposes. First, the object may be to determine the potability or 
 sanitary character of the water; and, second, it may be desired to 
 learn the behavior or value of the water for industrial uses. The require- 
 ments under each division are very different. In order to be sanitary, 
 a water must be free from certain forms of organic matter which might 
 indicate possible contamination with sewage or furnish a suitable breed- 
 ing medium for disease germs. Within reasonable limits, the amount of 
 mineral constituent is of little importance. On the contrary, however, 
 the value of a water for industrial purposes depends very largely on 
 the kind and amount of the dissolved mineral substance, while, as a rule, 
 little importance is attached to the organic material present. This is 
 especially true in the case of those waters which are to be used for 
 boiler purposes, and it is this phase of the subject which is of immediate 
 interest. 
 
 Source of the Mineral Constituents: Natural waters in passing 
 through the soil come in contact with certain products of decomposition 
 and decay. Some of these substances, notably carbon dioxide, humie 
 acid, etc., are taken up by the waters, in which condition their power 
 to dissolve mineral matter is greatly increased. In this way the decom- 
 position of feldspar, limestone, etc., is constantly going on, the result 
 to the percolated water being that there is taken into solution varying- 
 quantities of silica, salts of iron, aluminum, magnesium, sodium, 
 potassium, etc. As a rule, therefore, the less contact natural waters 
 have had with the soil, or the more insoluble the earthy matter with 
 which they have come in contact, the smaller will be the amount of 
 mineral constituents dissolved: and, conversely, the deeper the source 
 of supply, the greater the opportunity for dissolving such material, 
 and consequently the greater will be the amount of such substances in 
 
 5 
 
6 THE.\CHMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 solution. For this reason it has been sometimes customary to divide 
 waters into three classes : 
 
 First; Surface water, 
 
 Second; Shallow wells and spring waters, 
 
 Third; Deep wells and artesian waters. 
 
 Surface waters are such as are found in lakes, streams, and artificial 
 ponds, and with these might also be considered cistern or rain waters; 
 shallow well waters may be considered as those obtained from wells 
 or borings which extend into the drift not to exceed 30 or 40 feet; 
 while deep well waters may be considered those that are obtained from 
 a depth of over 100 feet. These divisions are not sharply drawn, and, 
 indeed, the classes merge into each other. This is more readily seen 
 from the fact that many streams, for a large part of the year at least, 
 are fed by waters which have their source in tile drains and springs. 
 The system of underground drainage so largely carried on in these 
 days, therefore, gives to the waters of smaller streams at least many 
 of the characteristics of the water from the shallow wells. This feature 
 is more pronounced during the dry months of the year, as, for example, 
 in the late summer and fall. The amount of mineral matter, therefore, 
 varies inversely as the volume of water in these minor streams. On 
 the other hand, large bodies of water and larger streams, especially 
 those -in districts where they come in contact with the more insoluble 
 formations, are remarkably free from mineral matter. This is especially 
 characteristic in the waters of Lake Superior, and in many of the rivers 
 of the north-central region of the United States. In certain regions, 
 also, as in the delta of the Mississippi, water-bearing sands are some- 
 times found at very considerable depths, but with extremely small 
 amounts of mineral matter present. 
 
 It will be seen from the above discussion that any classification 
 based merely upon the source of a water will have little practical value. 
 Before attempting any classification, however, based upon the character 
 of the dissolved mineral constituents it will be necessary to review the 
 processes by which these substances become a part of the water, and to 
 note their properties and behavior under the conditions of actual use 
 in steam boilers. 
 
 Chemical Characteristics of the Mineral Constituents : Calcium car- 
 bonate, CaC0 3 , and magnesium carbonate, MgC0 3 , are the chief consti- 
 tuents of lime rock. Finely divided particles of these substances exist 
 throughout all the clayey deposits of the drift region. The percolating 
 water holding carbon dioxide, C0 2 , in solution has the property of a 
 
SOLUTION PROCESSES 7 
 
 weak acid, H 2 + CO 2 = H 2 C0 3 , and in this form is a solvent for the 
 above substances, forming bicarbonates, thus: 
 
 CaC0 3 + H 2 C0 3 = CaH,(C0 3 ).> 
 MgC0 3 + H 2 C0 3 = MgH 2 (C0 3 ) 2 
 
 These dissolved bicarbonates are readily broken down by heat, 
 thus : 
 
 CaH 2 (CO 3 ), = CaC0 3 + H 2 + C0 2 
 
 The water alone with the carbon dioxide gas driven out of it is not 
 a solvent for calcium carbonate, and the latter is precipitated. 
 
 Feldspars of various sorts are usually distributed throughout the 
 drift deposits. These also are slowly decomposed by carbonated waters 
 thereby adding to the water compounds of sodium, potassium, iron and 
 aluminum, as well as hydra ted silica, which is also soluble. The general 
 type of this reaction may be shown, thus : 
 Al 2 3 .K 2 0.6Si0 2 + 2H 2 C0 3 == Al,O 3 .2Si0 2 .2H 2 + K 2 C0 3 + 4 Si0 2 
 
 FELDSPAR KAOLIN 
 
 In this way complex or impure rocks may, upon their decompo- 
 sition, yield small quantities not only of lime and magnesium in solution 
 as bicarbonates, but also iron in a bicarbonate form, as well as salts of 
 sodium, potassium, and silicic acid. This result would be more readily 
 understood if we were to enter into a study of the composition of the 
 drift, especially of a region like this where the glacial clay has a very 
 considerable admixture of ground rock such as feldspar, hornblend, 
 mica, dolomite, etc. Moreover, since all drift formation has been depos- 
 ited in contact with or by means of sea water, we expect a greater or 
 less amount of mineral substances to be present due to such water; 
 namely, sodium chloride, calcium sulphate, etc. 
 
 Solubility of Gypsum: We are familiar with the solubility of 
 sodium chloride, but calcium sulphate or gypsum is also soluble, 
 although to a less degree, and this without the aid of carbon dioxide. 
 Its solubility, for example, may be illustrated by the following table : 
 
 TABLE I 
 
 SOLUBILITY OF GYPSUM 
 (CaS0 4 +2H 2 0). 
 
 1 part dissolves in about 500 parts of water at ordinary temperature 
 1 part dissolves in about 1200 parts of water at 250 Degrees F. 
 1 part dissolves in about 1800 parts of water at 300 Degrees J 1 . 
 1 part dissolves in about 3800 parts of water at 325 Degrees F. 
 
8 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 From the above facts it may be readily understood how the mineral 
 constituents come to be dissolved in all underground waters. The kind, 
 amount, and properties of these substances indicate directly the behavior 
 of a water when used for boiler purposes. Almost without exception 
 their presence is objectionable for reasons which will be evident from 
 the following discussion. 
 
 Effects of Impurities: The difficulties which attend the use of 
 water in the generation of steam are three in number : 
 
 First, mineral scale is formed upon the shell, flues, and sheets; 
 second, foaming or priming may occur; and, third, the water may have 
 corrosive action and weaken the metal of which the boiler is composed. 
 
 The constituents of a water, therefore, naturally group themselves 
 under these three heads : 
 
 1. Scaling Ingredients. 
 
 2. Foaming Ingredients. 
 
 3. Corrosive Ingredients. 
 
 Scaling Ingredients: Scaling ingredients are always considered as 
 including silica and any combination of iron, aluminum, calcium, and 
 magnesium. Since the formation of scale is the most common and 
 perhaps the most evident difficulty which accompanies the use of a 
 boiler, it has sometimes been made the basis of a classification for 
 waters. At a meeting of the American Association of Railway Chem- 
 ists at Buffalo, New York, May 24, 1887, the following schedule of 
 classification was adopted. Waters containing varying quantities of 
 scaling material per United States gallon were graded as in the table 
 below : 
 
 TABLE II 
 
 CLASSIFICATION OF WATERS BY THE 
 ASSOCIATION OF RAILWAY CHEMISTS 
 
 Below 8 grains very good 
 
 8 to 15 grains - good 
 
 15 to 20 grains fair 
 
 20 to 30 grains poor 
 
 30 to 40 grains bad 
 
 over 40 grains very bad 
 
 In tfci$ table the first line was added by the C. B. & Q. By. to fit 
 the case of Lake Michigan water, which has approximately 8 grains or 
 less per gallon. 
 
EFFECT OF SCALE 9 
 
 This classification is relative only, since a wider study of the 
 subject has indicated the necessity of taking into the account the kind 
 of scale which would form and the other ingredients in addition to 
 those which produce scale. The scale when formed, may be dense and 
 flint-like or open and porous. These characteristics result from the 
 various types of mineral content involved. In general, a hard, flinty 
 scale is due to the presence of calcium or magnesium sulphates; while, 
 in waters in which only the carbonates of these substances are present, 
 the scale will be more open and friable. Indeed, a very large number 
 of waters are met with where only carbonate hardness is present. In 
 these cases the major part of the incrusting solids appears as mud or 
 sludge. For these and other reasons the above classification has not met 
 the needs of the case and has, indeed, not been adopted to any con- 
 siderable extent. A much more practical classification would take 
 account of all of the various constituents and the characteristics for 
 which they are responsible. The method of classification devised by the 
 Chicago, Burlington & Quincy Railroad is based on the amount of 
 these various constituents. Since the full meaning of the same can be 
 better understood later, it is reproduced at the end of this chapter. 
 
 Effect of Scale : Boiler scale is a disadvantage for the reason that : 
 First, it retards the transmission of heat ; second, it promotes the forma- 
 tion of a high temperature in the plates, with a possibility of softening 
 the same ; third, the sudden rupture or opening up of the scale may 
 admit water to the highly heated metal, forming hydrogen and oxygen ; 
 fourth, the higher temperature of the steel thus maintained, even though 
 not reaching the danger point, promotes the absorption of sulphur and 
 oxygen and thus causes a deterioration of the metal. Doubtless the 
 chief item in this list, by reason of its continuous and total aggregate 
 effect, is the decrease of heat conductivity, requiring a larger amount 
 of fuel. Authorities differ as to the extent of loss. A conservative 
 estimate would place the loss of fuel at 10% for each 1/16 of an inch 
 in thickness of the scale. The difficulties attending the estimation of 
 the fuel loss are great, and it is to be expected that a rather wide 
 range of results is found in the published data.* 
 
 A test of the steaming efficiency, made upon an Illinois Central 
 
 locomotive by the University of Illinois in 1898 and described in the 
 
 Railway Gazette for the following year, indicated a loss of heat, with a 
 
 *The effect of scale on the Evaporation of a Locomotive Boiler. By L. P. 
 
 Breckenridge. R. R. Gazette, Vol. 31, new series, p. 60, 1899. 
 
 Am. Ry. Eng. Asscn., 1914 p. 692 : " it is concluded that the saving 
 
 of $977- per locomotive represents 7 cents per pound of excess scaling matter enter- 
 ing the boiler ". 
 
 Bulletin No. 11, Eng. Exp. Sta., U. of I. 
 
 Am. Ry. Eng. & Maint. of Way Assn., Jan., 1907, p. 41, etc. 
 
io THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 scale averaging 3/64" in thickness, amounting to 9.6 per cent. The 
 same engine was tested before overhauling at the shops and was re- 
 turned after cleaning for the comparative test. An interesting compu- 
 tation was made on the same road at a much earlier date, in which 
 the performance sheets for 120 locomotives were taken with reference 
 to the comsumption of coal before overhauling, and these results were 
 compared with the coal consumed for the three months immediately 
 following such a cleaning, with an average for the 120 engines of almost 
 exactly 10 per cent in favor of the scale-free condition. Many other 
 tests have subsequently been made more or less confirmatory of these 
 results. 
 
 Foaming Ingredients: The non-scaling or foaming ingredients 
 are considered to be the salts of the alkalies, such as sodium chloride, 
 sodium sulphate, sodium carbonate, potassium chloride, potassium sul- 
 phate, potassium carbonate, etc. Other conditions contribute to the 
 tendency of water to foam, such as the presence of organic matter, 
 especially such substances as may form soap. The presence of finely 
 divided solids in suspension is also a contributing cause. 
 
 The objections against foaming may be states as follows: First, 
 the rising of the water in the gauge glass or blow off cocks makes it 
 difficult, if not impossible, to know the height of the water in the boiler ; 
 second, the discharge of wet steam or of steam carrying a considerable 
 Quantity of water is exceedingly wasteful of heat and makes it difficult 
 to keep up the steam pressure; third, there is danger of large quanti- 
 ties of water getting into the cylinders where, by reason of its incom- 
 pressibility and inability to pass quickly out of the ports, a cylinder 
 head may thereby be blown off; and, fourth, the grit carried along with 
 the water promotes the cutting of the walls of the cylinders and valve 
 seats, thus making a re-boring of the cylinders necessary. 
 
 Concerning the causes which promote foaming, they are not so 
 easy to define or classify as in the case of scaling, and they do not always 
 relate directly to the character of the dissolved mineral substance. The 
 tendency to foam varies greatly, for example, with the two general types 
 of boilers employed, those used for stationary purposes, and the loco- 
 motive type. It might be said, indeed, that to the above mentioned 
 conditions of the water might be added the nature of the spaces in 
 which the generation of steam takes place. A net- work of stay-bolts 
 and braces in a steaming space of small volume at best will be more 
 conducive to foaming than the opposite conditions. The structure and 
 steaming capacity of the locomotive, therefore, greatly increase the ten- 
 dency of this type of boiler to foam. Tests on numerous railroads pretty 
 generally agree upon the following facts concerning the foaming in loco- 
 
CORROSIVE INGREDIENTS 11 
 
 motives. When a density of the water due to the presence of alkali 
 sulphate or chloride reaches approximately 100 grains to the gallon, 
 foaming is apt to occur, especially when the engine is put under 
 heavy work. This means that in the raw water, before condensation 
 has been carried on, a content of 25 grain per gallon would reach the 
 foaming stage when 3 or 4 tankfuls had been taken into the boiler. 
 However, a wide variation is due to the type of foaming ingredients, 
 since a less amount of alkali salt will cause foaming where part 
 of the substance is alkali carbonate, Na 2 C0 3 , or soda ash. Where 
 much organic matter also is present, a still less amount of free alkali 
 will cause foaming. Indeed, cases have been met with where 15 to 25 
 grains per gallon of alkali salts have produced foaming, when one-half, 
 for example, of such salts were in the form of alkali carbonates, ac- 
 companied by a very considerable amount of organic matter. Foaming 
 in stationary boilers would scarcely be caused by double the amount 
 mentioned above. 
 
 Corrosive Ingredients: Much disagreement exists regarding the 
 causes of corrosion. Certain conditions will produce galvanic action 
 between different metals used in construction, or even between different 
 parts though made of the same metal, and this action eats away the 
 metallic surfaces. Flaw r s, cinder scales, oxide nodules, etc., will, prob- 
 ably for a similar reason, produce pitting. Along sharp angles of con- 
 struction, w r here the metal has been put under strain, corrosion will 
 frequently occur. Carbonic acid gas or oxygen, when dissolved in water, 
 are solvents for iron. Of course, the heat soon drives these gases out of 
 the water, but corrosion in the vicinity of the feed inlet may be due 
 to this cause. Some waters percolate through culm heaps or coalmine 
 refuse or drainage and have produced in them free sulphuric acid 
 from the oxidation of iron pyrites, or they may take up sulphate of iron 
 or aluminium, all of which chemicals render a water positively and 
 vigorously corroding. 
 
 Nitrates are seldom encountered, but, when present in any consider- 
 able amount, are strongly corroding. Calcium and magnesium chlorides 
 are also strongly corroding. But, after all, it may be noted that many 
 conditions can exist to neutralize the corrosiveness of a water. For 
 instance, there may be formed a hard, dense scale which will effectually 
 protect the iron. In this case, however, we would expect to see some 
 tendency toward corrosion and pitting under the scale. 
 
 If, now, we attempt to classify waters according to the mineral 
 constituents above outlined, we would have : 
 
 Class I. This class includes such waters as have present free sodium 
 carbonate or more than enough sodium to unite with the sulphate, 
 
12 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 chloride, and nitrate radicals or ions. There would be left, therefore, 
 only carbon dioxide, C0 2 , to unite with the remaining sodium and also 
 the calcium, magnesium, and iron. Such waters have only temporary 
 hardness, there being no sulphates of calcium or magnesium. Upon 
 boiling or using in the steam boiler, only a sludge forms instead of 
 scale. The carbonates are all in the bicarbonate form and, hence, are 
 stable in the cold, but decompose upon heating. Waters of this class are 
 very widely distributed throughout the drift region, and the source is 
 usually from deep wells. 
 
 Class II. The waters of this class contain calcium or magnesium 
 sulphate as well as bicarbonates, but not the chlorides of these elements. 
 They have, therefore, permanent hardness and form a hard, flinty 
 scale. Such waters are usual in surface supplies and in most shallow 
 wells. 
 
 Class III. This includes such waters as contain corroding salts 
 or free acid in solution, such as the chlorides or nitrates of magnesium 
 or calcium, the sulphate of iron or free sulphuric acid. Such waters 
 are infrequent but, because of their corroding character, should be 
 recognized when met with. . ' 
 
 The Chemical Treatment of Boiler Waters: From what has pre- 
 ceded it will be readily understood that the treatment of boiler waters 
 must follow closely along the line of the chemical character of dissolved 
 ingredients, with a view also to the properties which various ingredients 
 impart to the water. In the first instance, it must be remembered that 
 all natural water is strongly impregnated with carbon dioxide. We 
 should recall again the fact that the presence of this gas in the water 
 has furnished a solvent condition which has resulted in the formation of 
 bicarbonates, especially of lime, magnesium, and iron. 
 
 But other soluble substances, we have already seen, also enter into 
 the water, notably the sulphates of lime, magnesium, sodium, etc. Now, 
 because of the fact that the compounds of the first group of substances 
 are easily decomposed by heat and thus discharged from solution, we 
 have a sub-division of scaling ingredients into 
 
 (A) Those which are designated as constituting temporary hard- 
 ness and (B) Those which constitute permanent hardness of water. The 
 first division is present in all waters and includes the larger part of the 
 scaling matter; the latter is variable in amount and frequently absent, 
 so far as the scaling constituents are concerned. These two general 
 divisions or types of scaling material must be borne in mind, because 
 they form the basis of all practical methods for water treatment, indeed, 
 each division represents a process or a method which must be followed 
 
SCALING MATERIAL AND ITS REMOVAL 
 
 for the removal of these substances, 
 trated by the following outline: 
 
 This may be more clearly illus- 
 
 TABLE III 
 SCALING MATTER AND TREATMENT 
 
 
 'Div. I. 
 
 -LJ.A.UCQO V^V 
 
 
 Bicarbon-* 
 
 CaH,(C0 3 ) 2 
 
 Scaling 
 
 ates as : 
 
 Mg 
 
 matter 
 
 
 "R^o * ' 
 
 is prin- ^ 
 
 
 cipally 
 
 
 
 com- 
 posed of 
 
 Div. II. 
 
 Sulphates, 
 
 MgSo, 
 
 Ca " 
 
 
 as: 
 
 Fe 
 
 For this 
 Div. use 
 
 The 
 results are 
 
 CaC0 3 +2H 2 
 
 CaC0 3 +CaC0 3 -f2H 
 
 MgC0 3 +CaCO a +2H 
 
 ^FeC0 3 *+CaC0 3 +2H 2 
 
 MgC0 3 +Na 4 SO 
 CaC0 3 +Na 2 S0 4 
 
 FeCO* 3 +Na 2 S0 4 
 
 For this 
 Div. use 
 NaoC0 3 . 
 
 fThe 
 results 
 are 
 
 *This substance quickly breaks down into Fe(OH) 8 thus: 
 2FeCOa + 3H 2 + O = 2Fe(OH) 8 + 2CO 2 
 
 It will be readily seen from this outline that the first division, carry- 
 ing the bicarbonates, may be removed from the water either by heat or by 
 the addition of some chemical which will absorb the ' * excess ' ' and ' ' bicar- 
 bonate" carbon dioxide. If we were to depend upon heat for this work, it 
 would be a long process for the reason that ordinarily these bicarbonates 
 are not completely broken down except upon rather prolonged boiling, 
 say for 15 or 20 minutes or even % hour, and this again would indicate 
 the impracticability of such a method, because of the expense involved. 
 
 Treatment with Lime, Ca(OH)^: Since hydrated lime reacts at 
 ordinary temperatures and, moreover, is the least expensive of the 
 possible reagents, it is made use of to react with the C0 2 of Div. I of 
 Table III. 
 
 In measuring the amount of Ca(OH) 2 needed for treating a water, 
 it must be borne in mind that the C0 2 dissolved as H,C0 3 will react 
 with the Ca(OH) 2 the same as the bicarbonates. Hence we have a series 
 of reaction thus: 
 
 a H 2 C0 3 
 
 fCaH,(C0 3 ) 2 
 
 b ^MgH 2 (C0 3 ) 2 
 
 lFeH 2 (C0 3 ) 2 
 
 CaC0 3 + 2H,0 
 
 CaCO 3 + CaC0 3 
 MgC0 3 + CaCOo 
 FeC0 3 + CaC0 3 
 
14 THE CHEMICAL EXAMINATION OF WATER, FUEL; ETC. 
 
 The total C0 2 to be thus taken care of is designated as (a) "excess'* 
 or "free" carbon dioxide, and (&) "half bound" or "bicarbonate" 
 carbon dioxide. It is necessary to measure the amount of free carbon 
 dioxide by titrating, say 200 c.c. of the water with N / 50 Na 2 C0 3 , using 
 phenolphthalein as indicator. Each c.c. of this reagent, therefore, 
 represents an equivalent of 0.001 gram in terms of CaC0 3 .* 
 
 Therefore, 5 times the number required for 200 c.c. of water would 
 represent the equivalent in 1000 c.c. or 1 liter of water. This would 
 represent milligrams per liter which is the same as parts per million. 
 Parts per million multiplied by 0.0583 = grains per gallon.** 
 
 The "bicarbonate" carbon dioxide is determined by titrating a 
 measured volume of the water with N / 10 sulphuric acid, using methyl 
 orange as indicator. (See p. 86, Part II.) Each cubic centimeter of 
 N / 10 sulphuric acid is equivalent to 0.005 gram CaC0 3 . Therefore, if 
 200 c.c. of water be titrated, each c.c. of acid used corresponds to 0.025 
 grams, that is 25 milligrams per liter or 25 parts per million bicar- 
 bonate carbon dioxide, measured in terms of CaC0 3 . 
 
 The above estimation of the "free" and "half bound" carbon 
 dioxide would represent all of the conditions to be taken into consid- 
 eration in connection with the lime treatment except for the slight 
 irregularity in the behavior of one element. The magnesium carbonate, 
 especially in the presence of other salts, is soluble to an extent which 
 makes it advisable to carry the reaction one step further and provide 
 for the formation of magnesium hydroxide which compares favorably as 
 to insolubility with the calcium carbonate. This is effected by adding 
 enough extra Ca(OH) 2 to correspond to the magnesium present. By 
 direct determination, therefore, of the magnesium and the calculation 
 of the same to the calcium carbonate equivalent, we have the necessary 
 correction indicated for this element. By adding the calcium carbonate 
 equivalent thus found to the factor as derived above by titration with 
 N /V sulphuric acid, we have a corrected calcium carbonate equivalent 
 for the bicarbonate carbon dioxide plus the magnesium present. 
 
 Having thus determined the amount of ' ' excess ' ' and ' ' half bound ' ' 
 carbon dioxide plus the magnesium, in terms of CaCO 3 , the amount 
 of reagent as CaO for the total CaC0 3 equivalent would be in the ratio 
 of 56 : 100. To transfer to a unit of 1000 gallons, multiply values for 
 1 gallon by 1000; and to transfer grains to pounds avoirdupois, divide 
 
 *The molecular weight of CaCO 5 is 100. This is a bivalent molecule, hence the 
 univalent or hyrdogen equivalent would be 50. and the N/5o value would be I. gram 
 per looo. c.c. Hence I c.c. would have a CaCOs equivalent of o.ooi gram. 
 
 **One gallon weighs 58330 grains hence 1/1,000,000 of a gallon or i part per 
 million weighs .0583 grains. 
 
USE OF LIME AND SODA ASH 15 
 
 by 7000. Hence, '1/7 of 56 /ioo or -08 times the grains per gallon of total 
 calcium carbonate equivalent represents the pounds of CaO reagent 
 needed for each 1000 gallons of water in removing or correcting for 
 these ingredients. 
 
 In the case of common or commercial reagents used in water treat- 
 ment, the impurities, of course, must be allowed for. 
 
 Where the lime is added in the form of a clear solution of Ca(OH) 2 , 
 the latter is dissolved to the point of saturation and this concentrated 
 solution becomes the reagent. 
 
 The solubility of CaO is about 78 grains per gallon cold, (60F). 
 
 7000 
 Hence l/78th gallon of lime water contains 1 grain of CaO, and no 
 
 /o 
 
 would represent the number of gallons necessary to hold 1 pound of 
 CaO in solution. Therefore, 
 
 Xo. gals, of sat. lime 
 water required to remove 
 
 or 7-17+ = the total calcium carbon - 
 
 of CaCOa ate equivalent in I000 
 
 equivalent gallons of 
 
 The solubility of CaO decreases as the temperature of the water 
 increases. It should be remembered, also, that CaO slakes to Ca(OH) 2 
 and it is really the solubility of the latter compound which is involved. 
 Usually, however, the reference is made to the solubility of CaO as the 
 basis. Thus, by calculating from Lamy's tables (C. E. Vol. 86, p. 333), 
 
 78 grains CaO will saturate one U. S. gallon at 60 F. 
 
 70 grains CaO will saturate one U. S. gallon at 86 F. 
 
 58 grains CaO will saturate one U. S. gallon at 112 F. 
 
 51 grains CaO will saturate one U. S. gallon at 140 F. 
 
 33 grains CaO will saturate one U. S. gallon at 212 F. 
 
 Recently the market has come to be supplied with pulverized dry 
 lime in the hydrated form. To find the solubility by weight of this 
 material, calculate the above amounts to the equivalent of Ca(OH) 2 . 
 Thus, 
 
 56 : 74 :: 78 : x 
 
 CaO Ca(OH) 2 gr.CaO gr.Ca(OH), 
 
 Whence, 78 grains CaO = 103 grains Ca(OH) 2 , which would rep- 
 resent the solubility per gallon at 60 F. of pure material. 
 
 Treatment with Soda Ash, Na 2 CO z . Of the substances sufficiently 
 cheap to be available, sodium carbonate or ''soda ash" is by far the 
 
16 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 best adapted for division II of Table III, or those ingredients causing 
 the permanent hardness of the water. No reaction or change in solubil- 
 ity by heating can be effective, though many attempts to remove the 
 sulphate by reason of the less solubility of calcium sulphate in hot water, 
 (as indicated in Table No. I), have been attempted. With this class 
 of substances, it is more effective to remove them as carbonates, but 
 this must be brought about by the addition of a soluble carbonate salt, 
 the cheapest of which is sodium carbonate or "soda ash", Na 2 C0 3 , as 
 above indicated. 
 
 To measure the amount of "soda ash", Na 2 C0 3 , necessary for the 
 precipitation of the sulphates of magnesium, calcium, and iron or per- 
 manent hardness, read carefully paragraph IV on page 87 of Part II. 
 
 The reactions involved may be represented as follows: 
 
 CaS0 4 + Na,C0 3 CaC0 3 + Na 2 S0 4 
 MgS0 4 + Na 2 "CO s = MgC0 3 + Na 2 S0 4 
 
 The amount of "soda ash" used up in this reaction is directly the 
 measure of this substance to be used in treating the water. Thus : If 
 200 c.c. of water were taken, then 5 times the number of c.c. of N / 10 
 Na 2 C0 3 X 0.0053 would represent the weight in grams per liter of 
 Na 2 C0 3 required. This multiplied by 1000 = milligrams per liter and 
 this multiplied by 0.0583 would give the grains per gallon required 
 directly in terms of "soda ash". Multiplying this by 1/7 would give the 
 number of pounds needed per thousand gallons. Where magnesium 
 salts are present as part of the permanent hardness, the MgC0 3 formed 
 as indicated above is to be precipitated as Mg(OH) 2 , the same as under 
 temporary hardness. Hence, all magnesium compounds call for an 
 equivalent of Ca(OH) 2 in addition to the primary reagent needed. This, 
 however, is provided for in the method of analysis which determines 
 all of the magnesium, whatever the form in which it is present; and 
 the secondary reagent, Ca(OH) 2 , for its removal has been considered 
 under the preceding topic; viz., "Treatment with Lime". A double 
 reaction is thus provided for magnesium, whether, the combination be 
 that of a bicarbonate, a sulphate, or a chloride. 
 
 Industrial Methods: While in this discussion the reactions involved 
 in the purification of water have been considered separately and as 
 two distinct processes, in practice they are combined into one opera- 
 tion; that is, the calculated amount of lime for treating, say, 1000 
 gallons of raw water has incorporated with it the amount of soda ash 
 as indicated by the sulphate or permanent hardness per 1000 gallons, 
 and the two reagents thus combined are added directly to the water. 
 
 Very many mechanical devices for automatically measuring the 
 correct amount of each reagent are in use, depending in the main upon 
 
INDUSTRIAL METHODS OF PURIFICATION 17 
 
 the principle that a given weight or volume of the incoming raw water 
 shall operate certain mechanical arrangements, whereby the proper 
 amount of chemical is discharged into the water. The devices are of 
 two general types: the continuous and the intermittent. In the con- 
 tinuous type the raw water flows into the apparatus and is discharged 
 in the purified form ready for use. In the intermittent type the raw 
 water is made to flow through a mechanical measuring arrangement, 
 whereby the chemicals in the proper proportion are added, after which 
 the water is brought into a large settling tank for the time element to 
 enter in for the accomplishing of the reaction involved and also the 
 settling out of the precipitates. Both types are effective, the essential 
 point in any case being that the automatic devices for measuring the 
 reagents be exact and unfailing in their operation. Illustrations are 
 given below of representative devices for each type. They have been 
 selected primarily with reference to their adaptability in the matter of 
 illustrating the principles of water treatment as outlined in the text. 
 
 Arguments are plentiful for the adoption of some form of water 
 purification for practically every sort of industrial use. For domestic 
 and laundry purposes the softening of the water supply by means of 
 the soap employed is, theoretically at least, far more expensive than 
 doing the same work with soda-ash and lime. The various railway sys- 
 tems for the most part make use of purification plants for their service 
 waters. One company with 34 treating plants on its various lines shows 
 a summary for 1915 as follows :* 
 
 Total consumption treated water _ 604,468,087 gallons 
 
 Total scaling material removed by treatment... 1,816,837 pounds 
 
 Saving in fuel, repairs, etc., estimated at 7c 
 
 per pound of incrustants removed $127,171.00 
 
 Cost of treatment, Labor, Chemicals, Mainte- 
 nance, plus 10% on investment 26,017.00 
 
 Total net saving $100,454.00 
 
 Cost of 34 treating plans 70,450.00 
 
 'Communicated by R. C. Bardwell, Chief Chemist, Union Pacific Ry., K. C. 
 
iS 
 
 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 FIG. i EUREKA WATER SOFTENER, CONTINUOUS SYSTEM, AS SUPPLIED BY DODGE 
 
 MANUFACTURING Co., MISHAWAKA, IND. 
 
 The description of the parts can be seen from the explanation accompanying 
 Fig. 2. 
 
INDUSTRIAL METHODS OF PURIFICATION 
 
 FIG. 2 CONTINUOUS WATER PURIFICATION APPARATUS. -DODGE MANUFACTURING Co., 
 
 MISHAWAKA, INDIANA. 
 
 A Wood fiber filter M Reaction chamber 
 
 B' Raw water inlet tank N Spiral accelerator plates 
 
 E Overshot water-wheel P Sludge catchers 
 
 G Soda ash solution tank X Gravity overflow of treated water 
 
 J Lime saturating tank Y Treated water reservoir 
 
 S and P Flushing valves 
 
20 
 
 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 A.. 
 
 FIG. 3 INTERMITTENT PURIFICATION SYSTEM, AS USED BY THE CHICAGO & NORTH- 
 WESTERN RY. Co., DEVISED BY G. M. DAVIDSON, CHEMIST AND 
 ENGINEER OF TESTS, C. & N-W. RY. Co. 
 
 The pump house is located between two tanks. The raw water, together with 
 the chemical mixture, is delivered into the tilting vessel, "P", from which it is 
 discharged to the right or left into the wooden box or trough "r" and "r 1 ". These 
 troughs are provided with shut-off gates, so that the treated water may be delivered 
 entirely into one tank or the other. 
 
MIXING AND MEASURING DEVICES 
 
 21 
 
 FIG. 4 CHEMICAL MIXING AND MEASURING DEVICE. 
 
 The chemical is delivered through the funnel "n", together with the raw water, 
 passing through the pipe "o" into the tilting vessel "P". 
 
 Designed by G. M. Davidson, Chemist and Engineer of Tests, Chicago & 
 Northwestern Ry. Co. 
 
22 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 FIG. 5 CHEMICAL MIXING AND MEASURING DEVICE. 
 
 Showing the measuring pump "k", which it actuated by walking beam attached 
 to shaft "w", discharging the measured quantity of chemicals through the pipe "m" 
 into the tilting vessel "p 2 ". The standpipe "z" is for indicating the depth of the 
 chemical solution remaining in tank "d". 
 
 Devised by G. M. Davidson, Chemist and Engineer of Tests, Chicago & North- 
 western Ry. Co. 
 
RATING OF BOILER WATERS 23 
 
 TABLE IV 
 
 RATING OF BOILER WATERS 
 
 As made use of by the .C. B. & Q. R. R. 
 
 W. H. Wichorst, Engineer of Tests. 
 
 Incrusting Rating. 
 The figures represent parts per 100,000 
 
 1. Very Good Water having sodium carbonate, and hardness less 
 
 than 35. 
 
 2. Good Water having sodium carbonate, and hardness greater 
 
 than 35. 
 
 Water having sulphate hardness less than 5, or total 
 
 hardness less than 20. 
 
 3. Fair Water with sulphate hardness between 5 and 10, and 
 
 total hardness less than 30, or total hardness between 
 20 and 30. 
 
 4. Bad Water with sulphate hardness between 10 and 15, and 
 
 total hardness less than 50, or total hardness between 
 30 and 50. 
 
 5. Very Bad Water with sulphate hardness greater than 15, or total 
 
 hardness greater than 50. 
 
 Foaming Rating. 
 
 A. Very Good Alkali salts less than 7. 
 
 B. Good Alkali salts between 7 and 15. 
 
 C. Fair Alkali salts between 15 and 25. 
 
 D. Bad Alkali salts between 25 and 40. 
 
 E. Very Bad Alkali salts over 40. 
 
 Summary of Ratios: In the preceding discussion the various scal- 
 ing ingredients have all been reduced to the CaC0 3 equivalent, chiefly 
 for convenience in making calculations for the amount of reagent needed 
 in treatment. If, however, we have in hand the analysis of a water 
 giving the hypothetical combination as the various ingredients are sup- 
 posed to occur in the water, it will be found more convenient to make 
 use of a table of factors, as given below. This, in the main, has been 
 compiled from the Report of the Committee on Water Service of the 
 American Railway Engineering and Maintenance of Way Association, 
 embodied in their Bulletin No. 83, January, 1907. See also ''The Hard- 
 
THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 ness of Illinois Municipal Water Supplies," by Dr. Bartow, Proc. Illi- 
 nois Society of Engineers and Surveyors, 1909. 
 
 TABLE V 
 
 SHOWING THE RATIO OF REAGENT TO INCRUSTING MATERIAL REQUIRED FOR WATER 
 
 TREATMENT. 
 
 Wt. of 1 U. S. gallon of water at 65F 58,330 grains 
 
 1 part : 1,000,000 : : x : 58,330 
 Hence, x grains per gallon = 0.05833 X parts per million. 
 
 part free CO 2 requires 1.27 parts CaO 
 
 Na 2 CO 3 
 
 0-53 
 
 CaCOa 
 
 " 0.36 
 
 CaSO* 
 
 0.78 
 
 CaCl 2 
 
 0.96 
 
 MgCOa 
 
 1-33 
 
 MgSO* 
 
 0.88 
 
 MgCl 2 
 acid (H S SOO " 
 
 i.n 
 
 0.57 
 
 CaO 
 CaO 
 
 Na 2 CO 3 
 
 CaO 
 
 Na 2 CO s -fo.47 
 pts. CaO 
 
 Na 2 CO 3 -fo.59 
 pts. CaO 
 
 CaO+i.o8 
 pts. Na 2 CO 3 
 
 and leaves no foaming material 
 
 " i part " 
 
 " no " " 
 
 " 1.04 " 
 
 k u IQ5 
 
 " no " 
 
 " 1.18 " " 
 
 " 1.22 " " " 
 
 Standards for indicating Degrees of Hardness: The English, de- 
 grees of hardness on Clark's scale as it is usually called, represent grains 
 per Imperial gallon ; that is, each degree is one part per 70,000. Hence 
 
 70 000 
 1 degree of hardness by the Clark scale would be ' or 1.2 de- 
 
 grees per U. S. gallon. 
 
 It is usual in this country to refer hardness as well as the other 
 values to parts per million, although the French unit is sometimes used, 
 wherein the reference is to parts per 100,000. 
 
 TABLE VI 
 RELATIVE VALUES FOR DEGREES OF HARDNESS 
 
 
 Grains 
 
 Grains 
 
 French 
 
 U. S. 
 
 per 
 U. S. 
 gallon 
 
 per 
 Imperial 
 gallon 
 
 unit 
 or parts 
 per 100,000 
 
 unit or 
 parts per 
 1,000,000 
 
 1 part per 1,000,000 
 
 0.058 
 
 0.07 
 
 0.10 
 
 1.00 
 
 1 degree 
 
 Clark's scale 
 
 1.20 
 
 1.00 
 
 1.43 
 
 14.30 
 
COMPOSITION AND TREATMENT 25 
 
 Limits of Purification: It should be borne in mind that at ordi- 
 nary temperatures the precipitated material is soluble to the extent of 
 3 to 5 grains per gallon. Hence, this represents the approximate limit 
 to which scaling matter can be removed. At higher temperatures the 
 solubility, especially of the magnesium product, is greatly reduced. So 
 that, if it were practicable to raise the temperature of the water for 
 treatment 50 F, the residual scale forming material could be reduced 
 to 1 or 1.5 grains per gallon.* 
 
 Typical Waters and Their Treatment: In the Table below is given 
 the composition of a number of typical waters from municipal supplies 
 in Illinois, together with the calculated amounts of the reagents called 
 for and the cost of the same calculated on the basis of lime at $6.00 per 
 ton and soda ash at $6.00 per 100 pounds.** 
 
 *"Water Softening", W. A. Powers, Chief Chemist, Santa Fe Railway. 
 **From Hardness of Municipal Water Supplies. Dr. Bartow, Proc. 111. Soc. 
 Engineers and Surveyors 1909. 
 
26 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 8 
 
 Q 
 W 
 
 = 
 
 s 
 
 'in 
 
 :! l 
 
 OOOt Jad 
 
 JSOf) 
 
 -ixojddv 
 
 QOt^ rjt Tf! C5 
 
 < IM CN <N O (M O5 rH 1C MJ 1-1 
 
 ' O CO O5 O <M 
 
 
 3 s 
 
 ^ rJ 
 
 fa "-5 
 
 o - 1 
 
 r, fa 
 
 Is 
 
 o w 
 
 ffl ^ 
 
 H ^ 
 O 
 
 p & 
 
 PH tf 
 < t) 
 W^ 
 
 W 
 
 co o co 01 QO ooeo oo o>oococc-^<-w<TfO'g<cor^iOBO t- oo -H 'o<Ncoo-*j<coeooco 
 t- CN co o> rf -<*- 10 en cMO\co<ri-3irHa>0:>cooi^"<*< N i as icNr-icocNTriococo-* 
 
 fe 
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 -1 CO rH CO T< O O Tf< CO t OO CO CO rH O 1C r* 00 CJ CO ! 
 ') t-^. CO CO OO CO lOCOCOOCSOO-^CO! 
 
 !M Tt< CC QO CO CO rH t> CO rH IN 
 
 O 
 
 lCrH 
 
 & SS ggS&SSSg&i 1 
 
 u 
 
 
 
 
 CO Tfi ;0 
 
 t^ eo ; CD ' i> oo io T* a> --H I to CT> I-H CM ; 
 
 i-lOlrHlc-c-iOOOlMCN :-*01C4rH: 
 
 CN . rH IrHrHCN CN I-H 
 
 io ' to 10 ; 
 
 OlrHTjt, 
 
 CO iC O ; i M< 
 
 lO O CN ^f CO ^, -^ OOO 
 
 
 Tt-oOOO OT^OOTti-* CO iCrHTj _ CftCNCJOOOOiti 
 
 siiss^^s;is i i^^sssiisii^ 
 
 
 I-H * m IN o T< 
 
 3 
 
 s 
 
 ^~ 
 
 o 
 
 
 
 o ; 
 
 O ; rH O O iCO 
 
 i S8 
 
 000 
 
 O ; ; o ; co 
 
 ^J* ' 1C ' CN 
 
 CN : ! : r-t 
 
 rH OX) lCTf<0 
 
 rH t- 10 
 
 ' CO '; i ' CO 
 
 il^QOCOC^OOC 1C 'MO SO rHGCGOOCN ^COr-COt^-OC^-OiCO rH T*4COCOOOOt > -t-tOlOCDOOO 
 
 rH ic t^ in cs co icc^ rH ^-^.of-oooosjccoicat^.-io >c SScN.5aibtraS.<N.co ; 5< 
 
 O'VCOCOCOCM CN OtO OO r-CO^IMt^CNCNOCNCNCNCOl^-V Oi CNr-ir*TfCOCOCOI^COO^r-H 
 
 PQ 
 
 Sss 
 oj <* < 
 
 
 os cues 
 
 : a ; j=' 8 i9 '. 5-1 i 
 ^ S .5P o " '"'"-' : i-' S _ 
 
 *-^ w S * 
 
 s n tf iJ ^ 
 
 
 
 
 i 
 OOOQ 
 
 
CHAPTER II 
 
 FUEL 
 
 Introduction: Motion, industrially considered, is a commodity 
 which, when available in proper form and in sufficient quantity, is des- 
 ignated as power. 
 
 The sources of motion are two in number : 
 
 (1) Gravity 
 
 (2) Chemical Action. 
 
 Gravity is transformed into motion through the medium of falling 
 water, and to a smaller extent by means of wind currents. 
 
 Chemical activity may be derived from the world's fuel supply in 
 greater amount and at less cost than from any other source. 
 
 By the burning of fuel, chemical action may be made to transfer 
 its motion through the medium of steam or, to a smaller extent, as in 
 the internal combustion engine, directly and without any medium, to 
 the working parts of machinery. Proximity to fuel beds, therefore, or 
 accessibility by reason of shipping facilities is an index of present or 
 potential activity along industrial lines. Hence, it is evident that the 
 fundamental purpose of the industrial examination of fuels is to cor- 
 rectly measure the amount of chemically active material which resides 
 in a given sample. This may be determined in two ways: First, by 
 analytical methods wherein the amount of inorganic or chemically in- 
 active substance is determined, as distinct from the organic or chemi- 
 cally active material; and, second, by actual combustion whereby the 
 fuel is made to indicate its activity by the evolution of heat, the quantity 
 of which may be measured. 
 
 Types of Fuel: For convenience in discussion, fuels are divided 
 into solid, liquid, and gaseous types. This classification with further 
 subdivisions may be shown in tabulated form as follows: 
 
 fWood 
 Solid -I Coke and Charcoal 
 
 FUELS 4 
 
 Liquid 
 
 [Coal 
 
 [Alcohol 
 j Distillates 
 [Petroleum 
 
 fNatural Gas 
 Gaseous J House Gas 
 
 [Producer Gas 
 
 Wood: By reason of the high cost of wood it is rapidly passing 
 out of the list of available fuels. While its content of inactive substance 
 in the form of ash is low, its content of free moisture is high, even in 
 
 27 
 
28 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 seasoned wood, and together with combined water constitutes more than 
 half of the wood by weight. Its activity, therefore, measured as heat 
 is only about half that of good coal averaging 6,000 or 7,000 British 
 thermal units per pound. Since a cord of hard wood weighs approxi- 
 mately 4,000 pounds, that amount is about equal in heat value to a ton 
 of coal. 
 
 Coke: Coke is at present chiefly a fuel having special properties 
 which make it suitable for metallurgical purposes. It has very little 
 inactive material except the ash, which is always of higher percentage 
 than in the coal from which it is made. Measured in terms of heat 
 units, coke is equal to the average anthracite coal. 
 
 Coal: Coal is by far the most abundant and cheapest of all fuels. 
 It varies in character from the hard, rock-like anthracites to the soft 
 lignites. The inert non-active substances in the form of water and ash 
 vary from 8 per cent to 40 per cent, and are inversely related to the 
 quantity of heat available. Since these factors are fundamental in the 
 commercial estimation of values, classification, etc., of coal, they will be 
 discussed under the more general treatment of coal which is taken up 
 later. 
 
 Alcohol: Alcohol is a prospective rather than a present source of 
 fuel energy. It has no ash but a large percentage (34.8% of combined 
 oxygen, which approximately represents the inert material. Its heat 
 value in pure form is 12,391 B.t.u. per pound. It is denatured usually 
 by adding about one-third of one per cent of kerosene to render it un- 
 palatable and approximately ten per cent of methyl or wood alcohol to 
 make it poisonous and not easily purified by redistilling. About ten 
 per cent of water is usually added for use in gas engines. Other per- 
 missible formulas are given in United States Department of Agricul- 
 ture, Bureau of Chemistry Bulletin No. 130. 
 
 Distillates: The petroleum distillates are hydro-carbon compounds 
 and are almost entirely free from inactive material. Their heat value 
 varies with the specific gravity, which directly is a measure of the ratio 
 of carbon to hydrogen. The lighter the distillate the higher the ratio 
 of hydrogen and, consequently, the higher the heat value, which may 
 vary from 19,000 to 22,000 B.t.u. per pound. 
 
 Petroleum: Chemically considered, petroleum is substantially the 
 same as distillates but, being heavier, has a lower heat value, ranging 
 from 18,000 to 20,000 B.t.u. per pound. Crude petroleum varies in 
 character, some districts yielding heavier and some lighter oils. Petro- 
 leum residues have had the lighter oils removed by distillation. These 
 residues are of higher specific gravity and lower heat value. 
 
 Gases: Gases are more or less mixed with inert material and, when 
 measured with reference to their chemical activity in the form of heat, 
 
FUEL RESOURCES 
 
 29 
 
 the values are referred to a cubic foot at 60 F. temperature and a 
 pressure of 30 inches of mercury, as representing the average or stand- 
 ard temperature and pressure of the atmosphere. Because of the inev- 
 itable tendency for all forms of this material to have an admixture of in- 
 ert gases, the heat values are very variable. Their character may, how- 
 ever, be expressed in a general way as follows : 
 
 Natural Gas is usually composed in large part of methane or marsh 
 gas, which in pure form has a value of 1010 B.t.u. per cubic foot at the 
 above temperature and pressure. 
 
 House Gas in the majority of cities in the United States is required 
 to have a heat value not less than 600 B.t.u. per cu. ft. 
 
 Producer Gas may vary from 350 to 400 units in the richer form 
 to 125 units as in the "suction" gas producer, and to as low as 90 units 
 per cubic foot in the gases from the blast furnace, which may be looked 
 upon as a special type of gas producer. 
 
 o 
 
 o 
 o 
 
 CM 
 I 
 (0 
 
 I 
 
 L. 
 
 O 
 
 o 
 
 1 
 
 1880 1885 1890 1895 1900 1905 1910 1915 1920 
 
 600 i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i i M 600 
 
 500 
 
 200 
 
 100 
 
 100 
 
 1380 1885 1890 1895 1900 1905 1910 1915 1920 
 
 ANNUAL PRODUCTION OF COAL 
 IN THE UNITED STATES, 1880 TO 1914 
 
 COAL 
 
 Introduction: Of all the fuel supplies available, coal constitutes 
 by far the largest part. Our chief consideration, therefore, will be 
 given to that topic. The annual output of coal in the United States 
 for the year 1914 was 422,329,000 tons. A chart of the production by 
 years is of interest as furnishing an index of industrial activity. A 
 suggestion also is furnished as to the possibility of ultimate exhaustion 
 
THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 of this source of fuel supply, and the necessity of developing the highest 
 possible efficiencies in its use. 
 
 Classification: The classification of coal in common use was out- 
 lined by Frazer* in 1877 and was based on his study of the coals of 
 Pennsylvania. A wider knowledge of the character of western and mid- 
 continental deposits calls for the addition of a few subdivisions. In 
 tabular form the following classification based on that of Frazer most 
 nearly approaches everyday usage: 
 
 [ Anthracites, Volatile matter, below 5% 
 
 Semi-anthracites, 
 
 Semi-bituminous, 
 (Pocahontas) 
 
 COALS ! 
 
 Bituminous, 
 
 Black Lignites, 
 or sub-Bituminous 
 
 Vol., 510% 
 Vol., 1522% 
 
 Eastern, Vol., 2535% 
 
 Vein Moist., 24% 
 
 Mid-Continental, 
 
 Vol., 3545% 
 Vein Moist., 617% 
 
 Vol., 3545% 
 Vein Moist., 1720% 
 
 Vol., 2545% 
 
 Brown Lignites, Vein Moist., 20 25% 
 
 Numerous systems of classification have been proposed, but none 
 has been received with sufficient unanimity to warrant its general adop- 
 tion. In the main, they are based on certain ratios which have come 
 to be designated by technical terms as follows : 
 
 Fuel Ratio: A term originaly proposed by Frazer is represented 
 
 by the fixed carbon divided by the volatile matter: ' Since 
 
 Vol. M. 
 
 this ratio is highest in the anthracites and semi-anthracites, and lowest 
 in the lignites, it serves in a general way as an indication of the type 
 of coal as well as its behavior under conditions of combustion. 
 
 Carbon-Hydrogen Ratio: This term was proposed by Campbell* 
 and represents the percentage of total carbon, divided by the percent- 
 
 T C 
 age of total hydrogen, -g- These factors are obtained by ultimate 
 
 *Trans. Am. Inst. Min. Eng. 6, p. 430. (1877-8.) 
 **U. S. Geo. Survey Professional Paper No. 48, Pt. I, p. 168. 
 
COAL ANALYSIS 31 
 
 analysis and are not usually available. Unfortunately also the hydro- 
 gen factor used by Campbell was the total hydrogen of the coal and 
 also of the free moisture which may have happened to be present at the 
 time of analysis. As this constituent is variable and does not govern 
 either the geological or chemical characteristics of the coal it should not 
 be a contributing element in the carbon-hydrogen ratio. 
 
 The Carbon Ratio* represents the volatile carbon, (that is, the 
 carbon joined with hydrogen or other elements to admit of its assuming 
 a volatile form) divided by the total carbon content of the coal and 
 this multiplied by 100 gives directly the percent the volatile carbon is 
 of the total carbon. The advantage of this ratio is the fact that it 
 remains the same whether the moisture and ash are present or absent, 
 thus eliminating some of the most serious variables inherent in many 
 of the proposed schemes of classification.** 
 
 ANALYSIS OP COAL 
 
 Methods: Coal may be subjected to either the ultimate or proxi- 
 mate method of analysis. In the former, beside the moisture, ash, and 
 sulphur factors, a determination is made of the constituent elements 
 comprising the organic substance of the coal-; namely, carbon, hydro- 
 gen, nitrogen, and oxygen. 
 
 In the proximate method, besides the moisture, ash, and sulphur, 
 there are determined, instead of the elemental substances of the organic 
 part, only volatile matter and fixed carbon. The ultimate analysis 
 furnishes data from which the heat value of the coal can be calculated. 
 The proximate analysis gives the necessary data for judging of the 
 kind and general character of the coal. It is the proximate method 
 only which will be here considered, the main object being to discuss 
 the significance of the various factors, methods of calculation, etc. The 
 
 *Parr, S. W., The classification of coals : J. A. C. S., Vol. 28, 1906, p. 1425. 
 **A brief bibliography of discussions upon coal classification is given as 
 follows : 
 
 Johnson, W. R., Report to United States Government on "American 
 
 Coals," 1844. 
 Ure's Dictionary, 1845. 
 
 Frazer, Persifer, Jr., Trans. Min. Eng., Vol. 6, 1878, p. 430. 
 Watt's Dictionary of Chemistry, Vol. i, p. 1032. 
 
 Rogers, H. D., Report to English Government, Vol. 2, Pt. 2, p. 983. 
 U. S. G. S. Professional Paper No. 48. 
 Parr, S. W., Jour. Am. Chem. Soc., Vol. 28, p. 1425. 
 Campbell, M. R., A. I. M. E., Vol. 36, p. 324- 
 Grout, F. F., Economic Geology, 1907, p. 226. 
 White, David, U. S. G. S. Bulletin No. 382. 
 
32 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC 
 
 analytical methods are taken up elsewhere under the directions for the 
 laboratory processes. 
 
 SAMPLING 
 
 Introduction: Samples may be taken by different methods and 
 for a variety of purposes. Three kinds are generally recognized: 
 1 Hand Samples 
 2 Face Samples 
 3 Commercial Samples 
 
 Hand Samples: As the name implies, hand samples are taken in 
 small amounts and the entire sample is submitted for inspection and 
 analysis. In the nature of the case such samples are selected and are 
 not representative of the mass from which they come. Their analysis 
 may be of interest to the person collecting them but the results are 
 utterly without commercial value or significance. 
 
 Face Samples: This term is applied to samples taken at the work- 
 ing face of a coal seam. They are essential for purposes of scientific 
 study and serve as a basis for determining the changes that occur in 
 the process of mining, transportation and storage. The taking of such 
 samples is not different in principle from the taking of commercial 
 samples. The chief essential is a kit of the knock-down type, not too 
 heavy for packing and not too tedious in setting up and operating. 
 Specific details are not given here.* 
 
 Commercial Samples: The majority of samples are taekn in con- 
 nection with industrial operations, in the process of coal inspection, 
 control of contracts, determination of efficiencies, etc., and involves the 
 sampling of wagon loads, car lots, barge shipments and masses in stor- 
 age. The general principles under any of these conditions are the same. 
 The important features to be observed are given special emphasis as 
 follows : 
 
 COMMERCIAL SAMPLING** 
 
 Necessity of Care: Without question, the critical point in the en- 
 tire range of coal inspection and analysis is in the sampling. If the 
 sample taken is truly representative of the entire lot, the results, if 
 accurate in themselves, furnish correct information as to the larger 
 mass of which the sample is a part. If, on the other hand, the sample 
 is in error, the results of the analysis though correct in themselves will 
 be in error so far as they relate to the mass under consideration. 
 Throughout the process of sampling two points must be observed with 
 scrupulous care : 
 
 *See Bulletin No. 29, 111. State Geol. Surv., p. 17. 
 
 **Adapted from 111. State Geol. Surv. Bulletin No. 29. Purchase and Sale of 
 Illinois Coal on Specification. By S. W. Parr. (1914.) 
 
SAMPLING OF COAL 33 
 
 First The sample taken must be representative of the whole, that 
 is, the distribution of the various substances which go to make up the 
 original mass must be maintained without any change in the relative 
 amount of * the various constituents. 
 
 Second The moisture content, which changes readily, must be 
 under exact control so that at any stage the ratio of moisture present 
 to the original moisture of the mass may be definitely known. 
 
 Material to Be Taken: As stated above, the first essential in a 
 sample is that it shall truly represent the mass of which it is a part. 
 To secure this result a few fundamental conditions must be observed, 
 as follows: 
 
 The gross sample must be representative of the various kinds of 
 material present. That is to say, a mass of coal consists of fine stuff, 
 lump, bone, slate, pyrites, and other constituents. As a rule the "fines" 
 differ in composition from the lump, hence the sample must have these 
 two sorts of material in their proper proportion. The same is even 
 more true of slate or pyrites, of which the composition differs so widely 
 from that of the major part of the mass. An undue amount of such 
 material would cause a serious disturbance in the accuracy of the 
 sample. . 
 
 Amount: In procuring a representative sample a large element 
 of safety resides in the quantity taken. In general, the larger the 
 amount, the more representative it will be. However, conditions differ. 
 It is easier, for example, to procure an even sample from the face of a 
 working vein or from a carload of screenings than from a carload or 
 other mass of lump or run-of-mine coal. In the latter case larger 
 amounts should be taken than in the former. 
 
 The limits of practicability for the proper handling of the sample 
 must however be considered. In general, the gross sample should 
 weigh ^approximately from 200 to 600 pounds. Doubtless 200 pounds 
 of screenings, taken with fairly good distribution throughout the un- 
 loading of a 40- or 50-ton car, will yield a very true sample. The diffi- 
 culties increase greatly with the increase of the size of the particles, 
 as in the case of lump or mine-run coal. If mechanical appliances for 
 grinding are available, the larger amount should be taken, but a smaller 
 sample well crushed down before quartering is better than a greater 
 mass quartered down while the particles are still in larger pieces. 
 
 Ratio of Size to Mass: Assuming that the sample as taken is made 
 up of the various kinds of material in proper 'proportion, the next im- 
 portant item is to maintain these variables in their ratios throughout 
 the process of reducing the gross amount to a small working or labora- 
 tory sample. To insure this result, there must be maintained a certain 
 ratio of size of the particles to size or weight of the mass. This, as a 
 
34 
 
 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 rule, is based on a formula which provides that the weight of the largest 
 piece of impurity shall have a ratio to the weight of the mass of about 
 2: 10,000. For example, a mass weighing 10,000 grams, or about 22 
 pounds, should contain no particles weighing more than 2 grams. This 
 would mean that the largest particle, as for example, a piece of iron 
 pyrites, must not be over 1/4 inch in its greatest diameter. 
 
 The final ratio of sizes, however, should be determined by the meth- 
 ods available for grinding. With mechanical appliances for obtaining 
 the smaller sizes, a table of ratios with greater safety limits can be 
 adopted than is perhaps practicable where the crushing is done by hand. 
 If a power crusher is available, the entire sample should be passed 
 through the mill and reduced to a size which will pass a ^-ineh screen. 
 If the crushing must be done by hand, the first reduction in size of the 
 particles should be such that the entire mass will pass through a 1-inch 
 screen. When by quartering, the sample is reduced to 100 pounds, the 
 size of the particles should be further reduced to a size that will pass a 
 i/2-inch screen, and with a 50-pound sample in hand the crushing should 
 be carried to y^-ineh mesh. The subdivisions with their respective sizes 
 are shown in tabular form as follows: 
 
 TABLE VIII 
 SIZE OF MESH FOR DIFFERENT SUBDIVISIONS OF SAMPLE 
 
 Weight of subdivisions of sample 
 (pounds) 
 
 Size of mesh to which each subdivision 
 should be broken (inches) 
 
 500 
 
 250 
 
 125 
 
 60 
 
 30 
 
 Illinois coals are easily crushed in mills which are available at little 
 expense. Hence it is entirely reasonable to require that gross samples, 
 when reduced in mass to 50 or 75 pounds, shall be passed through a mill 
 set for grinding to approximately 1/8 inch. For this work, a mill which 
 is not of the jaw-crusher or roller type is preferred, since these types 
 produce too large a percentage of fine material, and the harder pieces of 
 slate, especially those of flaky or plate-like structure, are liable to pass 
 in pieces having inadmissably large dimensions in two directions, even 
 though the adjustment used would seem to be fine enough to prevent the 
 passage of such material. A grinder of the coffee-mill type or one with 
 projecting teeth on the grinding surfaces will be found to produce a 
 more uniform size and the minimum amount of dust. The grinding 
 surfaces of such a machine are shown in figure 6, and the same type of 
 mill is shown set up in figure 7. 
 
METHODS OF GRINDING 
 
 35 
 
 Figure 6 GRINDING SURFACES OF COAL CRUSHER 
 
 Figure / COAL GRINDER OF THE COFFEE-MILL TYPE 
 
 Weight about 16 pounds. Readily knocked down for packing. Especially Designed 
 for use in taking Face Samples. 
 
 Mixing and Subdividing: As a further precaution in maintaining a 
 correct distribution of the various constituents, emphasis is placed upon 
 
36 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 the necessity of thorough mixing, followed by even selection of the re- 
 maining sub-divisions. It is true that fine grinding contributes mate- 
 rially to this end but further care is necessary. It is entirely practicable 
 to mix a 50-pound sample, ground as above described, by rolling in an 
 oilcloth about five feet square. This is accomplished by taking one corner 
 of the cloth and carrying it over the pile towards the diagonally oppo- 
 site corner so as to cause the mass to roll over upon itself, then reversing 
 the motion and repeating the process with the other two corners. Fif- 
 teen or twenty such alterations, depending somewhat upon the size of the 
 sample, should be sufficient to effect an even mixture. Where available, 
 however, especially in commercial sampling, a mixer is to be preferred. 
 Such a device is most conveniently made in the form of a drum having 
 cone-shaped ends capable of being closed air-tight, and mounted so as to 
 revolve endwise. 
 
 The subdividing of the larger sample, to reduce it to a convenient 
 size for transmission to the laboratory, requires special consideration as 
 having an important bearing on the maintenance of the correct ratio of 
 constituents. This may be best shown by the data given in Table IX. 
 
 TABLE IX 
 ASH VARIATIONS IN DIFFERENT SIZES OBTAINED FROM DUPLICATE 3-PouND SAMPLES 
 
 Series 
 
 Mesh 
 
 Dupli- 
 cate 
 halves 
 
 Per cent 
 of each 
 size 
 
 CO 2 in 
 "dry 
 coal" 
 
 Ash cor- 
 rected for 
 CO 2 in "dry 
 coal 
 
 a and b compos- 
 ited by calcula- 
 tion 
 
 ii 
 
 On 20 
 
 a 
 b 
 
 41.7 
 48.4 
 
 .40 
 37 
 
 14.11 
 14.00 
 
 
 I 2 
 
 Through 20 
 On 60 
 
 a 
 b 
 
 41.7 
 37-9 
 
 .85 
 
 1. 00 
 
 iS-55 
 15.42 
 
 a 16.32 
 
 
 
 
 
 
 
 b 15.86 
 
 I 3 
 
 Through 60 
 
 a 
 
 16.6 
 
 1.31 
 
 23-89 
 
 
 
 
 b 
 
 13-7 
 
 1.38 
 
 23-65 
 
 Average 16.09 
 
 
 
 
 
 
 
 
 2i 
 
 On 20 
 
 a 
 b 
 
 29.1 
 25.0 
 
 53 
 .46 
 
 I5-9I 
 15-68 
 
 
 2_> 
 
 Through 20 
 On 60 
 
 a 
 b 
 
 48.4 
 51-9 
 
 94 
 .98 
 
 16.23 
 1 6.06 
 
 a 17.90 
 
 
 
 
 
 
 
 b 17.80 
 
 2 3 
 
 Through 60 
 
 a 
 b 
 
 22.5 
 23.1 
 
 1.32 
 1.28 
 
 24.09 
 23.98 
 
 Average 17.85 
 
THE RIFFLE 
 
 37 
 
 Note in this table that series 1 and 2 are 3-pound samples taken by 
 subdividing in the same manner the same gross sample of about 30 
 pounds. Each sample was ground to 8-mesh and sized. It will be seen 
 that in series 1, duplicates a and b had 16.6 and 13.7 per cent of the 60- 
 mesh size, whereas in series 2 the duplicates a and b had 22.5 and 23.1 
 per cent respectively. Note further the great increase in ash in the fine 
 size as compared with the ash in the coarse material. For example, 
 series 1 having an average of 14 per cent of ash in the coarse size has 
 an average of 23.75 per cent in the fine portion. A similar increase in 
 ash is seen in the corresponding sizes in series 2. The ultimate ash 
 average for series 1 is 16.09 per cent and for series 2 it is 17.85 per cent. 
 
 Figure 8 RIFFLE 
 
 These values vary consistently with the variation in the percentages of 
 fine material in the respective series. On the other hand, the duplicate 
 halves a and b throughout, because of their uniformity resulting from 
 the sizing process, show results in the several pairs which check very 
 closely. 
 
 The values as presented in the table, therefore, show clearly that 
 in the process of subdividing the gross sample and in the further reduc- 
 tion of the sample as received at the laboratory, great care must be exer- 
 
38 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 cised to see that no part of the manipulation is of such a nature as will 
 promote segregation of the constituents. 
 
 A riffle constructed according to the pattern shown in figure 8 may be 
 used to advantage after the sample has been reduced by quartering to 
 about 30 pounds. At this stage the sample is ground to 1/8-inch size, 
 hence the riffle openings may be 1/2-inch in width. With this variation 
 in the openings the riffle as shown in fiure 8 is substantially the one de- 
 scribed in the Bulletin of the Ohio Geological Survey, No. 9, p. 313, 1908. 
 
 Moisture Control: The second essential in taking and preparing a 
 sample relates to the free moisture present, and requires that the changes 
 in moisture content ' ' must be under exact control so that at any stage the 
 ratio of the moisture present to the original moisture of the mass may be 
 definitely known.'' 
 
 Loss of Moisture : In coals of this region especially, where the mois- 
 ture in the coal as it comes from the mine averages from 10 to 15 per cent 
 the tendency toward moisture changes is very marked. For example, the 
 process of crushing down the larger sizes affords an opportunity for the 
 escape of moisture. Again, if the coal is spread out on the floor of a hot 
 boiler room or left exposed to currents of air for any length of time there 
 will be a serious change in the moisture factor. Another practice some- 
 times followed is that of assembling the various increments of the gross 
 sample in a sack or other receptacle permitting a relatively free trans- 
 mission of air. Samples kept in this manner for any length of time or 
 shipped in such containers will have a moisture content quite different 
 from the original. 
 
 Precautionary Measures: The methods employed, therefore, in col- 
 lecting and reducing a gross sample must have special reference to this 
 tendency on the part of the free moisture to escape. The work should be 
 done rapidly in a room at or below the normal temperature and, so far as 
 possible^ with the use of closed apparatus which admits of the least pos- 
 sible exchange of the contained air. Precautionary measures of this sort 
 should be made at the very outset. The gross sample, which is made up 
 of small increments collected usually over a considerable length of time, 
 should be enclosed in a tight box or clean garbage can having a tightly 
 fitting cover which can be closed and locked against the possibility of 
 change until the time for grinding and reducing. 
 
 Sampling a Car Load : A car of coal may be sampled to the best ad- 
 vantage in the process of unloading. An occasional half shovelful should 
 be thrown into a proper receptacle so that by the time the car is unloaded 
 approximately 200 pounds, evenly distributed throughout the load will 
 have been taken. This will mean about one-half shovelful for every 
 ten full scoops. They are best taken in the process of shoveling from 
 the bottom of the car, since the top coal rolls down and mixes fairly 
 
COMPOSITE SAMPLES 39 
 
 evenly with the bottom. It should be kept in mind that in taking a 
 sample there must be obtained the different sizes of coal, fine and coarse 
 in their proper proportions from the entire cross-section of the mass, and 
 also an even distribution of the sample lengthwise of the car. Even 
 greater care must be taken to guard against loss of moisture in the pro- 
 cess of collecting and in reducing the gross sample for the reason that as 
 a rule the relative humidity outside of the mine is lower and the ten- 
 dency of the moisture to leave the coal is correspondingly increased. 
 
 Sampling the Car Without Unloading: It has been shown in Table 
 IX, that the finer particles of a coal mass are higher in ash and hence 
 have a greater specific gravity. They are therefore more likely to sep- 
 arate by gravity from the coarser material. On this account, if a car is 
 to be sampled without unloading, it is necessary to dig well toward the 
 bottom in order to obtain a representative sample. Three trenches should 
 be dug crosswise of the load, one near each end and one near the middle 
 of the car. These trenches should go down nearly to the bottom of the 
 mass and each size be taken as nearly as possible in its proper propor- 
 tion. Lump and run-of-mine lots are much more difficult to sample 
 than screenings, but it should be noted that screenings may vary greatly, 
 for not infrequently a car is partially loaded from one bin and finished 
 from another which may be of a different size and composition. After 
 obtaining the gross sample, the methods to be followed are the same as 
 those already given. 
 
 Composite Samples: It is often desirable to composite a number 
 of samples. In this way a single sample may be made to represent a 
 much larger quantity of coal and thus cut down the time and expense 
 involved in procuring the analytical data. In this procedure, however, 
 it must be remembered that even greater care should be exercised in tak- 
 ing the several component samples. The amount of each sample enter- 
 ing into the composite must be in proportion to the mass which it repre- 
 sents, and finally a thorough and positive mixing of the composited mass 
 must be effected before riffiing down the same to the usual 5-pound 
 quantity. 
 
 It is convenient to determine the amount of each sample to be taken 
 by employing an aliquot system of weights. For illustration : Suppose 
 we adopt 1 gram to the 100 pounds as the unit which shall enter into 
 the composite. Then a 100,000-pound car of coal should be represented 
 by 1,000 grams. In compositing, therefore, the entire content of each 
 can will not be taken, but instead an aliquot proportion which will give 
 to each car lot its due amount. It is preferable to use such a factor as 
 shall utilize the major part of the several 5-pound samples. In this way 
 the gross composite from 10 cars would aggregate 20 or 30 pounds in 
 weight. It should be put into the mixer and revolved until a thoroughly 
 
40 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 homogeneous mass is obtained and then riffled down to a 5-pound sam- 
 ple as already described. For this procedure it is obvious that the nec- 
 essary data should accompany the various samples. A ticket inserted in 
 the can before sealing should give the data needed. 
 
 Mechanical Sampling: Numerous attempts have been made to de- 
 
 Fig. 9. Sample Grinder. Sturtevant Mill Company, Boston, Mass. 
 
 vise a mechanical method for taking samples. While it is possible, by 
 such means to eliminate the personal equation, it is difficult to avoid seg- 
 regation or an uneven distribution of coarse and fine material. In the 
 sample grinder illustrated in Fig. 9, there is an evident advantage that 
 
SAMPLE GRINDER 41 
 
 with a power grinder larger samples may be handled, thus dividing 
 rather than multiplying the errors. Fig. 10 shows the method of open- 
 ing up and cleaning the grinder at the end of the operation. Both the 
 central grinding cone and the wing stirrer underneath may be lifted out 
 for cleaning the entire grinding and distributing chamber. The samp- 
 ling feature is so arranged that an aliquot part, approximately 10 per 
 
 Fig. 10. Grinder Opened for Cleaning 
 
 cent, is delivered into the small receptacle in the process of grinding the 
 original mass. In use of such a sample grinder, the facility with which 
 the material may be passed through makes it possible to take much 
 larger initial samples. For example, if occasional shovelfuls are taken, 
 well distributed throughout the unloading of a car in such an amount as 
 to yield say 40 pounds in the aliquot portion, then it is known that ap- 
 
42 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 proximately a 400-pound gross sample has been passed through the 
 grinder. 
 
 Accuracy of the Device: Doubtless the best method for determin- 
 ing the accuracy of the sample delivered by the apparatus is to compare 
 the ash values, water free basis, as obtained from the small sample with 
 the ash value from the main portion, sampled by carefully quartering 
 down by hand in the usual manner. A number of tests of this sort are 
 shown in the Table No. X. 
 
 TABLE X 
 
 ACCURACY OF SAMPLE GRINDER 
 
 Comparison of A$h Values. Dry Basis 
 
 Samples A and B obtained from Main Portion by Quartering and Riffling. 
 
 
 
 Ash in 
 
 A 
 
 B 
 
 Labora- 
 
 
 small 
 
 Ash in main , 
 
 Ash in main 
 
 
 Coal 
 
 sample as 
 
 portion 
 
 portion. 
 
 Number 
 
 
 delivered 
 by grinder 
 
 sampled by 
 quartering 
 
 Duplicate of 
 A : Opposite 
 
 
 
 
 and riffling 
 
 quarter 
 
 8661 
 
 Vermilion Co. 
 
 15-53 
 
 15.22 
 
 15.72 
 
 
 Screenings 
 
 
 
 
 8664 
 
 Vermilion Co. 
 
 14.52 
 
 14.52 
 
 14.65 
 
 
 Screenings 
 
 
 
 
 
 8667 
 
 Vermilion Co. 
 
 19.19 
 
 19.88 
 
 19.72 
 
 
 Screenings 
 
 
 
 
 8670 
 
 Vermilion Co. 
 
 1743 
 
 17.78 
 
 I/.58 
 
 
 Screenings 
 
 
 
 
 Another test has been applied as follows : The samples as obtained 
 in the process of grinding 10 gross samples were delivered into a com- 
 mon receptacle in their proper proportions for compositing. Without 
 further mixing, the mass of approximately 40 pounds was poured into 
 the grinder. The accuracy of the small sample thus obtained was de- 
 termined as before, by comparison of ash, values. The main portion was 
 sampled again by pouring through the mill a second time for a duplicate 
 aliquot delivery. The results are shown in Table No. XI. In both of 
 these tables the agreement between the sample delivered by the mill and 
 the sample obtained from the main portion is very satisfactory, especially 
 when we consider the variations inherent in the processes of analysis for 
 high ash coals. 
 
TESTING OF SAMPLING METHODS 
 
 43 
 
 TABLE XI 
 
 ACCURACY OF SAMPLE GRINDER 
 
 By Comparison of Ash Values. Dry Basis 
 
 DUPLICATE SAMPLE OBTAINED BY SECOND PASSAGE OF MAIN PORTION THROUGH MILL 
 
 Laboratory 
 Number 
 
 Coal 
 (Screenings) 
 
 A 
 
 First aliquot 
 of 10 per 
 cent as 
 delivered 
 
 B 
 Second aliquot 
 of main 
 portion 
 
 8668 
 
 Moultrie County 
 
 19.61 
 
 19.60 
 
 8934 
 
 
 
 20.32 
 
 20.38 
 
 8961 
 
 
 
 20.94 
 
 21.13 
 
 8973 
 
 
 
 19.21 
 
 19.82 
 
 9011 
 
 
 
 19.21 
 
 19.17 
 
 9013 
 
 u 
 
 19.62 
 
 19.41 
 
 9025 
 
 Montgomery " 
 
 13.69 
 
 13-44 
 
 9H3 
 
 Moultrie 
 
 19.64 
 
 19.67 
 
 9U7 
 
 
 
 19-83 
 
 20.03 
 
 9162 
 
 11 U 
 
 20.14 
 
 20.26 
 
 9160 
 
 Montgomery " 
 
 14.17 
 
 13-89 
 
 9180 
 
 Moultrie 
 
 19.32 
 
 18.94 
 
 9185 
 
 Montgomery " 
 
 13-30 
 
 13.48 
 
 91-95 
 
 Moultrie 
 
 . 19.72 
 
 19.90 
 
 91.97 
 
 
 
 18.61 
 
 19.18 
 
 9240 
 
 Montgomery " 
 
 13.20 
 
 12.95 
 
 9242 
 
 Moultrie 
 
 19.82 
 
 19.89 
 
 9244 
 
 it 
 
 18.93 
 
 18.96 
 
 9268 
 
 Montgomery " 
 
 13.48 
 
 13-43 
 
 MOISTURE 
 
 Moisture Conditions and Nomenclature: The topic of moisture 
 control has already been discussed, emphasis having been laid upon the 
 fact that at any stage of the processes the exact ratio of the moisture 
 present to the moisture of the original mass must be definitely, known. 
 This implies that moisture changes do occur. Indeed three moisture 
 conditions exist and, since under each condition all of the accompanying 
 factors are modified to meet the specific change in moisture, a special des- 
 ignation is applied to the coal for each one of these conditions. 
 
 Coal with all of the normal moisture present is designated as "wet" 
 coal or coal ' * as received. ' ' It relates to the moisture at the time of tak- 
 ing the sample. All of the detail of the processes for collecting and re- 
 
44 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 ducing the gross sample up to and including the item of sealing and 
 shipping the 5-pound sample involve the preservation of this initial 
 moisture without loss. 
 
 The second moisture status is that wherein the "wet" or "as- 
 received" coal has been dried to a point of substantial equilibrium with 
 the moisture of the air, so that in an atmosphere of average humidity it 
 would take on or lose additional moisture very slowly or not at all. In 
 this condition the coal sample is said to be "air dry." This is the con- 
 dition to which the chemist must bring the sample in order that the 
 processes of finer grinding and weighing may be carried on without 
 change in the moisture factor. Obviously the amount of moisture lost 
 in passing from the "wet" or "as-received" condition to the "air-dry" 
 condition must be carefully measured. The factor thus determined is 
 designated as the ' ' loss on air drying. ' ' By use of it all of the values ob- 
 tained from analysis of the coal in the * ' air-dry ' ' state may be calculated 
 to the "wet" or "as-received" condition. 
 
 The third condition recognized is that of "dry" coal. This is some- 
 times designated as the "oven-dry" or "moisture-free" state. All of 
 the values found for the coal in the "air-dry" condition may be trans- 
 ferred by calculation and made to apply to the coal as ' i oven-dry. ' ' The 
 necessary factor in this case is the loss of moisture obtained from drying 
 the "air-dry" sample at or slightly above steam temperature, as 220F. 
 for one hour. It is not intended here to give directions for carrying out 
 these processes. The terms employed, however, are of so frequent oc- 
 currence, and in many cases enter so vitally into a correct understand- 
 ing of the methods upon which certain values are based in the making 
 of estimates and arriving at fuel settlements that at least a brief refer- 
 ence seems desirable. 
 
 Carelessness in the use of these terms leads to much confusion. The 
 chemist and the engineer are not always in agreement as to their mean- 
 ing. The results as obtained by chemical analysis upon the air dry sam- 
 ple are of little use to the engineer, whose basis of reference is to the ' ' as- 
 received" or to the "dry" basis. For the purpose of the engineer it is 
 necessary, therefore, to calculate the results which are obtained on the 
 air dry sample back to the "wet" coal and also to the "dry" basis. 
 
 Calculations: To calculate the percentage values obtained on "air- 
 dry ' 7 coal to the ' ' dry-coal ' ' basis, divide each constituent by ( 1 iv ) in 
 which w is the moisture present in the "air-dry" sample. The moisture 
 factor for the "dry" coal is omitted of course, and the sum of the result- 
 ing constituents should total 100 per cent. 
 
 To calculate from the "air-dry" values to the "wet," or "as-re- 
 ceived," condition multiply each percentage for the "air-dry" state by 
 (1 )i n which I is the loss on air drying. The moisture factor thus 
 
INTERPRETATION OF RESULTS 
 
 45 
 
 derived plus the loss on air drying equals the total moisture in the ' ' wet ' ' 
 coal. This and the other factors calculated as described should equal 
 100 per cent. 
 
 INTERPRETATION AND USE OP ANALYTICAL RESULTS 
 
 General Plan: The general purpose involved in making a chemical 
 analysis of coal is to furnish a basis for estimating values. In its sim- 
 plest form it consists in separating the inorganic or non combustible 
 from the organic or heat-producing material. The following outline 
 may serve as an illustration : 
 
 Coal 
 
 Inorganic 
 
 or 
 Non-combustible 
 
 Organic 
 
 or 
 Combustible 
 
 Moisture 
 
 Plant Ash 
 
 Clayey Matter 
 
 Calcium Sulphate 
 
 Calcium Carbonate 
 
 Salt 
 
 Iron Pyrites 
 
 f Complex 
 j Hydrocarbon 
 I Compounds 
 
 Water 
 
 Ash 
 
 I Combustible 
 
 It will be seen from the diagram that the constituents of funda- 
 mental importance are in reality only three in number : Water, ash, and 
 combustible matter. The meaning and use of these values especially in 
 some sort of their modified or corrected forms may be made of great 
 service in connection with the purchase and sale of coal on specification. 
 
 The Interpretation of Moisture Values: The significance of the 
 factor for moisture is important. In coals with high moisture in the 
 vein, a large shrinkage in weight occurs in the process of shipment. In 
 the majority of cases, settlement is made upon the basis of the mine 
 weights. This loss of moisture, therefore, falls ultimately upon the 
 consumer. 
 
 There is a certain agreement also between combined oxygen or the 
 water of constitution and the content of free moisture in the vein sam- 
 ple ; the higher the moisture, the more combined oxygen and the smaller 
 the percentage of combustible in the volatile matter. For this reason 
 there are more heat units per pound of combustible (ash and moisture 
 free) in Pocahontas coal, with 2 per cent of vein moisture, than per 
 pound of combustible (ash and moisture free) in Illinois coal, with 12 
 
46 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 per cent of moisture in the vein sample. The vein moisture, therefore, 
 becomes to a very considerable extent an index of the type or composi- 
 tion of the organic part of the coal. These variations in property will 
 be discussed somewhat further under the topic of Unit Coal. 
 
 Ash. Ash is the inorganic constituent of the coal aside from water. 
 As commonly defined, it is the residue left after burning and is made 
 up of complex substances such as sand, shale or kaolin, gypsum, calcium 
 carbonate, iron pyrites, etc. But, from the list it is evident that there is 
 much opportunity for loss of constituents such as combined water and 
 C0 2 in the process of burning, which, if not corrected for, come to be 
 reckoned as part of the combustible matter. There have come into use, 
 therefore, in connection with the ash determination two terms expressive 
 of this material; namely, "ash as weighed" or simply "ash," and "cor- 
 rected ash." 
 
 The use of a corrected ash factor is primarily of interest in the ac- 
 curate determination of the amount of active or organic matter pres- 
 ent. Thus, unless the line of demarcation between the organic and in- 
 organic substance is properly and precisely drawn, we do not have a cor- 
 rect unit for the true combustible material. This point will be better un- 
 derstood from the discussion of the next topic, Unit Coal. 
 
 Unit Coal : In fuel literature three terms have come into use : 
 
 1. Combustible. 
 
 2. Ash and Water Free Substance. 
 
 3. Pure Coal. 
 
 These terms are synonymous and are intended to represent the active or 
 actual coal substance. The heat value, for example, when referred to 
 the combustible matter, is found by dividing the heat value as obtained 
 on the west coal by 1 (sum of moisture and ash as weighed). From 
 the discussion in the previous paragraph it is evident that there will be 
 a very considerable error unless we make use of a corrected ash, hence 
 there has been suggested* another term, that of Unit Coal, which is in- 
 tended to stand for the pure or actual coal substance as derived from 
 taking into consideration the corrected ash. In other words the attempt 
 is made to differentiate between the non-coal substance and the coal it- 
 self. The latter is a fairly constant material in its heat producing prop- 
 erty and general make-up of its chemical compounds. The non-coal sub- 
 stance on the contrary is made up of a number of ingredients, more or 
 less adventitious, and varying both in actual amount present and also 
 in composition as they pass through the processes of analytical determi- 
 nation. For example the iron pyrites which is a large factor in the non- 
 coal material is weighed out with the coal in the form of FeS 2 . After 
 
 "Illinois Eng. Exp. Sta. Bulletin No. 37. 
 
UNIT COAL 47 
 
 burning to ash it becomes Fe,0 3 and the application of a correction fac- 
 tor to the ash as weighed is necessary if we wish to revert to the original 
 condition of the ash. Similarly, the shale or clayey constituents have in 
 chemical combination, a certain amount of water which is not driven off 
 by drying at steam temperature, but is delivered at a red heat in the 
 process of ashing. Here again, if we wish to obtain a factor for the true 
 ash or non-coal substance we must apply another correction to account 
 for this loss of combined water. An expression, therefore, for the non- 
 coal substance has been adopted as follows: 
 
 Non-coal - = Moisture + Ash-as-weighed + *>/8 S + .08 (Ash-as- 
 w.-ijrhed -- 10/8 S). 
 
 The factors in this expression are derived as follows : In the ash as 
 weighed the FeS 2 of the original coal has burned to Fe._,0 3 . In this com- 
 bination the atomic ratio of the oxygen to the total sulphur which it re- 
 places in the original FeS 2 (that 'is, 2 (FeS 2 ) ) is 48 : 128 or 3 : 8, That is 
 to say oxygen has combined with the iron to the extent of 3/8 of the 
 original sulphur. Hence the ash as weighed may be corrected or brought 
 to its original form so far as the FeS 2 is concerned by adding 5/8 of the 
 weight of the sulphur present in the coal. 
 
 Again the ratio of iron to sulphur in iron pyrites (FeS 2 ) is 56 : 64; 
 that is, the amount of iron present is 7/8 of the weight of the sulphur. 
 The combined iron and oxygen, therefore, weighed as Fe 2 3 are equiva- 
 lent to 7/8 -f- 3/8 or 10/8 of the sulphur present. Hence the expression 
 (Ash-as-weighed - - 10/8 S) represents the ash with the pyritic iron or 
 the resulting oxide Fe 2 : > removed. Therefore, since the original FeS 2 
 from which it comes has no combined water, it is subtracted before ap- 
 plying the correction constant of 0.08. This 8 per cent is a constant and 
 represents the water of hydration for the clayey constituents which we 
 wisli to restore to the ash as in its original form. 
 
 The above formula for "non-coal" becomes therefore the expres- 
 sion for the true coal or 1 1 Unit Coal ' ' in percentage values as follows : 
 
 Unit Coal = 100 - (Water -f Ash-as-weighed + 5/8 S -f 
 .08 (Ash-as.- weighed 10/8 S). 
 
 By clearing of fractions and bringing to its simplest form, this ex- 
 pression becomes : 
 
 Unit Coal == 100 -- (W + 1.08 A -f 21/40 S) in which W is the 
 percentage of water, A is the percentage of ash-as-weighed, and S is the 
 sulphur content. In this expression the factor 21/40 S can not be 
 further simplified by making it 1/2 S, for the reason that our correction 
 for sulphur is already too small by that part of the organic sulphur not 
 covered by the addition to the ash value of 3/8 of the total sulphur in- 
 dicated in the original formula. On the contrary, we shall be approach- 
 ing nearer the truth by increasing slightly the sulphur correction, which 
 
48 THE CHEMICAL EXAMINATION OF WATER, FUEL. ETC. 
 
 may be done with convenience in calculating, by making this factor 
 read 22/40 S or 1/2 S + 1/20 S. 
 
 Sulphur: This constituent of the ash is made a matter of separate 
 determination. The question might be raised as to whether the sulphur 
 should not be grouped with the true coal substance since it contributes 
 somewhat to the heat values in the burning process. But it is distinctly 
 a mineral substance, varies widely in amount and affects the properties 
 of the coal far more specifically through the ash than in its contribution 
 to the heat volume, which is relatively small in amount. Moreover, by 
 segregating it from the heat producing constituents and taking away 
 the heat also which may be credited to it a far more consistent value 
 remains as the true heat to be credited to the Unit Coal substance. This 
 procedure will be found to have very great practical value as well as be- 
 ing of great advantage in the comparative study of coals for classifica- 
 tion and similar purposes. Since the sulphur of coal occurs chiefly as 
 iron pyrites, FeS 2 , it is generally believed that a high sulphur factor 
 represents a high iron factor and, consequently, a tendency for the coal 
 to clinker in burning. This does not necessarily always follow, but it 
 is true in the main. The average content of sulphur in Illinois coals is 
 from 3 to. 4 per cent, with an occasional output as high as six or even 
 seven per cent. In the southern and southeastern field, however, as in 
 Franklin, Williamson, Saline and Jackson Counties, the sulphur con- 
 tent will average from 1 to 2 per cent. 
 
 Volatile Matter and Fixed Carbon: The organic matter of coal 
 when heated above 500 or 600 degrees decomposes giving off combusti- 
 ble gases and, if the temperature is continued to a bright red heat, there 
 remains, in addition to the ash, the fixed carbon or coking constituent 
 of the coal. The volatile matter is of significance largely by reason of 
 the fact that this part of the combustible substance has a tendency to 
 escape into the flue spaces before complete combustion has been effected. 
 With mechanical stokers and modern equipment, this would not occur 
 and, consequently, the matter of high or low volatile matter is of less sig- 
 nificance than formerly. In domestic appliances, however, this is not 
 the case, and larger losses occur in the process of combustion! For such 
 uses, therefore, higher efficiency will be obtained from coals with less 
 volatile matter and a higher percentage of fixed carbon. 
 
 Fixed Carbon: The fixed carbon represents the amount of com- 
 bustible matter which remains behind for complete combustion in the 
 fire box. Its value, therefore, depends upon the form of appliance in 
 which the coal is burned. The fixed carbon plus the ash represents ap- 
 proximately the coke content that might be expected from the original 
 coal. 
 
CALORIMETRY 49 
 
 CALORIMETRIC MEASUREMENTS 
 
 Definitions: Heat values are expressed in two ways, as Calories 
 and as British thermal units. Only the large Calorie is made use of in 
 fuel reference and it represents the amount of heat necessary to raise 
 1 kilo of water through 1C. The full expression is, therefore, Calories 
 per kilo or kilo-Calories. 
 
 The British thermal unit represents the amount of heat necessary 
 to raise 1 pound of water through 1F. The full expression, therefore, 
 would be B.t.u. per pound. 
 
 Since the Centigrade degree is 9/5 or 1.8 times as great as the Fah- 
 renheit degree, and the kilo is 2.2046 times the pound, it follows that one 
 Calorie would be the equivalent in Fahrenheit degrees of 1.8 X 2.2046 
 or 3.968 B.t.u. However, the comparison between units as thus devel- 
 oped is not a comparison between values as made use of in the case of 
 fuels for the reason that the arbitrary amount of coal to which reference 
 is made in both cases is an amount of coal equal to the unit of water de- 
 veloped, that is a kilo of coal to a kilo of water, a pound of coal to the 
 pound of water. For this reason, therefore, the rise in temperature 
 in each case is the same. That is, a pound of coal will raise the temper- 
 ature of a pound of water through as many degrees as a kilo of coal will 
 raise a kilo of water, or a ton of coal a ton of water, etc. The difference 
 in heat values as expressed by these two methods, therefore, is simply 
 the difference in the thermometric readings. A reading taken by the 
 Fahrenheit scale will be 9/5 or 1.8 times as great as the reading taken 
 by the Centrigrade scale. Therefore, to change fuel values expressed 
 in Calories per kilto to B.t.u. per pound, multiply by 1.8. 
 
 Heat Values by Calculation: Heat values may be determined from 
 the ultimate anaylsis by Dulong's formula, which assumes that the heat 
 comes from the combustion of carbon, hydrogen, and sulphur. The us- 
 ual values for these constituents are 
 
 Carbon = 8,080 Cal. or 14,544 B. t. u. 
 
 Hydrogen = 34,500 Cal. or 62,100 B. t. u. 
 
 Sulphur = 2,500 Cal. or 4,500 B. t. u. 
 
 Expressed in the latter set of values, therefore, Dulong's formula be- 
 comes 
 
 14,544 C + 62,100 (H - ?) + 4,500 S = B.t.u. 
 
 8 
 
 In this formula the expression (H ) represents what is termed 
 
 8 
 
 The available hydrogen ; that is, the amount left after subtracting the 
 equivalent hydrogen needed to unite with the oxygen present to form 
 water, 2:16 or 1/8 0. 
 
50 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 Presumably such calculated values would be in close agreement 
 with indicated values by means of a carefully operated instrument. This 
 is true for certain regions, but not for others. The divergence is more 
 pronounced in coals of this region than in the coals of the Eastern United 
 States. "In view of the possible presence of calcium carbonate and the 
 consequent error in the ash determination for many Illinois coals, it is 
 evident that a direct variable in such cases enters into the value for oxy- 
 gen and consequently for the available hydrogen, which would thereby 
 result in a discrepancy as between the indicated and the calculated ca- 
 lorific values. Moreover, a high percentage of oxygen in combination evi- 
 dently may be responsible for variations of quite a different character, 
 as, for example, a different distribution of such oxygen in a manner not 
 
 altogether correctly covered by the expression , or in the ultimate 
 
 8 
 
 form of water. There seems to be, therefore, numerous reasons why 'a 
 calculated calorific value by use of Dulong's formula is of little value 
 for coals of this type. ' '* 
 
 Derivation of Heat Values for Unit Coal: It is obvious that if the 
 heat value of the unit coal is constant within narrow limits for a given 
 mine or region we may if such unit values are known, reverse the cal- 
 culation, making use of any assigned values for moisture, ash and sul- 
 phur, and so determine by calculation the heat value of commercial pro- 
 duct for that particular mine or region for which- the unit coal value is 
 a constant. We shall need to discuss in the first place, therefore, the 
 method of calculating unit coal values. 
 
 From our previous discussion of the formula which has been de- 
 veloped to represent the percentage of unit coal, it is readily seen that 
 the expression for deriving the heat value for that substance would be 
 as follows: Using "W" for water, "A" for Ash, and "S" for sulphur. 
 For coals with values given on the "as-received" or "wet" basis: 
 
 Indicated (Wet) B.t.u. 5,000 S. 
 B.t.u. of Unit Coal 
 
 1.00 (W+1.08A+ 22/408) 
 For coals with values given on the ' ' dry ' ' or moisture free basis : 
 
 Indicated (dry) B.t.u. 5000 S 
 
 B.t.u. of Unit Coal = 
 
 1.00 (1.08A + 22/40 S) 
 
 *Parr, S. W., .111., S. G. S. Yearbook, 1909, p. 236. 
 
 Also, Porter and Ovitz, Bureau of Mines, Bulletin No. i, p. 28-29. 
 
UNIT FUEL- VALUES 51 
 
 The expression 5000 S has been used as indicating the heat due to 
 the combustion of sulphur, for the reason that the value 4500 S as used 
 in Dulong's formula represents the heat of combustion for pure sul- 
 phur, while the heat of combustion of sulphur in the form of pyrites, 
 FeS 2 , combines also the heat of formation of iron oxide, Fe 2 3 . It is 
 the resultant value, therefore, of the several reactions involved that is 
 desired. 
 
 According to the direct tests by Somermeier,* in the combustion of 
 coal with known wights of iron pyrites, the indicated heat per gram of 
 sulphur so combined is 4957 calories. In calculating heat values, the 
 correction introduced for the combinations resulting from calorimeter 
 reactions as compared with open-air combustion is 2042 calories per 
 gram of pyritic sulphur; hence 4957 2042 or 2915 calories (5247 
 B.t.u. ) represents the heat due to burning one gram of sulphur in pyritic 
 form instead of 2250 calories (4050 B.t.u.), the amount which would be 
 credited to sulphur in the free condition. A strict application of these 
 values, therefore, would call for a correction of 5247 S, as representing 
 the heat to be subtracted for the sulphur. This, however, would imply 
 that all of the sulphur is in the pyritic form. Since a certain portion of 
 the sulphur is always present in organic or other form of less heat-pro- 
 ducing capacity, it is deemed more nearly correct to use an even factor 
 of 5000 as representing the heat to be credited to unit amounts of the 
 total sulphur present. 
 
 By computing the heat values as derived by this formula for solid 
 fuels throughout the United States, as published by the United States 
 Geological Survey, the Ohio State Survey, and the Illinois Geological 
 Survey, we have in tabular form, giving the extremes for each general 
 fuel type, the following : 
 
 TABLE XHI 
 
 CLASSIFICATION OF FUEL TYPES BY HEAT VALUES FOR UNIT COAL % OR ACTUAL 
 
 ORGANIC SUBSTANCE 
 
 B.t.u. 
 
 Cellulose and wood 6,500 to 7,800 
 
 Peat :. 7,800 to 11,500 
 
 Lignite, brown 11,500 to 13,000 
 
 Lignite, black, or sub-bituminous coal 13,000 to 14,000 
 
 Bituminous coal (mid-continental field) 14,000 to 15,000 
 
 Bituminous coal (eastern field) 15,000 to 16,000 
 
 Semi-anthracite and semi-bituminous 15,500 to 16,000 
 
 Anthracite 15,000 to 15,500 
 
 '"Jour. Am. Chem. Soc. Vol. 26, p. 566. 
 
52 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 This study has been carried still further by the Illinois State Geological 
 Survey, and the extremes have been derived for the various seams as 
 worked throughout the coal area of the State. 
 
 It is to be recalled that the geologists recognized 16 coal seams for 
 Illinois, counting from the bottom of the coal measures upward. Only 
 seven of these seams are of workable thickness. The numbering follows 
 the geological order, and. not that used in some localities, as at LaSalle, 
 Bloomington, etc., where the number of the seam is that which resulted 
 from the order of their development from the surface downward. 
 
 In table No. XIV a few illustrative examples are given of unit coal 
 values. Complete tables covering all of the producing counties of the 
 state have recently been published* from which these figures have been 
 taken : 
 
 TABLE XIV 
 AVERAGE HEAT VALUE FOR UNIT COAL IN BRITISH THERMAL UNITS PER POUND 
 
 No. 
 
 County 
 
 Coal bed 
 
 Number of sam- 
 ples averaged 
 
 Average B. t. u. 
 "unit coal" 
 
 i 
 
 Sangamon 
 
 c 
 
 T C 
 
 14424 
 
 2 
 
 Sangamon 
 
 6 
 
 C 
 
 14^40 
 
 -2 
 
 Macoupin 
 
 6 
 
 6 
 
 I4^IO 
 
 A 
 
 Madison 
 
 6 
 
 18 
 
 I4^O 
 
 z 
 
 Vermilion 
 
 6 
 
 IQ 
 
 14597 
 
 6 
 
 Vermilion .. ..' . 
 
 7 
 
 Q 
 
 14730 
 
 7 
 
 Williamson 
 
 6 
 
 c 
 
 1 47 So 
 
 
 
 
 
 
 Calculation of Commercial Values: The use which can be made of 
 these "unit" values such as are shown in this table may be readily un- 
 derstood when it is remembered that each number represents material 
 which is 100 per cent pure and that for each per cent of inert matter 
 present, such as water and ash, there is a corresponding decrease in the 
 number of heat units present. That is to say, if a coal has 20 per cent 
 water and ash, then 80 per cent of the "unit" value will represent the 
 heat units present per pound of coal as delivered. Indeed, it is possible 
 by taking account of certain refinements already referred to, such as 
 correction, factors for sulphur and hydration of the shaly constituents, 
 to make a calculation which will be of quite sufficient accuracy for basing 
 bids and entering into contracts involving a guarantee as to heat values. 
 
 "111. State Geol. Survey. Bulletin No. 29. "Purchase and Sale of Illinois Coals 
 on Specification" by S. W. Parr, 1914. 
 
COMMERCIAL ESTIMATES 53 
 
 The method of calculation is exceedingly simple and is based on the fol- 
 lowing expression : 
 
 Let A == weight of ash per pound of coal. 
 
 Let S == weight of sulphur per pound of coal. 
 
 Then 
 
 "Dry" B.t.u. == "Unit" B.t.u. X [1.00 -- (1.08A + 0.55S)] -f 
 5000S. . 
 
 To illustrate, take the "unit" value for coal from Vermilion County, 
 Sample No. 6 in Table XIV. Suppose we wish to know what heat value 
 can be guaranteed on deliveries from a mine of this group on the basis 
 that we can furnish material averaging as the "dry coal," 12 per cent 
 ash, and 3 per cent sulphur, we will have our total non-combustible 
 material corrected by the above formula as follows: 
 
 1.08A 12.96 
 
 0.55S . 1.65 
 
 Total 14.61 
 
 100% - - 14.61% = 85.39% 
 14730 X 85.39% = 12578 
 
 In this calculation the sulphur has been neglected. It has a small 
 heat value equal to 5000 times the weight of sulphur present or 50 times 
 the percentage number, thus: 
 
 50 X 3 = 150 units to be added to the above value, or 
 12578 
 150 
 
 12728 B.t.u. 
 
 Deliveries from this mine, therefore, having ash, and sulphur as 
 indicated above can be depended upon as carrying 12728 heat units per 
 pound of * ' dry ' ' coal, and this factor should be accurate within 100 units 
 in 12000 or less than a variation of 1 per cent from values as they would 
 be determined by direct reading from an instrument. Any other set 
 of values for ash and sulphur would similarly admit of ready calculation 
 and should be used as a basis for calculations involving guarantees of 
 deliveries on a heat-unit basis. If the heat units on the "wet" coal 
 basis are desired assuming, for example, a moisture factor of 15 per cent, 
 the above value as derived for "dry" coal should be multiplied by .85, 
 that is, 12728 B.t.u. X .85 == 10818 B.t.u. per pound of the "wet" coal, 
 assuming a moisture factor of 15 per cent as indicated. 
 
 DIRECT DETERMINATION OF HEAT VALUES 
 
 The Berthier Test: The Berthier test is based on the property of 
 
 carbon to reduce the oxide of lead at a red heat. The higher the percen- 
 
54 
 
 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 tage of combustible present, the larger the button. One gram of coal is 
 mixed with 2 cz. or 60 grams of litharge and heated to redness in a cruci- 
 ble. The weight of the button thus obtained is multiplied by the 421. 
 The product represents theoretically the reducing power of the carbon 
 in terms of British thermal units. It should be increased by about the 
 value of the available hydrogen present. In Illinois coals this does not 
 vary widely from 3.5 per cent, making the addition of a constant neces- 
 sary of about 2000 B.t.u. The results thus obtained may vary from the 
 truth by 300 to 800 units, or from 3 to 8 per cent. The method has his- 
 torical rather than practical interest. 
 
 The Lewis Thompson calorimeter is a bell shaped receptacle for sub- 
 merging water and containing within the bell a cartridge having a mix- 
 ture of coal, 2 grams; with 22 grams of a mixture of potassium nitrate 
 3 parts, and potassium chlorate, 1 part.* Occording to Schorer-Kest- 
 ner** this apparatus normally gives results that are in error by about 15 
 per cent. This apparatus also dates back to a time when a mere approx- 
 
 Fig. ii. Filling an Oxygen Bomb from a High-pressure Cylinder Supply 
 (Courtesy of the Standard Calorimeter Co., East Moline, 111.) 
 
 imation to the correct values was all that seemed to be demanded by fuel 
 users. At the present time a degree of exactness is required which was 
 impossible with either of the methods just described. 
 
 There are two types of calorimeters using oxygen as a medium for 
 carrying on the combustion, those in which the oxygen is maintained 
 
 *For details of the Apparatus see Fuel, Water and Gas Analysis. By Kershaw. 
 **Jour. Soc. Chem. Ind. Vol. /, p. 869. 
 
OXYGEN BOMB CALORIMETERS 
 
 55 
 
 at atmospheric pressure and those using oxygen under approximately 
 25 atmospheres. 
 
 Of the first type, the best known perhaps are Fischer's, Carpen- 
 ter's, W. Thompson's, etc., which conduct a current of oxygen into a 
 chamber containing the fuel. The chief disadvantage results from im- 
 perfect combustion, especially with high ash coals due to fusion of the 
 ash with consequent enclosure and protection of the carbonaceous mat- 
 ter from further oxidation. 
 
 I 
 
 Fig. 12. Oxygen Calorimeter Dismantled 
 
 Oxygen Bomb Calorimeters: Calorimeters using oxygen at ap- 
 proximately 25 atmospheres pressure are designated as of the Berthelot 
 or Mahler type from the names of the investigators who were pioneers 
 in their development and use. A typical bomb of this type is shown 
 in Fig. 11 connected with the high pressure oxygen supply for charg- 
 ing. A carefully weighed amount of coal is held in a capsule within the 
 bomb. The bomb after charging is placed in the can A, Fig. 12, and a 
 
56 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 known quantity of water added. After placing in the insulated recep- 
 tacle B, and putting in place the cover C, an equalization of tempera- 
 tures is brought about by rotation of the stirrer. After ignition and 
 equalization again of the temperature, the factors are at hand for de- 
 riving the heat value of the coal according to the formula : 
 
 rise X total water 
 : Wt. of coal 
 
 For example, if one gram of coal were taken and the total water used, 
 including the water equivalent of the apparatus, were 2400 grams, then 
 for a rise of say, 4 Fah. the heat value would be 9600 B.t.u. By this 
 procedure, therefore, may be found the rise in temperature which a 
 given weight of coal will impart to an equivalent weight of water, thus 
 satisfying the conditions of the definition of the British thermal units 
 per pound of fuel. 
 
 Radiation Corrections: If the system containing the bomb and 
 measured quantity of water is operated at a temperature above or below 
 that of the room a gain or loss of heat will result due to radiation. This 
 may be corrected for in a very accurate manner by taking the thermom- 
 eter readings each minute for a preliminary period of five minutes and 
 also for a final period of five minutes. The rates of radiation change 
 thus obtained are incorporated into a formula covering the period of 
 combustion and equalization of the system. Details of procedure and 
 calculations are given under directions for manipulation (Part II, 
 
 P . in). 
 
 Adiabatic Insulation: To avoid the necessity of accounting for ra- 
 diation losses and eliminating possible errors, as also to simplify the 
 matter of readings and calculations, various methods of insulation in- 
 volving adiabatic conditions have been developed. To be thoroughly ef- 
 fective these methods should involve complete control over the temper- 
 ature of the insulating part of the apparatus in such a way as to cause 
 the temperature to rise coordinately with that of the combustion sys^ 
 tern. Such instruments are designated as adiabatic calorimeters. Their 
 greater convenience of operation and possibilities of extreme accuracy 
 are apparent. 
 
 Acid Values: One other condition exists in the use of the Mahler 
 type of calorimeter which requires consideration. Because of the use 
 of pure oxygen at a high pressure and temperature, certain reactions 
 take place which do not occur in the ordinary process of combustion. 
 For example, a small amount of residual air present upon closing the 
 instrument has free nitrogen which under the conditions of combustion 
 is partially oxidized to N 2 5 or with the moisture present in the bomb 
 it becomes HN0 3 . Similarly the nitrogen of the coal burns to a greater 
 
THE PEROXIDE CALORIMETER 57 
 
 or less extent to HN0 3 . The sulphur in the coal which under ordinary 
 conditions of combustion burns to S0 2 , in the calorimeter burns to SO 3 
 or with the moisture present, to H 2 S0 4 . These two highly corroding 
 acids make it necessary to protect the interior surface of the bomb. This 
 is accomplished by use of an enamel, by a spun lining of gold or plati- 
 num, or by constructing the bomb of an acid resisting alloy equivalent 
 in that respect to gold or platinum. If such a precaution is disregarded, 
 as for example, if the enamel type of protection becomes cracked and 
 scaled off or if a lining of spun metal such as nickel is employed, the 
 solvent property of the acids becomes active. There are two sources of 
 error which result from such conditions, one is the heat of solution re- 
 sulting from the chemical action. This of course should not be credited 
 to the heat content of the coal. The other is the lowering of the amount 
 of free acid which thus escapes measurement and otherwise would be 
 corrected for. In high sulphur coals of the Illinois type the error from 
 this source may be of considerable moment. 
 
 Details of manipulation and procedure for taking account of the 
 various corrections to be applied with the attending methods of calcula- 
 tion are given in connection with the laboratory directions in Part II. 
 
 Peroxide Calorimeter: Another type of calorimeter is extensively 
 used in which the coal is mixed with a chemical which will supply the 
 oxygen to complete the combustion within a closed cartridge. This 
 method is more conveniently available perhaps for technical work. The 
 procedure is described under the directions for calorimetric measure- 
 ments. (Part II, p. 98.) 
 
 The principles involved are as follows: Sodium peroxide, Na 2 O 2 , 
 when mixed with coal in suitable proportion and ignited, may be made 
 to burn or react through an appreciable period of time but, instead of 
 the formation of gaseous products as in the ordinary process of combus- 
 tion, the C0 2 and H 2 unite with the chemical employed to form the 
 carbonate and hydrate of sodium, which are solids. These reactions 
 shown in detail are as follows : 
 
 i 2Nao(X+C=2Na,O+C0 2 
 I 2Na 2 0+ CO 2 =Na,CO 8 +Na 2 
 
 I Na 2 2 +H 2 =Na 2 0+H 2 
 I Na 2 0+H 2 0=2NaOH 
 
 Of the total heat developed in the reactions under -(a), 0.73 repre- 
 sents the heat combination between the carbon and oxygen. Also, under 
 (b), the total heat of the reactions is made up of 73 parts, which includes 
 
 *The complete reactions involved are probably expressed by the equation 
 Ka O -hXa O4-O-f4H=4NaOH. (See "The Constants of the Parr Calorime- 
 ter."" "jour. "of the Am. Chem. Soc., Vol. XIX, p., 1616). 
 
58 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 the heat formed by the union of the hydrogen with the oxygen, and 27 
 parts, which represents the secondary reaction or combination of the 
 water with the chemical. This distribution of heat values is fortunate 
 for the reason that we may make the factor 0.73 a constant which repre- 
 sents the part of the total heat to be taken as the equivalent of the heat 
 of ordinary combustion. Other corrections must be applied to the indi- 
 cated rise in temperature as detailed in the method of operation (Part 
 II, p. 101). A brief discussion having reference to the reason for apply- 
 ing the corrections is here given. 
 
 First. The ignition is effected by an electrically heated fuse wire. 
 The amount of heat introduced by the electric current and combustion 
 of the wire is found to be .005 F. 
 
 Second. The combination of the ash with the sodium peroxide, 
 forming in the main sodium and aluminum silicates, is attended with a 
 slight increment of temperature which is found by direct experiment to 
 amount to 0.005 F for each per cent of ash present in the fuel. 
 
 Third. The sulphur in ordinary combustion burns to sulphur diox- 
 ide, S0 2 , while in the reaction with the chemical the ultimate result is 
 Na 2 S0 4 . The difference in the heat resulting from the two reactions 
 should be subtracted from the indicated temperature. The amount of 
 the correction is determined by burning pure iron pyrites, FeS 2 , in the 
 apparatus and comparing the heat evolved with the accepted heat value 
 for the combustion of an equivalent amount of sulphur to S0 2 *. The 
 difference is found to be equivalent to 0.010 F for each per cent of sul- 
 phur present in the coal. 
 
 Fourth. For the more perfect combustion of all types of coal 
 and also for supplying the seemingly needed free or nascent oxygen for 
 the combustion of the hydrogen, an accelerator is used in conjunction 
 with the sodium peroxide, preferably chlorate of potash, finely pulver- 
 ized and dry. . The heat of decomposition of this material plus the re- 
 combination of the free oxygen with the Na 2 O resulting from the reac- 
 tions with carbon amount to 0.270 F per gram of KC10 3 used. 
 The indicated rise of temperature is, therefore, first corrected for the 
 several components enumerated, and the corrected rise is used in the 
 formula : 
 
 rXwX0.73 
 B.t.u.= c - 
 
 in which "r" is the corrected rise in temperature, "w" is the water 
 equivalent of the water and metal of the apparatus, 2123.3 grams, and 
 "C" is the weight of coal taken, 0.5 gram. This will give us the rise in 
 degrees Fahrenheit or B.t.u. which an equal weight of coal will yield 
 
 *Idem, p. 1620. 
 
DERIVATION OF CONSTANTS 59 
 
 upon combustion, provided the actual heat of combustion is imparted to 
 an equivalent of water. 
 
 Since, in the above formula the factors for "w," "C," and, the con- 
 stant 0.73 occur in all cases, their resulting value becomes a constant 
 equal to 3100. Thus, 
 
 3 =3100. 
 
 COMPOSITION OP ILLINOIS COALS 
 
 A recent survey carried on by the Illinois State Geological Survey 
 in cooperation with the U. S. Bureau of Mines covered all of the coal 
 producing counties of Illinois and included something over 100 mines. 
 The analytical values for the coals from these mines have been averaged 
 for the various counties and are assembled in Table No. XV. Where 
 mining operations are carried on from different seams in the same 
 county, the average for the single seam indicated is given separately 
 and not for the county as a whole. Also, for the reason that some of the 
 seams vary widely in character from north to south, the letters "N" or 
 "S," are occasionally used to designate the general region from which 
 the samples are taken. Similarly, since in some rather restricted locali- 
 ties a marked alteration in the seam occurs from East to West, the let- 
 ters "E," and "W," are used as in Perry County, the letter "E" signi- 
 fies for seam No. 6, East, and "W" west of the DuQuoin anticline. 
 
 Partial bibliography relating to coal calorimetry. 
 
 Lord and Somermeier, Ohio State Geological Survey, fourth series, Bul- 
 
 letin 9, p. 320. 
 
 Atwater, Jour. Am. Chem. Soc., Vol. 25, p. 659. 
 Parr, S. W., Jour. Am. Chem. Soc., Vol. 29, p. 1606. 
 Parr, S. W., Jour. Ind. & Eng'g. Chem., Vol. I, No. 9, p. 673. 
 investigations in the Use of the Bomb Calorimeter. By J. A. Fries. U. S. 
 Dept Ag. Bui. 94. 1907. 
 
 Coal, Its Composition, Analysis, etc. By E. E. Somermeier. 1912. 
 Technical Gas and Fuel Analysis. By A. H. White. 1914. 
 Bureau of Standards Scientific Paper No. 230. By H. C. Dickinson. 
 The Function of Nitrogen in the Bomb Calorimeter. By S. A. Register. 
 Jour. Ind. and Eng. Chem., Vol. 6, p. 812. 
 
 Report of the Committee -4 on Methods of Sampling and Analysis of Coal. 
 Proc. Am. Soc. Testing Mat, Vol. X 14, p. 444; 1914. Also Jour. Ind. and Eng. 
 Chem., Vol. V, p. 517; 1913. 
 
6o 
 
 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 TALBE No. XV. 
 
 AVERAGE ANALYTICAL AND HEAT VALUES FOR PRODUCING COUNTIES IN ILLINOIS. 
 *COMPILED FROM BULLETIN No. 2Q ILL. STATE GEOL. SURVEY. 
 
 Table 
 No. 
 
 County 
 
 Geolog- 
 ical 
 Seam 
 
 Total 
 
 Moisture 
 
 Vol- 
 atile 
 Matter 
 
 Fixed 
 Carbon 
 
 Ash 
 
 Sul- 
 phur 
 
 Carbon 
 Diox- 
 ide 
 
 B.t.u. 
 
 "Unit 
 Coal" 
 
 1 
 
 Bureau 
 
 2 N 
 
 16.27 
 
 38.35 
 
 38.00 
 
 7.38 
 
 2.93 
 
 .89 
 
 10883 
 
 
 
 
 
 Dry 
 
 45.80 
 
 45.39 
 
 8-81 
 
 3.50 
 
 1.40 
 
 12997 
 
 14477 
 
 1 
 
 Christian 
 
 1 C 
 
 11.31 
 
 38.89 
 
 40.94 
 
 8-86 
 
 2.35 
 
 .43 
 
 11602 
 
 
 
 
 
 Dry 
 
 43.85 
 
 46.16 
 
 9.99 
 
 2.65 
 
 .48 
 
 13081 
 
 14717 
 
 3 
 
 Clinton 
 
 6 S 
 
 12.62 
 
 37.08 
 
 40.10 
 
 10.20 
 
 3.90 
 
 .66 
 
 10796 
 
 
 
 
 
 Dry 
 
 42.45 
 
 45-90 
 
 11.67 
 
 4.46 
 
 .75 
 
 12355 
 
 14290 
 
 4 
 
 Franklin 
 
 6.8 
 
 9.04 
 
 34.62 
 
 47.78 
 
 8.56 
 
 1.45 
 
 .44 
 
 11837 
 
 
 
 
 
 Dry 
 
 38-06 
 
 52.53 
 
 9.41 
 
 1.59 
 
 .48 
 
 13013 
 
 14538 
 
 5 
 
 Fulton 
 
 5 N 
 
 16.16 
 
 36-27 
 
 37.09 
 
 10.48 
 
 3.14 
 
 1.33 
 
 10363 
 
 
 
 
 
 Dry 
 
 43.26 
 
 44.24 
 
 12.50 
 
 3.74 
 
 1.59 
 
 12361 
 
 14416 
 
 6 
 
 Gallatin 
 
 5 S 
 
 4.30 
 
 35.93 
 
 49.08 
 
 10.69 
 
 3.79 
 
 .24 
 
 12616 
 
 
 
 
 
 Dry 
 
 37.54 
 
 51.29 
 
 11.17 
 
 3.96 
 
 .25 
 
 13183 
 
 15109 
 
 7 
 
 Gallatin 
 
 6 S 
 
 7.54 
 
 34.96 
 
 45.68 
 
 11.82 
 
 4.34 
 
 .23 
 
 11916 
 
 
 
 
 
 Dry 
 
 37.81 
 
 49.41 
 
 12.78 
 
 4.70 
 
 .25 
 
 12888 
 
 15136 
 
 8 
 
 Jackson 
 
 2 S 
 
 9.28 
 
 33.98 
 
 51-02 
 
 5.72 
 
 1.29 
 
 .29 
 
 12488 
 
 
 
 
 
 Dry 
 
 37.46 
 
 56.24 
 
 6.30 
 
 1.42 
 
 .32 
 
 13765 
 
 14818 
 
 9 
 
 Jackson 
 
 6 S 
 
 8.96 
 
 34.44 
 
 46.40 
 
 10.20 
 
 2.65 
 
 .40 
 
 11609 
 
 
 
 
 
 Dry 
 
 37.83 
 
 50.97 
 
 11.20 
 
 2.91 
 
 .44 
 
 12751 
 
 14608 
 
 10 
 
 La Salle 
 
 2 C 
 
 15.70 
 
 39.54 
 
 36.17 
 
 8.59 
 
 3.48 
 
 96 
 
 10731 
 
 
 
 
 
 Dry 
 
 46.91 
 
 42.89 
 
 10.20 
 
 4.12 
 
 1.15 
 
 12728 
 
 14444 
 
 11 
 
 La Salle 
 
 5 C 
 
 14.76 
 
 41.33 
 
 34.26 
 
 9.65 
 
 3.38 
 
 61 
 
 10692 
 
 
 
 
 
 Dry 
 
 48.49 
 
 40.19 
 
 11.32 
 
 3.97 
 
 .71 
 
 12543 
 
 14397 
 
 12 
 
 La Salle 
 
 7 C 
 
 13.56 
 
 40.87 
 
 37.80 
 
 7.77 
 
 3-68 
 
 .17 
 
 11347 
 
 
 
 
 
 Dry 
 
 47.28 
 
 43.73 
 
 8.99 
 
 4.26 
 
 .20 
 
 13127 
 
 14685 
 
 13 
 
 Logan 
 
 5 C 
 
 14.20 
 
 37.19 
 
 37.44 
 
 11.37 
 
 3.34 
 
 1.42 
 
 10490 
 
 
 
 
 
 Dry 
 
 43-35 
 
 43.40 
 
 13.25 
 
 3.89 
 
 1.66 
 
 12226 
 
 14400 
 
 14 
 
 Macon 
 
 5 C 
 
 14.15 
 
 36.68 
 
 ?8-83 
 
 10.34 
 
 3.57 
 
 .52 
 
 10661 
 
 419 
 
 
 
 
 Dry 
 
 42.73 
 
 45.23 
 
 12.04 
 
 4.16 
 
 .60 
 
 12418 
 
 14 
 
 15 
 
 Macoupin 
 
 6 C 
 
 13.88 
 
 38.20 
 
 37.75 
 
 10.17 
 
 4.31 
 
 .34 
 
 10657 
 
 
 
 
 
 Dry 
 
 44.36 
 
 43-83 
 
 11.81 
 
 5.00 
 
 .39 
 
 12875 
 
 14349 
 
 16 
 
 Madison 
 
 6 S 
 
 13.47 
 
 38-59 
 
 38-03 
 
 9.91 
 
 4.22 
 
 .42 
 
 10760 
 
 
 
 
 
 Dry 
 
 44.60 
 
 43.95 
 
 11.45 
 
 4.88 
 
 .49 
 
 12435 
 
 14370 
 
 17 
 
 Marshall 
 
 2 N 
 
 15.10 
 
 39-06 
 
 38.68 
 
 7.16 
 
 2-79 
 
 .48 
 
 11315 
 
 
 
 
 
 Dry 
 
 46.01 
 
 45-56 
 
 8.43 
 
 3-23 
 
 .56 
 
 13327 
 
 14796 
 
 18 
 
 Marion 
 
 6 8 
 
 10.79 
 
 37.53 
 
 40.46 
 
 11.22 
 
 3.96 
 
 .45 
 
 11069 
 
 
 
 
 
 Dry 
 
 42.07 
 
 45-35 
 
 12.58 
 
 4.44 
 
 . -51 
 
 12408 
 
 14511 
 
 19 
 
 Menard 
 
 5 C 
 
 17.33 
 
 35.88 
 
 38.62 
 
 8.17 
 
 3.44 
 
 .50 
 
 10499 
 
 
 
 
 
 Dry 
 
 43.40 
 
 46.72 
 
 9.88 
 
 4.16 
 
 .60 
 
 12700 
 
 14478 
 
 20 
 
 Mercer 
 
 1 W 
 
 15.58 
 
 39.17 
 
 35-80 
 
 9.45 
 
 4.69 
 
 .53 
 
 10673 
 
 
 
 
 
 Dry 
 
 46.40 
 
 42.41 
 
 11.19 
 
 5.55 
 
 .63 
 
 12643 
 
 14546 
 
 21 
 
 Montgomery 
 
 6 C 
 
 14.15 
 Dry 
 
 36-88 
 42.96 
 
 39.14 
 45.59 
 
 9.83 
 11.45 
 
 3.84 
 4.47 
 
 .70 
 
 .83 
 
 10642 
 12396 
 
 14290 
 
 22 
 
 Moult rie 
 
 6 C 
 
 6-83 
 Dry 
 
 39.15 
 42.02 
 
 42.32 
 45-42 
 
 11.70 
 
 12.56 
 
 4.02 
 4.31 
 
 .57 
 .61 
 
 11877 
 12748 
 
 14882 
 
 23 
 
 Peoria 
 
 5 C 
 
 14.96 
 
 36-65 
 
 36-99 
 
 11.40 
 
 3.26 
 
 1.50 
 
 10506 
 
 
 
 
 
 Dry 
 
 43.10 
 
 43.49 
 
 13-40 
 
 3-83 
 
 1.77 
 
 12354 
 
 14614 
 
 24 
 
 Perry 
 
 6 C 
 
 9.92 
 Dry 
 
 32.72 
 36.81 
 
 46.97 
 52.15 
 
 10.39 
 11.53 
 
 .92 
 1.02 
 
 .25 
 
 .28 
 
 11335 
 12583 
 
 14407 
 
 25 
 
 Perry 
 
 6 W 
 
 11.00 
 
 36.75 
 
 41.97 
 
 10.28 
 
 3.36 
 
 .56 
 
 11087 
 
 
 
 
 
 Dry 
 
 41.29 
 
 47.16 
 
 11.55 
 
 3.78 
 
 .63 
 
 12457 
 
 14359 
 
 26 
 
 Randolph 
 
 6 S 
 
 11.13 
 Dry 
 
 37.28 
 41.95 
 
 40.14 
 45.17 
 
 11.45 
 12.89 
 
 4.24 
 
 4.77 
 
 .58 
 .65 
 
 10855 
 12214 
 
 14351 
 
 27 
 
 Saline 
 
 5 S 
 
 6.92 
 
 35.44 
 
 49.06 
 
 8-58 
 
 3.76 
 
 .39 
 
 12314 
 
 
 
 
 
 Dry 
 
 38.08 
 
 52.70 
 
 9-22 
 
 4.04 
 
 .42 
 
 13229 
 
 14794 
 
 28 
 
 Sangamon 
 
 5 C 
 
 14.35 
 Dry 
 
 37.30 
 43.55 
 
 37-57 
 43-86 
 
 10.78 
 12.59 
 
 4.16 
 
 4.86 
 
 .59 
 .69 
 
 10555 
 12323 
 
 14415 
 
 29 
 
 St. Clair 
 
 6 S 
 
 11.25 
 
 39-57 
 
 38-39 
 
 10.79 
 
 3.99 
 
 .63 
 
 11028 
 
 
 
 
 
 Dry 
 
 44.59 
 
 43.26 
 
 12.15 
 
 4.50 
 
 .71 
 
 12426 
 
 14457 
 
 30 
 
 Tazewell 
 
 5 C 
 
 14.38 
 
 37.74 
 
 38.23 
 
 9.66 
 
 3.10 
 
 1.20 
 
 10809 
 
 
 
 
 
 Dry 
 
 44.08 
 
 44.65 
 
 11.28 
 
 3.62 
 
 1.40 
 
 12624 
 
 14496 
 
 31 
 
 Vermilion 
 
 6 C 
 
 14.45 
 Dry 
 
 35.88 
 41.94 
 
 40-33 
 47.14 
 
 9-34 
 10.92 
 
 2.55 
 2.98 
 
 .75 
 
 .88 
 
 10920 
 12764 
 
 14575 
 
 32 
 
 Vermilion 
 
 7 C 
 
 12.99 
 
 38-28 
 
 38.75 
 
 9.98 
 
 2.93 
 
 .56 
 
 11143 
 
 
 
 
 
 Dry 
 
 44.00 
 
 44.53 
 
 11.47 
 
 3.37 
 
 .64 
 
 12807 
 
 14740 
 
 33 
 
 Williamson 
 
 6 S 
 
 9.31 
 
 33.38 
 
 48.90 
 
 8.41 
 
 1.54 
 
 .36 
 
 11913 
 
 
 
 
 
 Dry 
 
 36.81 
 
 53.92 
 
 9.27 
 
 1.70 
 
 .40 
 
 13136 
 
 14655 
 
COAL CONTRACTS 61 
 
 PURCHASE AND SALE OP COAL UNDER SPECIFIC ATION J 
 
 Present-day tendencies relating to the basis for coal contracts are 
 reflected in the following quotations: 
 
 When a proper sample of the coal is secured, the chemical analyses and calori- 
 meter determinations for B.tu. are a better guide to the value of the coal than 
 are one or two boiler tests for the same purpose. 2 
 
 The purchase of coal under specification is as advantageous as a definite under- 
 standing regarding the quality and other features of any other product, or of a 
 building operation or engineering project. The man who buys under specification 
 gets what he pays for and pays for what he gets. 3 
 
 The heating value expressed in British thermal units per pound is 
 the most direct measure of the value of coal. Contracts made on what 
 is termed the "heat-unit basis" provide therefore that the amount of 
 money paid shall be in direct proportion to the number of heat units 
 delivered. It is evident that the number of heat units varies inversely 
 with the quantity of ash and moisture. That the bidder should be thor- 
 oughly familiar with these factors in their application to the coal which 
 he proposes to furnish is self-evident. A thorough understanding of the 
 methods of awarding contracts is also essential to the dealer who pro- 
 poses to enter bids on a competitive basis. 
 
 Use of a Double Standard of Reference: The cost of a given lot 
 of coal must be based upon the weight of the material. The sample 
 taken should represent the coal "as delivered," and, as already empha- 
 sized, moisture changes in the sample are to be carefully guarded 
 against. Variations in quality are taken into account by varying the 
 price per ton directly in proportion to the number of heat units deliv- 
 ered. In the award of contracts and in computations for payment, 
 therefore, the calculations are based upon the heat units per pound in 
 the coal "as delivered." 
 
 Concerning the ash, if there were no other effect produced by ash 
 variations than a corresponding variation in the heat units then no fur- 
 ther account would be taken of that constituent since it would be taken 
 care of in the calculations involving the heat units. However, on ac- 
 count of the expense in handling, and because of a lowering of efficiency 
 resulting from excessive ash, an additional modification in price is made 
 for this constituent. For greater convenience where comparisons are 
 involved and to eliminate the moisture variable, it is found preferable 
 
 1 Adapted from Illinois State Geological Survey. Bulletin 29. By S. W. Parr, 
 
 1914- 
 
 2 The Purchase of Coal : The Arthur D. Little Inc. Laboratory of Engineer- 
 ing Chemistry, pages 10 and n, 1909. 
 
 3 Pope, G. S., Purchase of coal by the government under specifications : U. S. 
 Geol. Survey Bull. 428, page 10, 1910. 
 
62 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 to refer the ash values to the "dry-coal" basis. This involves the use 
 of a double standard of reference; the heat units are referred to the 
 "wet" or "as-received" basis and the ash is referred to the "dry" or 
 ' * moisture-free ' ' basis. 
 
 The methods of applying the various conditions involved, in the pur- 
 chase of coal by the Illinois State Board of Administration, are given as 
 follows : 
 
 Bids and Awards: (1). Bidders are required to specify their coal 
 offered in terms of British thermal units "as-received," but ash is speci- 
 fied on the "dry-coal" basis. These values become the standards for 
 the coal of the successful bidder. 
 
 (2). In order to compare bids, all proposals are adjusted to a com- 
 mon basis. The method used is to merge all three variables ash, calorific 
 value, and the price bid per ton into one figure. This figure will be 
 the cost in cents of 1,000,000 British thermal units and is derived as 
 follows : 
 
 (a). All bids are adjusted to the same ash percentage by selecting 
 as the standard for comparison the proposal that offers coal containing 
 the highest percentage of ash. Each 1 per cent of ash content below 
 that of this standard will be assumed to have a positive value of 2 cents 
 per ton, and accordingly the price will be decreased 2 cents, which is the 
 amount of premium allowed under the contract for 1 per cent less ash 
 than the standard established in the contract. Fractions of a per cent 
 will be given proportional values. The adjusted bids will be figured to 
 the nearest tenth of a cent. 
 
 (b). On the basis of the adjusted price, allowance will then be 
 made for the varying heat values by computing the cost of 1,000,000 
 British thermal units for each coal offered. This determination will be 
 made by multiplying the guaranteed British thermal units per pound by 
 2,000 and dividing the product by 1,000,000. This factor gives the guar- 
 anteed number of million units per ton of delivered coal. Dividing the 
 adjusted price as found under (a) by this factor gives the cost per 
 million heat units. 
 
 A convenient form for tabulating bids to indicate the various fac- 
 tors entering into the final computation of cost is shown below. 
 
AWARDING OF CONTRACTS 
 
 63 
 
 TABLE XVI 
 CONVENIENT FORM FOR TABULATING BIDS 
 
 No, 
 
 Joal offered 
 
 Guarantees 
 
 Price per ton 2000 Ibs. 
 
 Computed 
 cost in cents 
 per 1,000,000 
 B. t. u. 
 
 If (b) 
 
 Ash in 
 "dry 
 coal" 
 (per- 
 cent) 
 
 B. t. u. 
 "as re- 
 ceived" 
 
 As 
 bid 
 
 As adjust- 
 ed for ash 
 
 IT (a) 
 
 A 
 B 
 C 
 
 Vermilion Co. 
 Screenings 
 
 17 
 '16 
 14 
 
 10300 
 10400 
 12500 
 
 1.50 
 1-35 
 
 2.OO 
 
 1.50 
 1-33 
 1.94 
 
 7-3 
 6.4 
 7.8 
 
 Sangamon Co. 
 Screenings 
 
 Williamson Co. 
 Screenings 
 
 
 Price and Payment: Payment for coal specified in the proposal 
 will be made upon the basis of the price therein named, which has been 
 corrected for variations in heating value and ash from the standard 
 specified in the contract, as follows: 
 
 (a). Considering the guaranteed heat units on the "as-received" 
 basis, the correction in price will be a proportional one and is determined 
 by the following formula : 
 
 B.t.u., delivered 
 B.t.u., guaranteed 
 
 X bid price = price corrected for B.t.u. 
 
 The correction is figured to the nearest tenth of a cent. 
 
 (b). For all coal that by analysis contains less ash on a dry-coal 
 basis than the percentage guaranteed, a premium of 2 cents per ton for 
 each whole per cent less will be paid. An increase in the ash content 
 of 2 per cent above the standard established by the contractor is toler- 
 ated without exacting a penalty. "When this excess is greater than 2 
 per cent, deductions are made in accordance with the following table: 
 
64 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC 
 
 TABLE XVII 
 SHOWING DEDUCTIONS FOR EXCESS ASH* 
 
 Ash as 
 estab- 
 lished 
 in pro- 
 posal 
 
 No 
 
 deduc- 
 tion for 
 limits 
 below 
 
 Cents per ton to be deducted 
 
 Maxi- 
 mum 
 limits 
 for ash 
 
 2 
 
 4 
 
 7 
 
 12 
 
 18 
 
 25 
 
 35 
 
 Percentage of ash in "dry coal" 
 
 Percent 
 5 
 6 
 
 7 
 
 7 
 8 
 
 9 
 
 10 
 
 ii 
 
 12 
 
 13 
 H 
 15 
 
 16 
 
 17 
 18 
 
 iQ 
 
 20 
 
 7-8 
 8-9 
 9-10 
 
 IO-II 
 
 11-12 
 12-13 
 
 13-14 
 14-15 
 15-16 
 I6-I7 
 I7-I8 
 I8-I9 
 19-20 
 20-21 
 
 8-9 
 9-10 
 
 IO-II 
 11-12 
 12-13 
 13-14 
 
 14-15 
 I5-I6 
 I6-I7 
 I7-I8 
 I8-I9 
 19-20 
 20-21 
 21-22 
 
 9-10 
 
 IO-II 
 II 12 
 
 IO-II 
 I.I-I2 
 12-13 
 
 13-14 
 14-15 
 15-16 
 
 17 18 
 
 11-12 
 
 12-13 
 
 13-14 
 
 1 14-15 
 I5-I6 
 I6-I7 
 I7-I8 
 18-19 
 19-20 
 2O-2I 
 21-22 
 22-23 
 
 12-13 
 13-14 
 14-15 
 I5-I6 
 I6-I7 
 I7-I8 
 
 I8-I9 
 I9-2O 
 2O-2I 
 21-22 
 
 13-14 
 14-15 
 15-16 
 
 16-17 
 17-18 
 
 12 
 
 13 
 14 
 14 
 15 
 16 
 
 16 
 17 
 18 
 19 
 19 
 
 20 
 21 
 
 22 
 
 8 
 
 12-13 
 13-14 
 14-15 
 
 m 16 
 
 
 10 
 
 ii 
 
 
 12 
 
 16-17 
 
 17-18 
 18-19 
 
 
 13 
 14 
 
 18-19 
 19-20 
 
 20-21 
 21-22 
 22-23 
 
 
 
 JC 
 
 
 19 20 
 
 16 
 
 20-21 
 21-22 
 22-23 
 
 
 
 17- 
 18 
 
 
 
 
 
 
 
 
 
 
 As an example of the method of determining the deduction in cents 
 per ton of coal containing ash exceeding the standard by more than 2 
 per cent, suppose coal delivered on a contract guaranteeing 10 per cent 
 ash on the "dry-coal" basis shows by analysis between 14.01 and 15 per 
 cent (both inclusive), or, for instance, 14.55 per cent, the deduction ac- 
 cording to the table is 1 cents per ton (reading to the right on line be- 
 ginning with 10 per cent on the extreme left, which in this case is the 
 standard, to the column containing "14.01-15," the deduction at the top 
 of this column is seen to be 7 cents). 
 
 NOTE If the ash standard is an uneven percentage, the table will 
 be revised in order to determine deductions on account of excessive ash. 
 For example, if the ash standard is 6.53 per cent, each percentage value 
 beginning with 6 in the left-hand column and all figures in the line read- 
 ing to the right of 6 will be increased by 0.53. There would be no deduc- 
 
 *Bulletin, 378, United States Geological Survey, Results of Purchasing Coal 
 under Government Specifications. 
 
COMBUSTION OF COAL 65 
 
 tion then in the price of ash in delivered coal up to and including 8.53 
 per cent, whereas for coal having an ash content, for instance, between 
 11.54 and 12.53 per cent the deduction would be 12 cents per ton. 
 
 The Formulation of Proposals: The coal operator should know 
 what guarantees he can maintain in making up his bid. The purchaser 
 should be able to determine the likelihood of the operator being able to 
 fulfill his guarantee without excessive penalties. Where unit coal values 
 are known for a particular mine or district this information is a simple 
 matter of calculation and has already been explained on p. 52. The 
 Table No. XV of average unit values for the producing counties will 
 furnish the initial data. 
 
 THE COMBUSTION OF COAL 
 
 General Principles: The difficulties attending the complete com- 
 bustion of bituminous coal are directly related to the volatile matter 
 present. The showing of large volumes of smoke, therefore, is a sure 
 sign of serious loss of the fuel constituents. The underlying principles 
 furnish a sufficient explanation for the losses which accompany heavy 
 smoke. A brief enumeration, therefore, is here given: 
 
 (a) At temperatures below 750F about one-half of the total vola- 
 tile matter of bituminous coal is discharged. 
 
 (b) The first distillates at these lower temperatures are composed 
 chiefly of the so-called heavy hydrocarbons, ethylene, propylene, ben- 
 zene, etc., including some compounds which are light oils at ordinary 
 temperature. 
 
 (c) Under the most favorable conditions it is difficult to burn these 
 compounds without producing a smoky flame, a prerequisite being a 
 much larger mixture of air than that required for the distillates which 
 come off at the higher temperatures, mainly methane (CH 4 ) and 
 hydrogen. 
 
 (d) A high percentage of moisture, which is also discharged simul- 
 taneously with the heavy hydrocarbons, accentuates the difficulty by 
 sudden expansion into steam and consequent displacement of air, as 
 well as by lowering the temperature of the combustion chamber while 
 the process of vaporization is proceeding. 
 
 From this enumeration, it is evident that to discharge these first dis- 
 tillates into a relatively cooler zone emphasizes the unfavorable condi- 
 tions for combustion and results also in a condensation of some of the 
 compounds, all of which is made evident by the appearance of dense 
 volumes of smoke. This is always the result with house-heating appli- 
 ances and is more or less evident with all steam-generating devices which 
 are fired intermittently. 
 
 The mechanical or physical features essential to smokeless combus- 
 tion are now well understood as the result of the elaborate investigations 
 
66 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 carried on by Mr. W. L. Abbott and Mr. A. Bement at the Chicago Edi- 
 son plant. The two fundamental elements involved are: First, a con- 
 tinuous accession of fuel by some system of automatic stoking; and, sec- 
 ond, the discharge of the volatile products into a highly heated combus- 
 tion zone for accomplishing both the necessary admixture of air and the 
 completion of the oxidation processes. 
 
 STORAGE, WEATHERING, AND SPONTANEOUS COMBUSTION 
 
 Deterioration: Coal is subject to deterioration from the time of 
 breaking out at the mine until used. These losses, however, are rela- 
 tively small. A sudden drop occurs in the first week or two, due no 
 doubt to the liberation of certain of the hydrocarbons. Subsequent 
 losses are more largely due to the absorption of oxygen and the forma- 
 tion of humic compounds which are part of the subsequent coal texture. 
 The cut shown herewith is typical and illustrates the kind and amount 
 of the losses over the space of one year's storage. 
 
 Perhaps even more serious than the loss by weathering is the disin- 
 tegration or slaking which takes place, whereby the coal is reduced in 
 size. It is thus rendered more difficult to maintain a proper circulation 
 of air through the fuel bed. The matter of weathering is discussed in 
 detail in Bulletin No. 38 of the Illinois Engineering Experiment Station. 
 
 Spontaneous Combustion: All coals of the bituminous type are 
 subject to spontaneous combustion. A detailed study of the causes has 
 been made in Bulletin No. 46 of the Illinois Engineering Experiment 
 Station. Briefly summarized, they are as follows : 
 
 1. The oxidation of coal is continuous over a wide range of time 
 and conditions, and begins with the freshly-mined coal at ordinary tem- 
 peratures. A number of oxidation processes are involved which are 
 more or less distinct in character, some being relatively slow and moder- 
 ate in form, while others are rapid and vigorous in their action. 
 
 2. In general, we may say that for a given coal a point exists as 
 indicated by the temperature, below which oxidation is not ultimately 
 destructive and its continuance is dependent upon certain accessory con- 
 ditions which, if withdrawn, the oxidation ceases. On the other hand, 
 above this critical point, which is best indicated by temperatures, oxida- 
 tion is ultimately destructive and is characterized by the fact that it 
 does not depend for its continuance upon external conditions, but is self- 
 propelling or autogenous. 
 
 3. The point of outogenous oxidation, while varying for different 
 conditions, may be indicated by temperatures of the mass ranging from 
 200 to 275 C, depending to a great extent upon the fineness of division. 
 The phenomenon of fire or actual kindling does not occur until a much 
 higher temperature is reached, usually beyond 350 C. 
 
SPONTANEOUS COMBUSTION 67 
 
 4. The temperature at which autogenous oxidation begins is the 
 sum of numerous temperature components, each one of which, either be- 
 cause of its own contribution to the total heat quantity or because of its 
 function as a booster for chemical activities, must be looked upon as a 
 dangerous factor tending directly to the ultimate result of active com- 
 bustion throughout the mass. An enumeration of the more important 
 elements which contribute towards this end are the following: 
 
 a. External Sources of Heat: Oxidation, especially of the lower 
 or moderate form, is greatly accelerated and in certain phases directly 
 dependent upon an increase of temperature. What may be termed ex- 
 ternal or physical sources of heat, and thus presumably avoidable, are 
 suggested by the following: 
 
 (1) Contact of the mass with steam pipes, hot walls or floors un- 
 der which are placed heat conduits of any sort. 
 
 (2) The heat of impact or pressure due to the method of unload- 
 ing or to the depth of piling. 
 
 (3) Climatic or seasonal temperature at the time of storage. 
 
 (4) The direct absorption of heat from the sun or from reflecting 
 surfaces. 
 
 ~b. Fineness of Division: Coal in a fine state of division presents 
 a very much larger surface and brings a much larger quantity of react- 
 ing substances in contact with oxygen than when in solid masses. Un- 
 der these conditions, with a condensation or accumulation of relatively 
 large amounts of oxygen immediately surrounding or in contact with 
 the particles of carbonaceous matter, the circumstances are exceedingly 
 favorable for rapid oxidation upon the arrival of the mass to a suitable 
 temperature. But, more especially does this fineness of division facili- 
 tate the initial form of oxidation described under c below. 
 
 c. Easily Oxidizable Compounds: An initial stage of oxidation 
 exists in bituminous coals which does not result in the formation of 
 carbon oxide. There are present in coals of this type unsaturated com- 
 pounds which have a marked avidity for oxygen at ordinary tempera- 
 tures, the products being humic acid or other fixed constituents of the 
 coal texture. Coals vary widely in this matter and it has been proposed 
 by some to regard this property as an index of the liability to sponta- 
 neous combustion. It is, however, very largely dependent upon the 
 freshness of the coal and upon the fineness of division, (See, under & 
 above), and should be looked upon as a contributing factor, though in 
 coals of the Illinois type at least, with their high per cent of sulphuf , 
 this action should doubtless be considered second in importance to that 
 of iron pyrites. 
 
 d. Iron Pyrites: The presence of sulphur in the form of iron 
 pyrites is a positive source of heat due to the reaction between sulphur 
 and oxygen. Here again rapidity of oxidation is directly dependent 
 
68 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 upon fineness of division. Since coals of the Mid-Continental field espe- 
 cially have a much higher earthy or ash content in the fine material, and 
 since iron pyrites is a large component of this substance, it follows that 
 the presence of dust or duff in all coals of the Illinois type is a positive 
 source of danger. Since coals of the Illinois or Mid-Continental field 
 have in the larger number of cases iron pyrites averaging over 5 per 
 cnt or as sulphur above 2y 2 per cent, the heat increment from the oxida- 
 tion of only 1/5 of this material is sufficient to raise the temperature of 
 the mass approximately 70, assuming that there is no loss by radiation. 
 Under usual conditions, and especially considering the greatly accel- 
 erated rate of chemical activity accompanying a rise of temperature, this 
 oxidation may proceed with such rapidity that the heating up of the 
 mass will be but little affected by the loss of heat due to radiation, ex- 
 cept in relatively shallow piles. Coals of low sulphur content or such as 
 do not have sulphur greatly in excess of, say 1-% per cent are popularly 
 supposed to be immune from heating, but no method of selection or 
 hand-picking at the mine can eliminate all of the iron pyrites. Lumps 
 of coal, to all outward appearance of good texture, may have nodules or 
 detached bands of iron pyrites. These become centers of activity and 
 with the addition of moisture such coal will have many scattered spots 
 where heating begins. If fine coal is mixed in with the coarse, the diffi- 
 culty is accentuated. Doubtless a complete separation of fine and lump 
 material in such cases would lessen the danger. 
 
 e. Moisture: Moisture, while essential to pyritic oxidation, is 
 given separate mention because its importance is apt to be underesti- 
 mated. Any coal with pyritic conditions as above mentioned will be fa- 
 cilitated in that action by moisture. It is to be noted in this connection 
 that the normal water content or vein moisture of coals in this central 
 region is rarely below 10 per cent and ranges usually from 12 per cent 
 to 15 per cent. The presence of such water must be borne in mind in 
 considering the likelihood of chemical activity on the part of the pyrites 
 present. 
 
 /. The Oxidation of Carbon and Hydrogen: A third stage of oxi- 
 dation of the carbonaceous material exists by reason of the property of 
 certain of the hydrocarbon compounds of coal to oxidize with the forma- 
 otni of C0 2 and H 2 at temperatures in excess of 120 to 140. Though 
 this type of oxidation does not take place appreciably at ordinary tem- 
 peratures, it must, be looked upon as an exceedingly dangerous stage in 
 the process of oxidation, owing to the very much higher quantity of heat 
 which is discharged by the oxidation of carbon and hydrogen; so that 
 the temperature of autogenous action, though ordinarily occurring at a 
 higher point by 100 or more, may be quickly attained as a result of this 
 form of oxidation. Any initial heat increments, therefore, which threaten 
 
WEATHERING OF COAL 69 
 
 to bring the chemical activities along to the point where the oxidation 
 processes invade the carbonaceous material in this manner must be 
 looked upon as dangerous. For example, any of the initial or contribu- 
 tory processes which result in raising the temperature of the mass 50 
 
 i J_ 
 
 EXPOSED BINS 
 COVERED BINS- 
 UNDER WATER 
 
 FIG. 13. VERMILION COUNTY, ILLINOIS, SCREENINGS SHOWING THE LOSS IN HEAT 
 
 VALUE FOR THE FIRST TWO WEEKS, AND FOR EACH MONTH 
 
 FOLLOWING THROUGHOUT THE YEAR 
 
 above the ordinary temperature would, in all probability, have enough 
 material of the sort involved in such action to continue the activity until 
 another 50 had been added, which would thereby attain to the condition 
 wherein this third stage of oxidation would begin. 
 
70 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 g. Autogenous Oxidation: The fourth stage of oxidation may be 
 indicated as occurring at temperatures above 200 to 275 and differs 
 from the previous stages in that the action is autogenous and not depend- 
 ent upon other sources of heat to keep up the reacting temperature. Ac- 
 tivity in this stage is further accelerated by the fact that above 300 the 
 decomposition of the coal begins which is exothermic in character, 
 thereby contributing somewhat to a further increase in temperature. 
 The ignition temperature is reached at a point still further along, usually 
 in excess of 300 to 400C. 
 
 Storage Methods: The above formulation of the various stages and 
 types of oxidation clearly indicates the principles which must be ob- 
 served in any attempt at the prevention of spontaneous combustion. The 
 following enumeration, therefore, of preventive or precautionary meas- 
 ures is to be considered as suggestive rather than complete in character : 
 
 First, The avoidance of external sources of heat which may in any 
 way contribute toward increasing the temperature of the mass is a first 
 and prime essential. 
 
 Second, There must be an elimination of coal dust or finely-divided 
 material. This will reduce to a minimum the initial oxidation processes 
 of both the carbonaceous matter and the iron pyrites. These lower forms 
 of oxidation are to be looked upon as boosters, without which it would 
 be impossible for the more active and destructive activities to become 
 operative. 
 
 Third, Dryness in storage and a continuation of the dry state, to- 
 gether with an absence of finely-divided material, would practically 
 eliminate the oxidation of the iron pyrites. The drenching down with 
 water of heating piles, where the sulphur content is high and uniformly 
 distributed, accentuates the difficulty. Where pyritic activity is local- 
 ized in spots or is so small in amount as to reach a possible exhaustion, 
 the drenching with water may check the heating or prolong the action 
 so that oxidation of the carbonaceous matter does not get under way to 
 a serious extent. In such cases, however, there is no ultimate safety ex- 
 cept in the removal of the heated zones. 
 
 Fourth, The submergin of coal, it is very evident, will eliminate 
 all of the elements which contribute towards the initial temperatures. 
 As to its industrial practicability, it can best be determined by actual 
 experience. 
 
 Other processes may be suggested by the formulation of the princi- 
 ples involved. Such, for example, would be the distribution throughout 
 the coal of cooling pipes through which a liquid would circulate having 
 a lower temperature than the mass. This would serve to carry away 
 any accumulation of heat and confine the oxidation to the lower stages 
 only. On the contrary, the proposition sometimes made to provide cir- 
 
RELATIVE GAS VOLUMES 71 
 
 dilating passages for the transmission of air currents is of questionable 
 value, since it may result in the contribution of more heat by the added 
 accessibility of oxygen than will be carried away by the movement of 
 the air. 
 
 CHAPTER III 
 FLUE GAS 
 
 Gas Volumes: Air has the composition by volume of 20.78 per 
 cent of oxygen and 79.22 per cent of nitrogen. In passing through the 
 fuel bed the nitrogen is unchanged, being chemically inactive, and pro- 
 ceeds into the flue spaces in the same form in which it entered the 
 furnace. The oxygen, on the contrary, enters into chemical reaction, 
 combining with the carbon to form CO 2 and CO and with the hydrogen 
 to form H 2 0. As in all chemical processes, an excess of the reagent 
 must be present in order to accomplish a rapid and complete reaction. 
 There will always be found, therefore, in the flue gases a very consider- 
 able amount of excess or unused oxygen. The essential constituents, 
 therefore, to be determined in the analysis of flue gases are 
 
 (1) C0 2 
 
 (2) Oxygen 
 
 (3) CO 
 
 (4) Nitrogen (by diff.) 
 
 In the combustion of carbon, the reaction which occurs may be 
 represented by the formula C -j- O 2 = CO 2 . This means that for each 
 volume of oxygen one volume of CO 2 results. If, therefore, pure carbon 
 were burned and the exact amount of air were supplied to completely 
 represent the volumes indicated in the above equation, the resulting flue 
 gas would be composed of 20.78 per cent of C0 2 and 79.22 per cent of 
 nitrogen. This, therefore, would represent the extreme limit of theo- 
 retical possibility as to the percentage of the volume of CO, in such a 
 flue gas. However, from the principal already stated as to the necessity 
 of an excess of reagent, the rapid and complete oxidation of the carbon 
 can only be effected by having an excess of oxygen, at least 50 per cent 
 more than that utilized in the combustion, and even at this ratio the 
 oxygen would begin to be sufficiently low in amount to result in the 
 formation of a very considerable quantity of CO. From actual experi- 
 ence it would seem that a content of CO 2 in the flue gases of, say, 12 
 per cent approaches the limit of practicability, while doubtless from 8 
 to 10 per cent of CO 2 would represent conditions which are above the 
 average in practice. 
 
 It should be borne in mind also that while carbon constitutes the 
 larger part of the fuel content, the combustion of hydrogen (which on 
 
72 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 the average represents from 3 to 4 per cent of the coal), would be rep- 
 resented by the formula 
 
 2H 2 + O 2 = 2H 2 0. 
 
 That is, one volume of oxygen results in two volumes of water vapor. 
 Now, since in the process of analysis the water vapor condenses and 
 does not appear in the results, it must follow that the nitrogen which 
 accompanied the original oxygen into the furnace in this case is left 
 alone without an accompaniment of gaseous product corresponding to 
 the C0 2 as in the case of the combustion of carbon. To this extent, 
 therefore, the ratio of theoretical C0 2 in the flue gases is diminished. 
 From these considerations it will appear that the uses that may be made 
 of the constituents are : First, a very fair estimate of efficiency of the 
 firing may be obtained from the percentage content of C0 2 in the flue 
 gases. If, for example, it is known that for the boiler setting and equip- 
 ment of a given furnace, it is capable of carrying on combustion to an 
 extent which will be represented by 10 per cent of CO 2 in the flue 
 gases, then when the flue gases show only 5 per cent of this constituent, 
 there is evidence of carelessness in firing which is capable of correction. 
 Calculations: The flue gas constiuents and temperatures afford a 
 basis f 01*, calculating efficiencies and heat losses. Three general features 
 are usually included as follows: 
 
 (a) The number of pounds of air entering per pound of fuel. 
 
 (b) The ratio of air entering the grate to the air used. 
 
 (c) The loss of heat passing up the chimney. 
 
 (a) Pounds of Air Entering per Pound of Coal: The gram 
 molecule of any gas, that is, the molecular weight of the gas in grams, 
 has a definite volume and is the same for all gases; namely, 22.4 liters 
 at standard temperature and pressure. For example 44 grams of C0 2 
 have a volume of 22.4 L. ; 32 grams of O 2 have a volume of 22.4 L., etc. 
 In a mixture of gases, therefore, the weight of each constiuent, W, 
 in 22.4 L. equals the molecular weight X the percentage present thus : 
 (1) W = mol. wt. of component X per cent. 
 
 In arriving at the weight of air entering the grate, the weight of 
 the total nitrogen will give the most direct factor for calculating the 
 air. For example, making use of equation (1) the weight of nitrogen, 
 W 1 , in a gram-molecule-volume would be : 
 W 1 = 28 X per cent N 2 
 
 In order to refer the weight of nitrogen present to a unit quantity 
 of fuel, we shall need to determine, first the amount of pure carbon 
 involved in the production of the unit volume of flue gas. This can be 
 readily accomplished by deriving the weight of carbon in the gas and 
 making one gram of carbon the unit of reference. For example, 12/44 
 of the CO 2 and 12/28 of the CO present is carbon. 
 
CALCULATION OF RATIOS 73 
 
 If we let C represent the weight of carbon in the unit volume, then 
 
 C = 12/44 X 44 CO 2 + 12/28 X 28 CO 
 hence 
 
 C = 12 (C0 2 + C0) 
 
 If, therefore, C represents the number of grams of carbon which 
 deliver a flue gas with W 1 grams of nitrogen, then the weight of nitro- 
 
 W 1 
 
 gen per gram of carbon burned is - or in terms of the assigned 
 
 \s 
 
 values, 
 
 (2) W -_?!!?! or 7N = 
 
 V / - ci / /^i /~\ i /"* /~\ \ 
 
 12 (C0 2 + CO) 3 (C0 2 + CO) 
 
 Assuming for illustration a chimney gas of the following composition : 
 
 C0 2 10. % 
 
 Oo 8. % 
 
 CO" 5% 
 
 N 2 81.5% 
 
 resulting from the combustion of a coal having 70 per cent of carbon 
 exclusive of the carbon lost in the ash. Then by substituting these 
 values in equation (1) we have: 
 
 7 V 1 ^ 
 
 1 
 
 3 X (10 + 5) 
 
 That is, 18.11 grams nitrogen in the flue gases accompany the combus- 
 tion of 1 gram of carbon. Similarly there would be 18.11 pounds of 
 nitrogen in the flue gases from 1 pound of carbon, and for a coal of 
 70% carbon the weight would be .70 X 18.11 = = 12.68 pounds N 2 . Since 
 nitrogen passes through the furnace unchanged the calculation to the 
 equivalent weight of air entering 'is, 
 
 77 : 100 :: 12.68 : x 
 x = 16.47 
 
 Hence the weight of air entering per pound of coal is 16.47 pounds. 
 
 (b) Ratio of Air Entering to Air Used: From the discussion 
 under (a) the weight of oxygen per pound of carbon would be repre- 
 sented by the expression, 
 
 32 O, 8 2 
 
 (3) W 1 = - or 
 
 12 (CO, + CO) 3 (CO 2 + CO) 
 
74 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 Substituting the values indicated under (a) we have 
 
 W 1 = 8 X 8 = 2.03 
 
 3 (10 + .5) 
 
 and for a coal having 70% of carbon the weight would be 1.42 pounds 
 per pound of coal. Calculating the oxygen to the equivalent of air, 
 
 23 : 100 :: 1.42 : x 
 x = 6.17 
 
 Hence the weight of air passing through unused is 6.17 pounds per 
 pound of coal. 
 
 From (a) and (b) therefore 
 
 Total air entering 16.47 pounds 
 
 Air unused 6.17 ' ' 
 
 Air used 10.30 
 
 16.47 
 
 10,30 
 
 = 1.60 Eatio of air entering to air used 
 
 (c) The Loss of Heat Passing Up the Chimney: The factors 
 which enter into the calculation of heat losses in chimney gases are (1) 
 the weight of the flue gas per pound of fuel, (2) the specific heat in 
 B.t.u. per pound, and (3) the rise in temperature or difference in tem- 
 peratures (t - t 1 ) between the entering air and the gases as they leave 
 the furnace. 
 
 (1) The weight of the gas per pound of fuel may be readily de- 
 rived from the formula for "W as developed under (a) and (b) above. 
 Letting W v represent the weight of the mixed gases per pound of pure 
 carbon, then by a similar procedure to that shown in equation (2) under 
 (a) and equation (3) under (b) we would have for the total weight of 
 all of the components per pound of carbon : 
 
 w = 11_C0 2 + 8 '0, + 7 CO + 7 N 2 
 
 3 (C0 2 + CO) 
 
 Or, since CO + N 2 = = 100 - - C0 2 - - 2 this expression may be still 
 further simplified to read: 
 
 w _ 4 C0 2 + 2 + 700 
 
 3 (C0 2 + CO) 
 
 Assuming the coal used as in (a) and (b) to have 70 per cent of carbon 
 (the carbon of the ash having been subtracted), then by substituting the 
 percentage values for the chimney gas as already indicated and multi- 
 
CALCULATION OF HEAT LOSSES 75 
 
 W - ^ X 10 + 8 + 700 x J0 _ 16 _ 62 
 
 plying by .70 we would have the weight of gases per pound of fuel : 
 >< 10 + 8 + 
 3 (10 + 0.5) 
 
 Therefore for (1) 
 
 W = = 16.62 pounds dry gases per pound of fuel. 
 (2) The specific heats of the various components, at constant 
 pressure in B.t.u. per pound, calculated for the interval 60F - 600F, 
 
 C0 2 = 0.222 
 
 2 = .217 
 CO = .245 
 
 N 2 = .2407 
 H 2 6 = .4673 
 
 From which it appears that an average specific heat of 0.24 for all 
 the constituents exclusive of water vapor may properly be applied. 
 Assuming, therefore, the (t - t 1 ) values of 60 entering and 600 leav- 
 ing, we have a total loss L for the dry gases thus : 
 
 L 16.62 X 0.24 X 540 
 L = 2154 B.t.u. 
 
 Assuming a heat value of 12,000 B.t.u. for the coal per pound as fired, 
 then the percentage loss, L 1 , would be, 
 
 X 100 
 
 12000 
 L 1 = = 17.95 per cent. 
 
 Other Losses: In obtaining a heat balance as in boiler tests, other 
 heat losses are taken account of. They include: 
 
 A. The latent heat of vaporization of moisture. 
 
 B. The heat of the water vapor passing off at the temperature 
 
 of the chimney. 
 
 C. The heat combustion of carbon to CO, instead of to CO,. 
 
 D. The unburned carbon in the ash. 
 
 A. The water from which the loss of heat is calculated is made 
 up of 
 
 (a) The total hydrogen of the coal burning to H.,0, that is 
 
 HX9. 
 
 (b) The free moisture of the coal. 
 
 (c) The moisture of the air as indicated by the relative 
 
 humidity. 
 
76 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 The sum of the three amounts of water referred to the unit of 1 
 pound of coal multiplied by the factor for the latent heat of vaporiza- 
 tion represents the heat loss in B.t.u. per pound of coal thus : 
 
 B.t.u. loss ] 
 
 per pound f = wt. of H 2 X 966 
 
 of coal J 
 
 B. Having found the weight of water as under A, the heat loss 
 due to rise in temperature from room temperature, t, to 212, and from 
 212 to temperature of flue gases, T, is found, using the specific heat 
 factor for the water vapor, .of 0.467, thus: 
 
 B.t.u. loss ] 
 
 per pound } = H,0 X (212 t) + H 2 X 0.467 X (T 212) 
 
 of coal J 
 
 C. The heat loss due to the burning of carbon to CO instead of 
 C0 2 is found by multiplying the weight of carbon thus entering into 
 the reaction per pound of coal, by the difference between the calorific 
 value of carbon burned to C0 2 and carbon burned to CO, thus : 
 
 B.t.u. loss from CO] 
 
 per pound j> = Wt. C. in CO X 10150 
 
 of coal J 
 
 D. The loss of heat due to combustible matter passing through 
 with the ash unburned is found by determining the combustible in the 
 ash as carbon, c, and referring it to the total refuse, r, in its proper pro- 
 portion, x, to the ash, a, of the original fuel thus : 
 
 C : r :: x : a 
 Having the value, x, in percentage of the original coal as fired, then, 
 
 Heat loss per pound \ _ _ 
 
 of coal from unburned carbon j 
 
 CHAPTER IV 
 
 LUBRICANTS. 
 
 "Next to the conservation of the world's fuel supply there is proba- 
 bly no subject of greater importance in the manufacturing world than 
 the control of waste power caused by imperfect lubrication and needless 
 friction. ***** Archbutt has stated that of the 10,000,000 h.p. in 
 use in the United Kingdom of Great Britain considerably more than half 
 this amount, 40 to 80 per cent of the fuel, is spent in overcoming fric- 
 
LUBRICANTS 77 
 
 tion, and that a considerable proportion of this power is wasted by im- 
 perfect or faulty lubrication."* 
 
 Any substance made use of for the lessening of friction is called 
 a lubricant. By its use the surfaces of sliding bodies are separated by 
 a thin film which permits of easier movement than if the surfaces were 
 in direct contact. Lubricants must, therefore, vary widely for the dif- 
 ferent kinds of work involved. For example, the "body" must be suited 
 to the load. Working temperatures, both high and low, must be pro- 
 vided for. Oxidizing or gumming must not be a property of the material, 
 and any tendency to corrode the metal surfaces must be absent. 
 
 Lubricants are derived from two main sources: 
 First, Oils of animal or vegetable origin 
 Second, Mineral oils. 
 
 Animal and Vegetable Oils: All oils of this class are saponifiable. 
 That is, they are compounds of fatty acids and glycerine. They decom- 
 pose to a considerable extent on long standing, setting free the fatty 
 acids. Many vegetable oils, as linseed oil, readily oxidize, forming a 
 gumming substance. Only non-oxidizable oils are suitable for lubrica- 
 tion. Among vegetable oils the best known illustrations are olive (sweet) 
 oil and castor oil. Among animal oils, lard oil is perhaps the most 
 common. 
 
 Mineral Oils: These oils are derived from petroleum by distilla- 
 tion. They will not saponify, having no combination of fatty acids, 
 and they will not oxidize to form "gumming" compounds. 
 
 The compounding of oils is an attempt to render a certain oil more 
 effective by mixing with another oil having slightly different properties. 
 Thus, mineral oils may be said to be compounded with an animal oil to 
 impart greater body or viscosity to the mixture ; or, a vegetable oil with 
 heavy body but too little fluidity, may be compounded with a mineral 
 oil to improve its property in that direction. Mineral oils are often 
 compounded with each other to produce certain desired properties. 
 Greases are mixtures of heavy oil residues or vaseline-like substances 
 with mineral soap, such as lime soap, to the extent of 30 to 40 per cent, 
 thus giving a mixture of great body for heavy machinery, shafting, 
 gears, etc. Finely pulverized mica or graphite is also similarly employed. 
 
 For high temperature service the problem becomes more difficult. 
 An oil must be selected which will not volatilize at the high temperature 
 employed. The principal tests in the examination of oils have for their 
 purpose the development of these various properties; for example, the 
 viscosity and body as shown by the viscometer, and specific gravity, the 
 flash point for high temperature use, acid or saponification number to 
 
 *C. F. Maberry, Jour. Ind. and Eng. Chem. II, 115. 1910. 
 
78 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 show whether or not the oil is compounded with animal or vegetable 
 material. 
 
 Methods for testing lubricating ores, therefore, include determina- 
 tions for 
 
 (a) Viscosity 
 
 (b) Specific gravity 
 
 (c) Flash and fire temperatures 
 
 (d) Saponification number 
 
 Because of their low cost and the ease with which they may be varied 
 to meet the different conditions as to load, speed and temperature, petro- 
 leum and the products which may be derived therefrom have come to 
 predominate in the entire field of lubricants. 
 
 Hydrocarbons of the general type, C n H 2n+2 or the paraffin series 
 are probably best suited for lubrication purposes. However, because 
 of the development of processes for distilling, cracking, and mixing it 
 would be impossible to prescribe a chemical composition to conform to 
 any specific type of carbon compounds. Doubtless some forms are more 
 unstable than others and as a rule, in service at high temperatures as 
 with automobiles, there is a tendency toward decomposition which is 
 almost always accompanied by the formation of free carbon. Promoters 
 of petroleum lubricants, however, who claim their special oils are with- 
 out any carbon in their composition, have more zeal than chemical sense. 
 
PART II 
 LABORATORY PROCESSES 
 
 CHAPTER V 
 
 INTRODUCTORY 
 
 Normal Solutions: If the reaction between one solution and an- 
 other can be gauged exactly as to the "end point", that is, if that point 
 can be noted where an exact balance exists between the two reacting 
 substances, we may make use of these solutions as media for making 
 chemical measurements, just as a mechanic uses a foot rule for measur- 
 ing lengths. Given, therefore, a solution of known value, that is, a 
 standard solution, and a reaction where the end point or chemical equi- 
 librium can be made visible to the eye by any means, we have a method 
 which can be used to measure other solutions of unknown value. When 
 a standard solution has its chemical value made up in terms of the 
 molecular weight of the substance in grams per liter, it is called a molal 
 solution. It is more convenient, however, to make up such solutions on 
 the basis of the hydrogen equivalent of the part of the molecule con- 
 cerned, in order to avoid the necessity of multiplying or dividing by 
 two where ions of different valencies interact. Thus, 
 
 2HC1 + Na 2 C0 3 = 2NaCl + H 2 C0 3 would call for two molecular 
 quantities of HC1 and one of Na,CO 3 or one of HC1 and y 2 of Na 2 C0 3 . 
 Again, 
 
 HC1 + Na 2 C0 3 = NaCl + NaHC0 3 would call for one full mole- 
 cular quantity of HC1 and y 2 of the molecular value for the Na,C0 3 . 
 By common agreement the single hydrogen equivalent has been adopted 
 as the basis, and solutions of this kind are called normal solutions. 
 Hence, a normal solution of the first substance, HC1, has exactly 36.46 
 grains per liter. A normal solution of the second has exactly 53.00 
 grams or y 2 of the molecular weight, 106.0, of sodium carbonate per 
 liter. Where solutions of less strength are needed, tenth or hundredth 
 
 79 
 
10 
 
 8o THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 normal solutions are used, expressed thus: N / 10 or N / ]00 . Thus, N / 
 sodium carbonate has 5.300 grams of the pure substance per liter and 
 each c.c. contains .0053 gram of the alkali. 
 
 It is important that the full significance and value of the processes 
 involving normal solutions be well understood at the outset of the work. 
 The preliminary experiments following will help to this end. 
 
 PRELIMINARY EXPERIMENTS * 
 
 EXERCISE I 
 
 Standard Sodium Carbonate: The preparation of N / 10 sodium car- 
 bonate solution is carried out as follows : 
 
 Clean and dry a porcelain crucible or small porcelain dish, then 
 ignite it lightly and cool down to room temperature, putting into the 
 desiccator at about 150. Weigh accurately and add about six grams, 
 more or less, of pure, dry sodium carbonate. Eaise to a red heat, short 
 of melting, and cool in a desiccator. Counterpoise upon the balance in 
 such a manner that by removing with a clean knife blade or spatula the 
 excess of material, there shall remain in the crucible exactly 5.300 grams 
 of the carbonate. Empty the carbonate into a No. 3 beaker and add 
 50 or 100 c.c. of distilled water. Einse out the crucible also a number 
 of times, adding the washings to the beaker. After solution of the 
 carbonate is complete, pour the contents of the beaker into a liter meas- 
 uring flask. Einse out the beaker thoroughly, transferring the washings 
 to the flask and make up finally to the mark. The temperature of the 
 water employed for making up to volume should not exceed 20 C. 
 Stopper and mix by shaking until an absolute certainty of uniform 
 distribution of the solution is attained. If the sodium carbonate is pure 
 and the proper care in regard to transferring, mixing, temperature, etc., 
 has been observed, we should now have a strictly N / 10 solution. To test 
 its accuracy, obtain from the instructor some of the ready prepared N / 10 
 hydrochloric acid solution and proceed as follows. 
 
 Measure about 20 c.c. of the sodium carbonate from a burette into 
 a clean beaker. Add about 20 c.c. of water and two drops of methyl 
 orange solution. Titrate very slowly with N / 10 hydrochloric acid 
 from a burette. Add acid drop by drop until the yellow turns to an 
 orange color. More acid will make the solution pink, but this is too 
 far the intermediate orange tint denotes neutrality. More accurate 
 results will be obtained if the solutions are titrated back and forth until 
 one drop of either solution will change the color of the indicator. Eepeat 
 this titration three times and average the results. The quantity of acid 
 required should not vary from the solution taken by more than 0.1 
 c.c. If there is a greater difference than this, the strength of the 
 sodium carbonate solution may be calculated from the known hydro- 
 
STANDARD SOLUTIONS 81 
 
 chloric acid solution. This correction is known as the N / 10 factor. The 
 factor must be taken into consideration whenever the sodium carbonate 
 solution is used. The exactly N / 10 solutions are much to be preferred 
 where a large number of determinations are being made. What applies 
 to the sodium carbonate solution is equally true with all standard solu- 
 tions that are used. From the N / 10 sodium carbonate solution make a 
 N / 50 sodium carbonate solution. 
 
 EXERCISE II 
 
 Standard Sulphuric Acid: Prepare a N / 10 solution of sulphuric 
 acid by means of the N / 10 Na 2 C0 3 solution as follows : 
 
 Measure about 3% c.c. of pure concentrated sulphuric acid into a 
 flask containing 1050 c.c. of distilled water. Mix thoroughly and fill a 
 50 c.c. burette with the solution. Measure 20 c.c. from the burette into 
 a clean beaker, add about 20 c.c. of water and 2 drops of methyl orange. 
 Titrate slowly with N / 10 sodium carbonate solution from a burette until 
 the end reaction is shown by the first change of color from pink to 
 orange. Repeat the titration as before, being careful to note the correct 
 color for the end point. The acid solution is probably too strong. If 
 the titration with N / 10 sodium carbonate requires, say, 21 c.c. instead 
 of 20 c.c., then in such case 20 c.c. of acid would need to be diluted to 
 21 c.c. to make an exact balance to the alkali solution. Similarly 200 
 c.c. would need to be diluted to 210 c.c. and the dilution for any amount 
 would be indicated by the proportion 
 
 20 : 21 :: 1000 : x 
 
 Hence, in the above example, measure an exact 1000 c.c. of the trial 
 acid and add 50 c.c. of pure water to it. Test the accuracy of the result- 
 ing solution with N / 10 sodium carbonate as before. 
 
 EXERCISE III 
 
 Determination of Sulphur: (Consult also the description for the 
 determination of sulphur under Proximate Analysis of Coal, p. 103.) 
 
 Measure out 10 c.c. of the x / 10 sulphuric acid solution and make up 
 to 100 c.c. Measure carefully 10 c.c. of this solution into a 100 c.c. 
 cylinder and fill two-thirds full of water. Add 5 drops of pure concen- 
 trated hydrchloric acid, make up to the 100 mark, pour into an Erlen- 
 meyer flask and add about 0.2 to 0.4 gram of special Barium Chloride 
 pow r der (BaCl 2 + H 2 C 2 4 ) and shake thoroughly. Warm slightly to 
 prevent the crystallization of the oxalate salt. Let stand for 15 20 
 minutes with occasional shaking. Take the solution to the photometer 
 room. 
 
82 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 Light the gas, adjusting to such a height that the tip of the flame 
 just appears above the edge of the metal chimney.* Turn out all the 
 lights in the room. Arrange the apparatus so that looking down the 
 graduated tube the flame is seen as a small bright point in the center 
 of the bottom of the tube. Now run in the solution, with barium sul- 
 phate in suspension, until the point of illumination just disappears from 
 sight. Read off the height on the graduated tube, and repeat twice. 
 If the column is less than 60 or more than 160 m.m. in depth, reject the 
 test and start anew using double or half the quantity of solution under 
 test, making up to 100 c.c. in each case as before. 
 
 On page 107 will be found a curve on which is indicated the number 
 of grams of sulphur per 100 c.c. of solution corresponding to the various 
 heights. Calculate the weight of sulphur indicated to sulphuric acid. 
 Note that the actual amount of the N / 10 solution taken for the test is 1 c.c. 
 
 One cubic centimeter of N / 10 sulphuric acid has what weight of acid 
 present ? 
 
 How much sulphur? 
 
 What would be the equivalent amount of hydrochloric acid? So- 
 dium Carbonate? Calcium carbonate? 
 
 EXERCISE IV 
 
 Standard Calcium Chloride and Soap Solutions: Measure from a 
 burette into a clean No. 2 beaker 40 c.c. of N / 10 hydrochloric acid. What 
 equivalent does it contain in terms of sodium carbonate ? What equiva- 
 lent in terms of calcium carbonate ? Weigh carefully 0.210 gram of 
 pure calcium carbonate powder and add it to the 40 c.c. of N / 10 hydro- 
 chloric acid. Cover with a watch glass and heat for a few minutes till 
 all action has ceased. Transfer to a liter flask. Wash out the beaker 
 thoroughly with distilled water, transferring the washings to the flask. 
 Make up to the mark and mix thoroughly by shaking. Allow the con- 
 tents to stand quietly until all undissolved material has settled to the 
 bottom. Siphon off half or more of the clear solution into a suitable 
 flask and label "STANDARD CALCIUM CHLORIDE SOLUTION". Since one 
 c.c. of a N / 10 solution is equivalent to one c.c. of any other N / 10 solution, 
 we have in the above solution 40 c.c. of a N / 10 CaCl 2 solution. Although 
 calcium carbonate is not soluble in water, the 40 c.c. of N / 10 calcium 
 chloride is equivalent to the amount of calcium carbonate in 40 c.c. of a 
 theoretical N / 10 solution of calcium carbonate. Since in one c.c. of a 
 
 *A tungsten lamp is to be preferred where available. It should be 3 to 4 volt, 
 such as may be obtained from 2 dry cells with the bulb of clear glass without flaw. 
 
STANDARD SOAP SOLUTION 83 
 
 N / 10 solution of calcium carbonate there are .005 grams of calcium car- 
 bonate, in the 40 c.c. of hydrochloric acid solution or the liter of solution 
 there are .2 grams of calcium carbonate. The standard calcium chloride 
 solution, therefore, has a value of 200 parts per million in terms of 
 calcium carbonate. 
 
 The standard soap solution is obtained from the stock shelf. It is 
 prepared by dissolving 10 grams of castile soap in 100 c.c. of 80 per 
 cent alcohol. After standing for several days it is further diluted with 
 70 per cent alcohol to a point where 5 or 6 c.c. of it as measured from 
 a burette will produce a permanent lather when added as directed below 
 to 20 c.c. of the standard calcium chloride solution. This will require 
 usually a dilution up to 900 or 1000 c.c. 
 
 Standardization of the Soap Solution: Measure 20 c.c of the stand- 
 ard calcium chloride solution into a 250 c.c. glass stoppered bottle and 
 add 30 c.c. of distilled water. Run in from a burette the standard soap 
 solution 0.4 or 0.5 c.c. at a time, shaking the bottle vigorously after each 
 addition. Lay the bottle on its side after each shaking and note if the 
 lather remains. The end point is taken where the lather remains over 
 the entire surface of the water for five minutes after shaking. Make 
 three tests of the standard calcium chloride solution as above prepared. 
 Repeat the process, using 10 c.c. of the calcium chloride solution and 
 making up to the same volume (addition of 40 c.c. water) as before. 
 By thus establishing a number of points as for 10, 15, 20 and 25 c.c., 
 in which the required soap solution has been determined, a curve for 
 the strength of the soap solution is developed as illustrated in the chart, 
 Fig. 14. 
 
 The hardness of a water is due to any mineral constiuents in solu- 
 tion other than compounds of sodium, potassium, ammonium, etc., mem- 
 bers of the first or soluble group. Upon the addition of soap to a hard 
 water there are formed insoluble soaps of calcium, magnesium and iron, 
 which are precipitated in curdy granules. When all of these constituents 
 are precipitated the water is soft. It is this action of soap which per- 
 mits of its use in a standard solution for measuring the total hardness. 
 
8 4 
 
 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 O 
 
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 A 
 
 ^ 
 
 
 
 a 
 
 
 
 
 6 
 
 
 
 
 / 
 
 ^ 
 
 
 
 \ 
 
 
 
 CUBIC CENTIMETERS SOAP SOLUTION. 
 
 Fig. 14. Development of the curve for a standard soap solution, with the 
 points located as follows : 
 
 Point No. i, using 10 c.c. CaCl 2 sol. 
 Point No. 2, using 15 c.c. CaCU sol. 
 Point No. 3, using 20 c.c. CaCl 2 sol. 
 Point No. 4, using 25 c.c. CaCl 2 sol. 
 
WATER ANALYSTS 85 
 
 EXERCISE V 
 
 Determination of Calcium Sulphate in Water: Get a bottle of 
 unknown "A" for analysis. Add 25 c.c. to a clean beaker with a 
 pipette, then run in 10 c.c. of N / 10 sodium carbonate solution. Boil for 
 5 minutes on a sand bath, then filter into a clean beaker. Wash well 
 with hot water, saving all the washings until the liquid leaving the fun- 
 nel is neutral to litmus paper. Now add 2 drops of methyl orange to 
 the filtrate and washings and titrate with N / 10 hydrochloric acid. 
 
 The equation representing the reaction between sodium carbonate 
 and calcium sulphate is 
 
 CaS0 4 + Na 2 C0 3 = CaC0 3 + Na 2 S0 4 . 
 
 Since the titrated sodium carbonate is the balance of the 10 c.c. 
 remaining unchanged after the reaction has taken place, the difference 
 between this amount and the 10 c.c. originally added represents the 
 amount of sodium carbonate taking part in the reaction, and from this, 
 remembering always the equivalent of normal solutions, compute the 
 weight of calcium sulphate present. Since a 25 c.c. sample was taken, 
 how many grams per liter did the solution contain? How many parts 
 per million? How many grains per U. S. Gallon?* 
 
 Calculate also the lime, in grains per gallon, equivalent to the 
 calcium sulphate present. Calculate also the equivalent of calcium 
 carbonate in grains per gallon corresponding to the sulphate ion present. 
 From the amount of hydrochloric acid used, calculate the sodium chlo- 
 ride (NaCl) formed. 
 
 2HC1 + Na 2 C0 3 = 2NaCl + C0 2 + H 2 0. 
 
 Perform all these calculations in the note book for inspection and 
 reference. 
 
 CHAPTER VI 
 
 BOILER WATER ANALYSIS 
 EXERCISE I 
 
 Excess or Free Carbon Dioxide: By this is meant the carbon 
 dioxide held in solution by the water. It is not scale forming material, 
 but in water treatment it behaves as so much temporary hardness, and 
 the amount present must be determined in order to gauge correctly the 
 quantity of reagent required in the treatment. The "excess" carbon 
 dioxide is readily taken up by calcium hydroxide, Ca(OH) 2 , forming 
 *Milligrams per liter or parts per million X .0583 = grains per U. S. gallon. 
 See p. 24. 
 
86 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 calcium carbonate ; or by sodium carbonate, forming sodium bicarbonate. 
 So long as there is present free carbon dioxide, it acts toward phenolph- 
 thalein as acid, decolorizing the same. The first excess of Na 2 C0 3 be- 
 yond the point of absorption of the C0 2 is denoted by a pink coloration 
 of the indicator. 
 
 Procedure. With the graduated cylinder measure 200 c.c. of the 
 water into a No. 3 (350 c.c.) beaker. Add a few drops of phenolphtha- 
 lein as indicator and titrate to the end point with N / 50 sodium carbonate 
 free from bicarbonate. The number of c.c. used times 5 represents the 
 equivalent or excess of C0 2 in parts per million, but measured in terms 
 of calcium carbonate. 
 
 EXERCISE II 
 
 Total Alkalinity and Temporary Hardness: Temporary hardness 
 is due to the calcium, magnesium, and iron held in solution in the form 
 of bicarbonates. They are readily broken down by dilute acids and, 
 until so destroyed, are alkaline towards methyl orange indicator. 
 
 Procedure. Measure 200 c.c. of the water into a No. 3 beaker, 
 add a few drops of methyl orange and titrate with N / 10 sulphuric acid. 
 From the number of c.e. used can be calculated the equivalent in parts 
 per million of temporary hardness measured in terms of calcium car- 
 bonate. Note that to calculate the value in c.c. per liter we would need 
 to multiply the titration by five. The equivalent value for N / 10 sul- 
 phuric acid in terms of calcium carbonate is 0.005 gram per c.c. of 
 solution. Hence, five times the number of c.c. per liter would represent 
 the calcium carbonate in milligrams per liter. That is, 25 times the 
 titration number represents milligrams per liter or parts per million of 
 calcium carbonate equivalent. 
 
 Note : If under Exercise V below sodium carbonate is found to be 
 present as negative hardness, the temporary hardness is equal to the 
 total alkalinity minus the negative hardness. If there is no negative 
 hardness the temporary hardness is equal to the total alkalinity. 
 
 EXERCISE III 
 
 Magnesia: Use the solution from Exercise II above. Cover the 
 beaker with a watch glass, boil for fifteen minutes, add 50 c.c. of satu- 
 rated lime water and allow to stand at near the boiling temperature for 
 about fifteen minutes. Filter into a 250 c.c. flask, wash with boiled 
 distilled water and add water so that the volume at room temperature 
 will be 250 c.c. Titrate 100 c.c. with N / 10 sulphuric acid, using the 
 methyl orange indicator. Make at the same time the same determina- 
 tion, using pure distilled water in place of the water analyzed. The 
 
WATER ANALYSIS 87 
 
 difference between the two titrations is the amount of sulphuric acid 
 which would have been neutralized by the calcium hydroxide, which 
 has precipitated the magnesium from the water. Since the amount 
 titrated, 100 c.c., is equal to 2/5 of the 250 c.c., it must also be equal to 
 2/5 of the original 200 c.c. Then the difference between the titrations 
 multiplied by (5/2x5x5) equals the equivalent in parts per million of 
 the magnesia in the water measured in terms of calcium carbonate. 
 
 Note: Because of the solubility of magnesium carbonate in the 
 presence of alkali bicarbonates, it is necessary to precipitate the mag- 
 nesium as hydroxide. In w T ater treatment, therefore, the magnesium 
 bicarbonate requires double the amount necessary to simply bring it to 
 the carbonate stage. (See p. 16, Part I). 
 
 EXERCISE IV 
 
 Permanent Hardness: Boil in a porcelain dish 500 c.c. of the 
 water for about 10 minutes and add* 25 c.c. of N / 10 "soda reagent" 
 (equal parts of sodium hydroxide and sodium carbonate) and boil fur- 
 ther to about y 2 volume. Filter, wash and make up to 250 c.c. Titrate 
 100 c.c. of this solution with N / 10 sulphuric acid, using methyl orange 
 as an indicator. The amount of original water used is then 200 c.c. 
 since the 100 c.c. used is 2/5 of the 250 c.c. and consequently 2/5 of the 
 500 c.c. The difference between this titration and the amount of acid 
 equivalent to 25 c.c. N / 10 soda reagent multiplied by (5x5) represents 
 the equivalent of permanent hardness in parts per million measured in 
 te,rms of calcium carbonate. Calculate also the amount in parts per 
 million of the sodium sulphate formed by the reaction and refer the 
 result for use under exercise number IX. 
 
 In the reaction, as with "soda reagent" for example 
 
 CaSO 4 + Na 2 C0 3 (25 c.c.)= Na 2 S0 4 + CaCO 3 + Na 2 C0 3 (25 x) c.c., 
 
 it is seen that part of the N / 10 sodium carbonate has changed over to 
 sodium sulphate. The extent of this change is dependent, of course, 
 upon the quantity of calcium sulphate, magnesium sulphate, etc., pres- 
 ent in the water and the measure of the change is indicated by the titra- 
 tion of the nitrate. It is to be noted again that in so far as magnesium 
 sulphate may be present, the magnesium carbonate formed is soluble to 
 a considerable extent, hence the more insoluble magnesium hydroxide 
 is provided for by the use of the "soda reagent", which is part sodium 
 hydroxide. 
 
 Some waters will give a titration in the nitrate which is greater in 
 amount than the quantity of soda reagent added. This condition is 
 designated as negative hardness. 
 
88 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 EXERCISE V 
 
 Negative Hardness: Throughout this region a very large percent- 
 age, especially of the deep wells, yield waters of Class I, as described on 
 page 11. Such waters have no sulphates of calcium or magnesium pres- 
 ent. They have, however, some free sodium bicarbonate instead, which 
 indicates that some such reaction as indicated in Exercise IV above has 
 taken place while the water was percolating through the ground. The 
 treatment, therefore, prescribed above would result simply in the addi- 
 tion of more alkali. Hence, the excess of acid required over the 10 c.c. 
 of alkali added would be a measure of the free sodium carbonate or 
 "negative hardness" present. Multiplying by (5x5.3) would give the 
 weight in milligrams per liter of Na 2 C0 3 . Calculate the negative hard- 
 ness in terms of calcium carbonate in order to obtain the temporary hard- 
 ness. Determine the amount of negative hardness in the laboratory tap 
 water. 
 
 EXERCISE VI 
 
 Total Hardness: The total hardness of a water may be derived 
 (a) from the data which has resulted from experiments II and IV above, 
 and (b) from the soap test. It is well to use both sources of information 
 as a check. 
 
 (a) Under experiment II there will be measured the amount of 
 temporary or bicarbonate hardness, that is, the amount of calcium, 
 magnesium and iron present as bicarbonates, but measured all together 
 in terms of calcium carbonate by the titration with N / 10 hydrochloric 
 acid or sulphuric acid. 
 
 Under experiment IV there will be indicated the amount of sul- 
 phate or chloride hardness; that is, the amount of calcium, magnesium 
 or iron which may be present in the form of the sulphates or chlorides 
 of these elements, but measured again in the equivalent of calcium 
 carbonate. Be sure that experiment No. V has been taken into this 
 account, for, if free sodium bicarbonate is present, there will be 110 
 permanent but only temporary hardness to enter into the total hard- 
 ness. The sum of the temporary hardness and permanent hardness, (if 
 any), given in terms of calcium carbonate, represents the total hardness. 
 
 (b) Make a determination of total hardness by means of the 
 standard soap solution as follows : 
 
 Measure 50 c.c. of the water into a No. 3 beaker, add a few drops 
 of methyl orange and titrate with N / 10 sulphuric acid to the end point. 
 Transfer the water thus neutralized to the shaking bottle used for the 
 soap test and run in from a burette, the standard soap solution, a few 
 tenths of a cubic centimeter at a time, shaking vigorously after each 
 addition. The end point is taken in the same manner by noting where, 
 
USE OF SOAP SOLUTION 
 
 89 
 
 upon laying the bottle on its side after shaking, the lather remains for 
 five minutes. With waters containing magnesium salts care must be 
 taken to avoid mistaking the salts of magnesium end point. After the 
 titration is apparently finished read the burette and add 5 c.c. of soap 
 solution. If the end point was due to magnesium the lather disappears. 
 Continue the addition of soap solution until the true end point is reached. 
 Upon the page of dimension paper herewith, locate a curve which 
 represents the strength of the soap solution used and from this read the 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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 CUBIC CENTIMETERS SOAP SOLUTION 
 
 FIG. 15. PLOTTING A CURVE FOR STANDARD SOAP SOLUTION 
 
 Showing the value in parts per million of CaCOs. 
 
90 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 amount of parts per million in terms of calcium carbonate. How does 
 the amount compare with the total hardness as derived under (a) above? 
 
 EXERCISE VII 
 
 Determination of Total Sulphates. Into a 100 c.c. cylinder meas- 
 ure 50 c.c. of water and add 2 or 3 drops of concentrated hydrochloric 
 acid. Make up to exactly 100 c.c. in the graduated cylinder. Pour 
 into an Erlenmeyer flask of about 200 c.c. capacity and add Special 
 Barium Chloride as in Exercise II of Section II for the determina- 
 tion of sulphuric acid. Warm slightly. After standing 15-20 minutes, 
 read in the photometer as directed in Preliminary Exercise III of Chap- 
 ter II. Refer to the chart on page 107 for the weight of sulphur indi- 
 cated by the photometer reading. Calculate to sulphuric acid thus 
 
 32 : 142 : : wt. of S. : Na 2 S0 4 
 EXERCISE VIII 
 
 Determination of Total Chlorides: Measure accurately 50 c.c. of 
 water by means of a 50 c.c. pipette into a porcelain dish. Add about 1 
 c.c. of potassium chromate solution and titrate with N / 100 silver nitrate 
 solution, until the yellow color gives place to the first permanent trace 
 of reddish brown, do not wait for a red tint to appear. Fill another 
 porcelain dish with 50 c.c. of distilled water and add 1 c.c. of the indi- 
 cator. Use this as a standard of comparison. The first tinge of brown- 
 ish red that can be distinguished in the titrated solution is to be taken 
 as the end point. 
 
 The reactions involved are 
 
 2AgN0 3 + K 2 Cr0 4 2KN0 3 + Ag 2 Cr0 4 . 
 
 The silver chromate is a red precipitate, but as long as there is any 
 soluble chloride in solution, this breaks up the chromate as follows 
 
 Ag 2 Cr0 4 + CaCl 2 = 2AgCl + CaCrO 4 . 
 
 Thus, the first tinge of pink shows that the chlorine of the chloride has 
 all been precipitated. From the volume of silver nitrate used to this 
 point, calculate the weight of chlorine in the 50 c.c. taken thus 
 
 Vol. N /ioo AgN0 3 X .0003545 = wt.CL in 50 c.c. 
 
 and 0.0005845 X the vol. N / 100 AgN0 3 = wt. NaCl in 50 c.c. of the water. 
 Multiplying further by 20 will give the weight per liter. From this is 
 indicated, by referring to milligrams, the milligrams per liter or parts 
 per million. 
 
ALKALINITY 91 
 
 EXERCISE IX 
 
 Total Alkalies: The total alkalies are considered as being made 
 up of all the sulphate not combined as permanent hardness and all of 
 the chlorides. It is true that small amounts of other alkali salts, as 
 sodium nitrate, are present and occasionally some of the chloride is 
 present as magnesium or calcium chloride; but, for the scope of this 
 work and for ordinary technical requirements, it is quite sufficient to 
 consider the total alkalies as being constituted as above indicated. 
 
 Procedure : From the total sulphate as determined under No. VII 
 and calculated to sodium sulphate, subtract the sulphate hardness as 
 found under No. IV and which was there calculated also to the equiva- 
 lent of sodium sulphate for this purpose. The remainder is the amount 
 of alkalies existing in the water in the form of sodium sulphate. To 
 the above should be added the total chloride results under No. VIII, 
 calculated to sodium chloride. 
 
 If free sodium carbonate or negative hardness was developed under 
 No. V then this also in the form of equivalent sodium carbonate should 
 be added as a third constituent of the alkalies. 
 
 The sum of these various constituents, referred in each instance to 
 parts per million, is to be taken as the total alkalies in parts per million. 
 Calculate this sum also to grains per U. S. Gallon. 
 
 EXERCISE X 
 
 Examination of a Treated Water: 1. If the water has been under 
 treated, it is possible to determine as with an untreated water the 
 amounts of lime and soda still needed to soften water. 
 
 2. In case excess of soda ash has been added, the permanent hard- 
 ness will be negative; and, if the water has no sodium carbonate present 
 originally, 1.06 times the negative hardness expressed as parts per mil- 
 lion of calcium carbonate represent the excess of sodium carbonate which 
 has been added to the water. 
 
 3. In most cases, however, a treated water is alkaline to phenolph- 
 thalein, in which case 200 c.c. is titrated with N / 10 sulphuric acid, to the 
 end point with phenolphthalein and then on to the end point with methyl 
 orange. 
 
 If the amount of acid needed to give the end point with the phe- 
 nolphthalein is more than half that which is needed to give the end 
 point with methyl orange, an excess of lime is present. If the difference 
 between the two qauntities be subtracted from the number of c.c. for 
 the phenolphthalein end point, the result shows the calcium carbonate 
 equivalent in parts per million of the excess of pure lime, CaO. This 
 equivalent multiplied by 56 gives the parts per million of CaO and this 
 result multiplied by .0583 gives the amount in pounds per 1000 gallons. 
 
92 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 EXERCISE XI 
 
 Summary of results and calculations: The character of a water is 
 shown by assembling in tabular form the various ingredients grouped 
 in a manner to indicate the total scale-forming and the total foaming 
 ingredients, as called for in the accompanying outline. This summary 
 calls for the various results in grains per gallon, and the order and 
 grouping is that of the exercises I to X. 
 
 The calculations for the requisite amount of reagents to remove the 
 scaling ingredients involve simply the calculation from the determined 
 equivalent of calcium carbonate over to the proper reacting substance, 
 thus 
 
 Since one equivalent of excess C0 2 , one equivalent of temporary 
 hardness or one equivalent of magnesium requires one equivalent of 
 calcium oxide for its removal from the water, 0.56 times the sum of the 
 calcium carbonate equivalent of excess carbon dioxide, temporary hard- 
 ness, and magnesium represents the number of parts per million of pure 
 lime CaO, necessary to remove these difficulties. 
 
 1.06 times the calcium carbonate equivalent of the permanent hard- 
 ness is the number of parts per million of sodium carbonate, Na 2 C0 3 , 
 necessary to remove the permanent hardness. 0.0583 times the quanti- 
 ties in parts per million gives the pounds per thousand gallons needed. 
 The results above are for pure lime and sodium carbonate. Commercial 
 lime and soda ash must be analyzed to determine the amounts of pure 
 lime and sodium carbonate which they contain. 
 
 Note: As an aid to calculations and a correct designation of the kind of 
 alkalinity present the following table will be found helpful: 
 
 Letting P t stand for the titration when using phenolphthalein and M o for 
 the titration when using methyl-orange, then, 
 
 When P t = M o there are present hydroxides only. 
 
 " P t < M o > y 2 M o " " " hydroxides and normal carbonates. 
 " P t = y 2 M o " " " normal carbonates only. 
 
 " P t < l / 2 M o " " " normal carbonates and acid carbonates. 
 
 " P t = Mo " " " acid carbonates only. 
 
UNIVERSITY OF ILLINOIS 
 DEPARTMENT OF APPLIED CHEMISTRY 
 Analysis of Boiler Water from 
 
 No 
 
 Sample Taken 191. 
 
 Free C0 2 
 as CaCOs Equiv 
 
 Total Alkalinity as 
 CaCOs Equiv 
 
 Temporary hardness as 
 CaCOs Elquiv 
 
 Negative hardness as 
 CaCOs Equiv 
 
 Magnesium as 
 CaCOs Equiv 
 
 Permanent hardness as 
 CaCOs Equiv 
 
 Total scale forming 
 material 
 
 Alkalies as Na 2 S0 4 
 Alkalies as NaCl 
 Alkalies as Na 2 CO 3 
 
 Parts per j Grains per 
 million gallon 
 
 Requiring for treatment 
 of 1000 gallons 
 
 Gallons of 
 saturated 
 CaO Sol. 
 
 Ibs. of 99.0 
 % Soda Ash 
 
 Remarks 
 
 By 
 
 93 
 
CHAPTER VII 
 THE PROXIMATE ANALYSIS OF COAL. 
 
 Introduction: The procedure as here outlined for the proximate 
 analysis of coal follows substantially the final report on methods of 
 analysis as adopted by the joint committee of the American Chemical 
 Society and the American Society for Testing Materials. The prelimi- 
 nary report of this committee published in the Journal of Industrial 
 and Engineering Chemistry for June 13, Vol. 5, p. 17, contains much 
 detail of value relating to sources of error and general conditions to be 
 observed in the procuring of accurate results. The final report is in a 
 much more condensed form and is intended as a guide for every-day 
 procedure in connection with coal contracts, and inspection. This was 
 printed as the report of Committee E-4 and presented at the annual 
 meeting of the American Society for Testing Materials, June, 1915. 
 
 EXERCISE I. 
 
 Moisture Loss on Air Drying: The sample as prepared for the 
 laboratory should be four or five pounds in amount and transmitted in 
 an air tight container. If the directions for sampling with regard to, 
 the fineness of division have been observed the laboratory sample will 
 be approximately 4-mesh or % inch in the diameter of the largest 
 particles. 
 
 Spread the sample on a tared pan about 18" x 18" x 1%" in depth. 
 Weigh and air dry at room temperature or in a special drying oven 
 through which a current of air is circulated and in which the tempera- 
 ture is maintained at 15 to 25 Fah. above that of the room. Weigh 
 again after twelve hours. The moisture content should now be in 
 approximate equilibrium with the moisture of the air. This will mean 
 a moisture factor of from 3 to 5 per cent. It may be indicated by the 
 fact that a continuation of the drying process will not show a loss of 
 more than 0.1 per cent per hour. Note the loss of moisture 011 air- 
 drying and calculate to per cent of the entire sample. 
 
 Working Sample: Pass the air died sample entire at once after 
 final weighing, through a grinder of the coffee mill type set to grind 
 to about 20 mesh. Immediately after passing through the grinder, 
 spread out on a tray and with a spoon take from various parts a 60 
 gram sample and place directly in a rubber-stoppered bottle and label 
 "For Total Moisture". 
 
 Thoroughly mix the main portion of the sample, reduce by means 
 of a riffle to about 60 grams. Pulverize to 60 mesh on the bucking 
 board, passing all of the material through the sieve. Transfer to a four- 
 ounce rubber stoppered bottle and label "Laboratory Sample for Coal 
 Analysis". 
 
 94 
 
MOISTURE AND ASH 95 
 
 EXERCISE II. 
 
 Total Moisture: In a dry glass capsule with ground glass cover 
 weigh out 5 grams of the 20-mesh sample labeled "For Total Moisture". 
 Heat with the cover off for iy 2 hours in an oven maintained at 104 to 
 110 C. Cool in a desiccator over concentrated sulphuric acid, sp, gr. 
 184. "Weigh. Calculate the moisture thus found to the percentage it 
 would be of the original coal before air drying and add to the air-drying 
 loss, thus, subtract the percentage loss on air-drying from 100 and 
 multiply by the oven drying loss to find the percentage to be added, or 
 as a formula: 
 
 \ s ! 
 
 -f 
 
 J.UU 
 
 in which (a) is the moisture loss on air-drying and (a 1 ) is the loss on 
 drying the air-dry sample at 104 110 C. 
 
 Moisture in the Laboratory Sample: Determine the moisture on 
 the 60-mesh laboratory sample, by weighing out 1 gram in a glass cap- 
 sule as in Exercise II and drying with the cover off at 104 110 C. 
 for one hour. Replace the cover, cool in the desiccator and weigh. The 
 loss of weight is the amount of water in the sample. Save for ash 
 determination. 
 
 EXERCISE III. 
 
 Ash: Transfer the 1 gram of coal remaining in the glass capsule 
 from the moisture determination to a porcelain crucible. Place on a 
 triangle 2 or 3 inches above the tip of a flame which has been turned 
 down to about 2 inches in height. It can be left in this condition with- 
 out attention for 15 or 20 minutes, when most of the carbonaceous mat- 
 ter will have been burned off. Lower the crucible to within 14 or % 
 inch of the flame and leave without attention for an equal length of 
 time. Occasional stirring with a platinum wire will facilitate the oxida- 
 tion. Finally place the crucible on the triangle in an inclined position 
 so as to facilitate the circulation of air currents over the ash; apply 
 the blast flame to the bottom of the crucible for 5 to 10 minutes or until 
 the ash does not lose in weight upon further blasting. Cool in the 
 desiccator and weigh. Subtract the weight of the crucible and compute 
 the weight of the ash to percentage of air dry coal. 
 
 EXERCISE IV. 
 
 Volatile Matter, Official Method: The standard method for deter- 
 mining the volatile matter in coal as indicated by the joint committee 
 on coal analysis in the Journal of Industrial and Engineering Chemis- 
 try, June, 1913, prescribes the use of a platinum crucible with capsule 
 
96 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 cover fitting inside of the crucible; that is, telescoping % to 1/4 of an 
 inch, instead of an ordinary cover resting on the upper edge. The 
 crucible with 1 gram of coal is placed in a muffle maintained at 950 C. 
 (20 C.) A vertical electrically heated muffle is easy of construc- 
 tion and greatly to be preferred for this work. On account of the 
 variation in pressure and heating value of city gas it is 1 practically 
 impossible to obtain consistent results with the Bunsen or Meker burn- 
 ers. A muffle heated by gas and maintained at the proper temperature 
 is much to be preferred to heating by the direct flame. 
 
 On account of the expense of platinum the use of a porcelain, cru- 
 cible is necessary in class work as indicated below. It is to be noted that 
 any method which retards the transmission of heat to the coal will result 
 in a lower indicated amount for volatile matter, and a correspondingly 
 higher percentage for fixed carbon. To overcome this discrepancy, 
 therefore, the porcelain crucible is put directly into a highly heated 
 chamber and the heat applied from the first at or above the prescribed 
 temperature. In this manner the results should check the official method 
 within 0.5 per cent. The volatile matter values will be found consistently 
 lower than percentages obtained by the official method by about that 
 amount. 
 
 Porcelain Crucible Method: Select a porcelain crucible with well 
 fitting cover, ignite, with cover, in the flame of a Bunsen burner to a 
 dull red heat, cool in the desiccator and weigh. Place a nichrome triangle 
 over a blast lamp and over the triangle place an inverted 20 gram assay 
 crucible with the bottom ground off, exposing a hole approximately one 
 inch in diameter. "When this apparatus is heated to as high a tempera- 
 ture as possible, remove the inverted crucible, put in place the porcelain 
 crucible with cover on containing one gram of air-dry coal. Continue 
 the heating for seven minutes and at the end of this period turn off the 
 flame and remove the assay crucible but do not disturb the cover of the 
 porcelain crucible until the same has been reduced below a red heat. 
 Transfer to a disiccator, cool and weigh with the cover. The loss in 
 weight minus the moisture present is the weight of volatile matter. 
 
 EXERCISE V. 
 
 Fixed Carbon: The sum of the percentages for moisture, (on the 
 air dry or working sample) ash, and volatile matter, subtracted from 
 100, will leave as a remainder the percent of fixed carbon in the air dry 
 coal. 
 
 Calculations: Calculate each value for the air dry sample to per- 
 centages of dry (moisture free) coal by dividing each by 1.00 the 
 weight found for that constituent. 
 
 Calculate to the "as received" basis by multiplying each factor as 
 derived for the dry coal by 1 the total moisture factor. 
 
OPERATION OF THE PEROXIDE CALORIMETER 97 
 
 EXERCISE VI. 
 
 Calorific Value: If the amount of moisture in the air-dried coal 
 is less than two per cent, no drying in the oven is necessary for the 
 determination of calorific value. One-half gram of air-dried coal is used 
 and the detailed directions should be followed as given below. 
 
 General Arrangement: The Calorimeter should be placed on a 
 good, firm desk in a room where the fluctuations of temperature may be 
 avoided. The general arrangement of parts is shown in Fig. 16. How- 
 
 Fig. 16 
 Calorimeter Using Sodium Peroxide 
 
 ever, it is better to remove the can 5C from the instrument for filling 
 with water. The outside of the can should be dry, and no water should 
 be allowed to spill over into the air spaces of the insulating vessels. 
 
 Exactly two liters of water (preferably distilled) are used, and it 
 should have a temperature of 2 or 3 degrees F. below that of the room. 
 
THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 The thermometer 46 C should extend a little over half way to the bottom 
 of the can. The pulley 37C is connected by a light, flexible cord with a 
 small electric or water motor. Stirring is effected by the spring clips 
 with turbine wings 20AC placed on the bell body. The pulley 37C 
 must be made to revolve at a rather brisk rate. About 150 revolutions 
 per minute, uniformly maintained, will insure a complete equalization 
 of temperature throughout the water. The pulley should turn to the 
 right or as the hands of a watch. 
 
 The Chemical: Sodium Peroxide Na 2 2 : It is absolutely necessary 
 that the chemical employed (sodium peroxide) be kept free from con- 
 tamination. It has special avidity for moisture, and the glass jar with 
 lever fastener, as shown in Fig. 17, has been found best adapted as a con- 
 tainer for this material. The sodium peroxide is furnished in small 
 sealed tins, and the entire contents of a can, upon opening, should be 
 transferred completely to the jar. The half-pound tins will usually be 
 found the most convenient size to use. In any event, the glass jar should 
 be of sufficient size to permit of the complete emptying of the container. 
 
 Fig. 17 
 Container for Sodium Peroxide. 
 
 Commercial sodium peroxide or material that has been much exposed 
 to the air so that any considerable amount of moisture has been absorbed, 
 will give variable and uncertain results. 
 
 The Accelerator: Potassium Chlorate f KCIO S : In order to secure 
 a combustion that shall be uniformly complete, it has been found desir- 
 able to use an accelerator for the purpose of increasing or intensifying 
 the oxidizing effect of the sodium peroxide. While numerous chemicals 
 
THE PEROXIDE BOMB AND CHARGE 
 
 99 
 
 and mixtures have been tried, a very extended experience has made it 
 evident that potassium chlorate is best adapted for this purpose. The 
 amount needed for each charge is weighed out in the same manner as 
 for coal. One gram is the weight taken for fuel of all types. 
 
 Making Up the Charge: See that the 
 floating bottom 4AC is in place at the lower 
 end of the bell body as shown in Fig. 18. The 
 inner surfaces should be dry so that the 
 fusion cup, when put in place, will be sur- 
 rounded by an air space with no film of wa- 
 ter present. The fusion cup also should be 
 thoroughly dry inside before adding the 
 charge. It is well to dry it over a radiator 
 or hot plate, though it should, of course, be 
 cooled for filling. Add to the fusion cup, not 
 assembled, one full measure of sodium per- 
 oxide. In filling the measure with peroxide, 
 it should be tapped against the side of the 
 glass jar to insure against the formation of 
 air pockets which might prevent the complete 
 filling of the measure. The same precaution 
 also as to the dryness of the measure should 
 be observed as for the fusion cup. It should 
 be rinsed thoroughly with tap water after 
 each using and dried by heating over a radia- 
 tor or hot plate. Add one gram of accelera- 
 tor immediately after adding the sodium per- 
 oxide. If the accelerator is lumpy, it is well 
 to rub it smooth in a glass or agate mortar 
 before weighing. Close with the false top 
 Fig. 18 36C, Fig 19, and shake thoroughly until the 
 
 Peroxide Bomb. ingredients are evenly mixed. Add now % 
 
 gram of oven-dry coal. Replace the false top and shake again. When 
 the mixing is complete, tap the holder lightly on the desk to shake all 
 of the material from the upper part of the container, remove the false 
 cap and put in its place the regular cap with stem and ignition wire 
 SAC. To attach the ignition wire, take a single length of fuse wire 7cm. 
 long from the card ; pass one end through the eyelet of one of the term- 
 inals, 24AC, so it will extend beyond the eyelet, sayi/i". Wrap the 
 free wire around the terminal at the narrow portion formed by the 
 notch, giving it three turns, binding in the free end and bending the wire 
 finally downward in line with the terminal. Repeat the same process 
 with the other end of the wire in the other terminal 23 AC. Do not 
 
ioo THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 have the fuse loop too long. It is better not to extend too far into the 
 charge. It will be noticed that the charge fills the crucible at least two- 
 thirds full ; hence, %" extension of the fuse wire below the central term- 
 inal will be ample. 
 
 See that the rubber gasket 27AC is in good shape and that the stem 
 cap seats itself properly. It is to be noted that the gasket seals both 
 the upper edge of the crucible and also the upper edge of the bell body. 
 Marring the edges or rims of any of these parts, therefore, must be 
 carefully avoided. Screw down the cap 5AC firmly in place by use of 
 the two wrenches ; put on the spring clips with the stirring vanes down- 
 ward, leaving the small holes near the lower edge of the bell body 
 uncovered and assemble, as shown in Fig. 16. In assembling, bring 
 the can to its proper place and add 2 liters of distilled water having a 
 temperature 2 or 3 F. below that of the room. In placing the bomb 
 in the water hold it in an inclined position in such a manner that the 
 lower edge of the bell-body will enter the water at an angle and thus 
 avoid entrapping an air pocket under the bottom. 
 
 Ignition: The current required for igniting the charge should be 
 from two to four amperes, and is readily obtained by placing in parallel 
 five 16-candle power lamps in an ordinary lighting circuit of 110 volts. 
 It is well to have the fifth lamp of 32-candle power. Ely this means a 
 suitable current is readily obtained. 
 
 Make a number of preliminary tests by fastening a loop to the term- 
 inals and passing the current without assembling the parts. In this 
 way the behavior of the fuse can be observed. Make a trial with three 
 or four lamps in the circuit. If the wire does not come very quickly 
 to incandescence, increase the resistance until it melts with one or two 
 seconds' delay upon closing the circuit. 
 
 Temperature Readings: The thermometer is inserted so that the 
 lower end of the bulb will be about midway toward the bottom of the 
 can. The pulley should be allowed to revolve a few minutes before read- 
 ing the thermometer, in order to equalize the temperature throughout the 
 apparatus. Take readings one minute apart for two or three intervals 
 before igniting the charge, and continue the same for nine or ten minutes 
 subsequent to ignition. The first three or four readings after ignition 
 are roughtly taken, but after the fourth or fifth minute the temperature 
 should be nearly equalized, and the readings must be carefully taken in 
 order to ascertain the exact maximum and to furnish the necessary data 
 for making a correction for radiation. If the temperature of the water 
 before ignition is one or two degrees below that of the room, the temper- 
 ature at the end of the first minute after ignition will be something above 
 that of the room, and radiation for that period may be considered as 
 self-correcting. Ordinarily, the rise in temperature will continue for 
 
CALCULATIONS AND CORRECTION FACTORS 101 
 
 about four minutes more, at which time the maximum temperature will 
 have been reached. The radiation for this period is found as follows : 
 Read the fall in temperature for each minute for four minutes after the 
 maximum has been reached. The average drop per minute represents 
 the correction to be added to each minute preceding the maximum, except 
 for the minute immediately following ignition. The final temperature 
 thus corrected for radiation, minus the initial reading before ignition, 
 represents the total rise in temperature due to the reaction in the cru- 
 cible. 
 
 Calculations: From the total rise in temperature, corrected for 
 radiation as above indicated, subtract the correction factors for the heat 
 due to the chemical, fuse-wire, etc., as indicated under "Correction 
 Factors" below, and multiply the remainder by 3100. The product will 
 be the number of British thermal units per pound of coal. (See notes 
 (a) and (b) below.) 
 
 It is to be noted that the heat value as derived, refers to the coal in 
 the form in which it is weighed out for making the determination. That 
 is to say, if a coal having 5% of moisture is taken and % gram of the 
 same weighed out and dried in the oven at 212 for 1 hour, then burned 
 in the calorimeter, the result obtained refers to the coal on the basis of 
 5% of moisture and not to the coal as in the oven-dry state. 
 
 To calculate values to "dry coal," divide the number by 100% 
 minus the per cent of moisture present. Thus, a coal having 5% 
 moisture and indicating 11000 B. t. u. would have 11000-=-.95=11579 
 B. t. u. on the "dry coal" basis. 
 
 Note (a), Correction Factors: The method for obtaining the cor- 
 rection for radiation has already been described under Temperature 
 Readings. The other correction components are listed for convenient 
 reference as follows : 
 
 Electric Fuse Wire equals 003C. or .005F. 
 
 Per cent Ash is multiplied by 0025C. or .005F. 
 
 Per cent Sulphur is multiplied by 005C. or .010F. 
 
 1 gram Accelerator equals 150 C. or .270F. 
 
 Hydration Factors: 
 
 For all Bituminous Coals '. 040 C. or .070F. 
 
 For Black Lignites 056C. or .100F. 
 
 Notefb): The factor 3100 is deduced as follows: The water used 
 plus the water equivalent of the metal in the instrument amounts to 
 2123.3 grams. In the reaction 73 per cent of the heat is due to com- 
 bustion of the coal and 27 per cent is due to the heat of combination of 
 CO 2 and H 2 with the chemical. If now % gram of coal causes 2123.3 
 grams of water to rise "r" degrees, and if only 73 per cent of this is 
 due to combustion, then .73X2123.3X2X"r"=rise in temperature which 
 
102 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 would result from combustion of an equal weight (2123.3 grams) of coal. 
 .73X2123.3X2=3100.00. The factor 2 is used instead of the divisor 
 0.5. the weight of coal taken. 
 
 To Dismantle : Remove the thermometer, pulley and cover ; then 
 take out the can and contents entire, so that the lifting out of the 
 cartridge will not drip water into the dry parts of the instrument. 
 Remove the fusion cup and place it on its side in the bottom of a beaker 
 and cover with hot water. After the fused material has dissolved, 
 remove the cup and rinse thoroughly with hot water. Wash the face of 
 the cap and electric terminals thoroughly. For this purpose a jet of 
 hot water or submerging in boiling water is advisable, as the metal is 
 thus left clean and hot, the latter facilitating the drying out of the parts. 
 Place the parts on a radiator or near a hot plate to insure thorough 
 drying. 
 
 Anthracites and Coke: In the case of anthracites and coke, it is 
 well to use 0.2 grams of benzoic acid along with the 1 gram of accelera- 
 tor and y 2 gram of fuel. This substance facilitates ignition as well as 
 the ultimate combustion. The heat resulting from the combustion of 
 this extra 0.2 gram of benzoic acid, which is to be corrected for along 
 with the other correction components, is 1.550 F. 
 
 EXERCISE VII. ' 
 
 For Petroleum Oils: The amount of oil used for a charge should 
 not exceed about % gram; from 0.20 to 0.25 gram giving the proper 
 combustion. The weight of oil is best obtained by means of a small light 
 15 c. c. weighing flask provided with perforated cork and dropping tube 
 with common rubber bulb-cap. Weigh the flask and contents, and by 
 means of the dropping tube discharge 20 to 30 drops of oil and re-weigh, 
 thus obtaining the weight of oil taken by difference. Determine, by 
 experiment, the height in the dropping tube required for the approx- 
 imate amount of oil desired so as to avoid trial weighings. One full 
 measure of chemical (sodium peroxide) and 1 gram of accelerator are 
 first added and thoroughly shaken as already indicated. Also, to facili- 
 tate the ignition of all oils and at the same time promote the ultimate 
 combustion, it is recommended that a small amount (0.2 gram) of ben- 
 zoic acid be used as described under "Anthracites and Coke." Add 
 the oil and benzoic acid last and mix thoroughly by shaking as already 
 indicated and complete the process exactly as for coal. 
 
 Compute by means of the formula as follows : 
 
 Correcting as under coals for radiation, accelerator, benzoic acid 
 and fuse-wire, and letting "r" represent the rise in temperature; then 
 
 "r"X0.73X2123.3 
 
 - =B. T. U. per pound of oil. 
 Wt. of oil 
 
HEAT VALUE OF GASOLINE 
 
 103 
 
 Fig. 19 
 
 EXERCISE VIII. 
 
 Gasolene, Etc.: For gasolene, benzine and very volatile liquids, 
 the difficulty of securing an accurate weight of the material taken is met 
 by the following procedure: By the use of very 
 thin-walled glass tubing of about 5/32 inch in 
 diameter, a light bulb with capillary tip may be 
 blown of approximately the size and shape shown 
 herewith, Fig. 19. After a little practice it is not 
 difficult to blow such bulbs to weigh less than 0.2 
 gram. These may be also made from a capillary 
 obtained by softening an ordinary piece of tubing 
 
 in the flame, and drawing out the same to a filament about the size of 
 a knitting needle. By fusing the end of such filament, bulbs of the 
 desired size and weight may be blown. When so blown, they may be 
 used as follows: Weigh the bulb carefully, then dipping the capillary 
 end into the liquid and alternately warming gently and cooling the bulb 
 a quantity of gasolene is drawn into the bulb. When about 0.2 gram 
 is obtained, seal the capillary in the flame and weigh accurately. Add 
 the sodium peroxide and accelerator to the fusion cup first and thor- 
 oughly mix by shaking in the usual manner. Next add 0.2 gram of 
 benzoic acid and the bulb of gasoline. Put on the ignition top and clamp 
 firmly in place w T ith the screw cap. Rotate the bomb and bring it into an 
 inverted position, shaking lightly at first to bring the bulb on top of the 
 chemical and nearest the bottom of the fusion cup. Thus inverted 
 shake the bomb vigorously to break the bulb, then assemble in the 
 calorimeter in the usual manner. In calculating, a correction is neces- 
 sary, in addition to those normally observed, on account of the heat of 
 fusion due to the glass present. This amounts to 0.03 F. for each 0.1 
 gram of glass used in the bulb. This should be subtracted along with 
 the correction for accelerator and fuse-wire. The corrected rise, "r," 
 is then used in the formula as above given for petroleums. 
 
 EXERCISE IX. 
 
 Sulphur: Where determinations for sul- 
 phur are to be made independently of the cal- 
 orimetric process, a special apparatus as shown 
 in Fig. 20 is employed. The charge consists of 
 one measure of sodium peroxide and y 2 gram 
 of coal. Close with the cover and screw cap and 
 shake thoroughly. Ignite the charge by apply- 
 ing the flame of a Bunsen burner to the bottom 
 of the fusion cup for a moment. Remove the 
 flame as soon as the reaction has commenced, 
 which will be indicated by the lower portion of 
 
 300 
 
 Fig. 20 
 
104 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 the cup betcoming a dull red. After the charge has ignited, the bomb 
 may be cooled without delay by holding under the tap or submerging 
 in water. If the cover is fitted with a rubber gasket, the cooling with 
 water should follow very soon after the ignition. If an asbestos gasket 
 is used, the cooling may be attended to at leisure. The use of a rubber 
 gasket is preferred, as it does not disintegrate on washing. The dis- 
 mantling and dissolving out the fusion from the cup is carried out in 
 
 Fig. 21. Sulphur Photometer. 
 
 the usual manner as already described. The solution is neutralized 
 with chemically pure hydrochloric acid and 1 c. c. of the concentrated 
 (1.19 sp. g.) acid added in excess. The bulk of the solution should be 
 about 300 c. c. From this point the sulphur as S0 3 is determined in 
 the regular manner, either by the gravimetric or photometric process. 
 The Photometric Process: Transfer the slightly acid solution to 
 the 250 c. c. flask and make up to the mark. Mix thoroughly and meas- 
 ure out for analysis 50 c. c. of the solution into the cylinder G, Fig. 21, 
 and 50 c. c. of distilled water so that the final volume shall be 100 c. c. 
 
THE PHOTOMETRIC DETERMINATION OF SULPHUR 105 
 
 Transfer the 100 c. c. of solution from the cylinder to the Erlenmeyer 
 flask E, add 0.3 to 0.5 gram of Special Barium Chloride Powder,* and 
 without delay close the flask with the cork and shake vigorously for one 
 or two minutes, then allow to stand at room temperature, with occasional 
 shaking, for 15 to 20 minutes. 
 
 In reading the turbidity, the solution is shaken and a portion 
 poured from the Erlenmeyer flask, E, into the wide mouthed dropping 
 funnel, F. The graduated tube, A, is adjusted in the dark tube so that 
 the rounded lower end dips well into the water in the flat bottomed dish, 
 B, which should be about y 2 inch in depth. Adjust the flame to a height 
 of 1 inch. This is accomplished by having the tip appear about % of 
 an inch above the edge of the metal chimney.** 
 
 By means of the pinch cock admit the turbid solution until the point 
 of light from the candle flame, L, just disappears, the last point of light 
 from the flame being no longer visible. Do not take account of the 
 slightly luminous center that appears when the amount of sulphur is 
 high and the readings are on the lower portion of the scale, say from 40 
 to 60 mm. Take as the end point the disappearance of the point of light. 
 Remove the tube and read in milligrams the depth of the liquid. By 
 means of the table or curve is shown the weight in milligrams of the 
 sulphur present in the 100 c. c. of solution. If 50 c. c. were taken from 
 the 250 c. c. flask, and this latter contained the fusion from a y 2 gram 
 sample of coal, then the sulphur reading would be the weight present in 
 1/10 gram of coal. By removal of the decimal point, therefore, one place 
 to the right, there would be shown the weight of sulphur in one gram, of 
 coal which can then be read in parts per 100, or per cent, by placing the 
 decimal two more places to the right. If read in milligrams each unit 
 is then 1 per cent. 
 
 For example, if the results show a depth of 105 millimeters, there 
 would be indicated 1.93 milligrams of sulphur present in the quantity 
 taken, that is 0.00193 grams. Now, if % of the % gram of coal is repre- 
 sented in this amount, the reading is for 1/10 gram of coal. For 1 gram 
 of coal there would then be 0.0193 gram of sulphur, or 1.93per cent. 
 
 If the sulphur is so great in amount as to afford too great turbidity 
 for satisfactory reading, repeat the process, measuring out 25 c. c. of 
 the solution and diluting with water sufficient to make a total of 100 
 c. c. in volume, and proceed as above outlined. After multiplying the 
 
 *The Special Barium Chloride Powder is composed of equal parts of Barium 
 Chloride (BaCl 2 ) and Oxalic Acid (H^O*). By trial measurement on the point 
 of a spatula and weighing a few times, the amount of powder by bulk can be 
 readily determined with sufficient accuracy. 
 
 **A small 3-volt tungsten bulb with current from 2 dry cells gives a more 
 satisfactory light. The readings check with those obtained with the gas flame 
 so that the same curve may be used. 
 
106 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 weight of the sulphur thus indicated by 2, the conditions will be the 
 same as indicated in the paragraph above. 
 
 In cases where the content of sulphur in the coal is so low that the 
 reading on the tube comes above the limit of graduation, a larger 
 quantity of the solution representing a greater amount of coal should 
 be taken. Thus, if we take 100 c. c. of the solution, we will be taking 1 
 % of % gram of the original coal or % (.2) gram of coal. Now, the 
 sulphur indicated on the curve will be the weight in milligrams which 
 accompanies 0.20 gram of coal. If, therefore, we read the percentage 
 as normally indicated and divide by 2; we will have the correct indica- 
 tion for the content of sulphur. For example, if the reading under these 
 conditions shows a depth of 105 m. m. there would be indicated 1.93 
 milligrams of sulphur for the amount of coal taken, 0.2 grams. This 
 would be 0.965 milligrams for 0.20 gram of coal, or 0.96 per cent.* 
 
 Special care must be taken to prevent the settling out of the pre- 
 cipitate. A reading can be quickly made and the contents of the tube 
 poured back into the funnel. Readings should be repeated several times, 
 thus keeping the mixture stirred and affording greater accuracy as to 
 the final average taken. Before beginning, the bottom of the tube inside 
 should be cleansed by means of a swab to insure that no film of pre- 
 cipitate from the previous test has settled out. 
 
 The diaphragm between the dark cell and the candle prevents 
 moisture from forming on the bottom of the water cup. Notice should 
 be taken, however, as to this point; and, in case of a film of moisture 
 forming, it may be prevented by warming the water used in the cub a 
 little above the room temperature. For the same reason be sure that no 
 sediment has settled out on the bottom of the cup, B. Perfect alignment 
 of the flame through the diaphragm and tube should be secured. The 
 conditions as to strength of light, methods of reading, the end point, etc., 
 may vary from the standards adopted in the table. Each individual 
 may easily check his own method by making up a solution of chemically 
 pure sulphuric acid, having 0.5438 gram per liter, which is equivalent 
 to 0.0001 gram of sulphur per c. c. Use 15 or 20 c. c. in making the test. 
 
 Note: In tabulating the results of coal analysis remember that the 
 constituent percentages in the case of each condition of reference should 
 total 100 per cent; this also excluding the factor for sulphur, which in 
 the process of proximate analysis is a constitutent part of certain com- 
 ponents, approximately % going with the volatile matter and % remain- 
 ing with the coke. 
 
 *Some coals, especially of the semibituminous or Pocahontas type, have a 
 content of sulphur so low as to make it advisable in such cases to dissolve the 
 fusion in a smaller quantity of water, so that the volume when made up shall be 
 100 c.c. With sulphur so low as 0.5 per cent the entire solution would be required 
 for use with the photometer. 
 
CHART FOR SULPHUR READINGS 
 
 107 
 
 53 52 3.1 3.0 ~2.<? 2.8 2.7 2.6 2.5 2.4 23 2.2 
 
 2.0 Ifl 1.8 L7 J.6 15 1.4 
 
 MILLIGRAMS OF SULPHUR 
 
 Fig. 22. Curve showing the weight of sulphur in milligrams 
 
 1.2 
 
io8 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 Fig. 23 
 Oxygen Bomb 
 
 EXERCISE X. 
 
 Heat Values ly the Oxygen Bomb Calorimeter: Figure 23 shows 
 the arrangement of the parts of the bomb when ready for placing in the 
 calorimeter. When the calorimeter is dismantled the double cover to 
 the insulating chamber is supported on a ring-stand as shown in the cut, 
 Fig. 2, Part I. This affords a convenient method of handling the stirring 
 device and insures greater safety for the thermometer. 
 
MANIPULATION OF THE OXYGEN BOMB 
 
 109 
 
 When the bomb is opened and made ready to receive the charge of 
 fuel, the cap is most conveniently held on the ring-stand which accom- 
 panies the instrument. Thus supported, the fuel capsule and fuse wire 
 are readily adjusted as shown in Fig. 24. For coal, one gram of the 
 
 Fig. 24 
 Holders for Filling and Adjusting the Fuse Wire. 
 
 air-dry sample, ground to pass a 60 mesh sieve, is weighed in the capsule 
 43 A, Fig. 23. Attach the ignition wire to the terminals, 4 A and 5 A, by 
 passing one end thru the eyelet of one of the terminals so it will extend 
 beyond the eyelet about *4- inch. Wrap the free wire around the term- 
 inal at the narrow portion formed by the notch, giving it three turns, 
 binding in the free end and bending the wire finally downward in line 
 with the terminal. Repeat the same process with the other end of the 
 wire. The fuse wire should be about 7 cm. long. That part of the 
 wire between the terminals should be bent into a somewhat narrow U 
 shaped loop so that the fuse wire will not touch the sides of the capsule. 
 Adjust the wire so that the lower part of the fuse loop will just touch the 
 surface of the coal. 
 
no THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 Transfer the cover to the bomb, in which a half cubic centimeter of 
 water has been placed for taking up the acids formed in the process of 
 combustion. The bomb should rest in the octagon holder for filling. 
 Screw on the cap, 3A. In sealing, apply the large wrench, using good, 
 firm pressure, though only moderate force is necessary for securing a 
 perfect seal at the rubber gasket, 54 A. 
 
 For filling with oxygen, connection is made with the flexible copper 
 tubing and oxygen is admitted until a pressure of 25 30 atmospheres 
 is indicated. In admitting the oxygen the needle valve next to the pres- 
 sure gauge is opened slightly to avoid a sudden rush of gas. After a 
 sufficient amount has been admitted, close the needle-valve and open 
 the pet-cock below the gauge in order to release the oxygen under pres- 
 sure in the tube and connections. The check valve, 11A Fig. 23, auto- 
 matically closes and retains the oxygen at the desired pressure. 
 
 Transfer the bomb carefully, without jarring, to the oval can which 
 has been placed in position in the calorimeter. The long axis of the oval 
 should be in line with the operator, that is, at right angles to the work 
 desk. The pointer, 57A Fig. 25, and a notch in the can directly oppo- 
 site, serve as guides for correctly locating the vessel. The circular eleva- 
 tion in the bottom which directs the locating of the bomb should be 
 toward the operator. Turn the bomb so that one of the faces of the 
 octagon, rather than an angle, will be toward the operator, thus giving 
 more room for the thermometer. Make the connection with the electric 
 terminal, 58A, and add 2000grams of water, preferably distilled. The 
 temperature of the water should be 2 or 3 Fahrenheit below that of 
 the room. 
 
 In placing the cover on the calorimeter have the thermometer 
 toward the operator. This will bring the pulley with turbine stirrer at 
 the back of the instrument. Bring the cover to place carefully so as to 
 avoid striking the thermometer against the metal parts (see Fig. 25). 
 Seat the spring clips for holding the cover firmly in place and connect 
 the pulley with the motor. The motor is adjusted so as to give the tur- 
 bine pulley a speed of about 150 revolutions per minute turning to the 
 right or clockwise. A uniform speed throughout a determination is 
 desirable. 
 
 By use of the telescopic lens, readings of the thermometer for the 
 preliminary period are taken at one minute intervals for five minutes. 
 At the fifth reading close the electric circuit for a second or not to exceed 
 two seconds. Ignition of the sample should be indicated by a rise of the 
 mercury, which becomes rapid after 20 or 30 seconds. The combustion 
 period extends over 5 or 6 minutes and terminates when the maximum 
 temperature has been reached, or when the rate of change has become 
 uniform. The final period follows the combustion period. Eeadings are 
 taken at minute intervals for five minutes. 
 
RADIATION CORRECTIONS AND COMPUTATIONS in 
 
 OBSERVATIONS* 
 
 During the ignition period, if the temperature rise for the sample 
 in hand is not approximately known, take thermometer readings at 40, 
 50 and 60 seconds after firing. 
 
 Make the following notations : 
 
 (1) The rate of rise (r) for the preliminary period in degrees per minute. 
 
 (2) The time (a) at which the last reading of the preliminary period is made, 
 immediately before firing. 
 
 (3) The time (b) when the rise of temperature has reached six-tenths of its 
 total amount. This point can generally be determined by adding to the tem- 
 perature reading at the time of firing 60 per cent of the expected temperature 
 rise and noting the time (b) when this point is reached. If the approximate 
 temperature rise is not known, six-tenths of the total rise as subsequently 
 developed, when added to the temperature reading at (a), will indicate the 
 time (b) by interpolating readings obtained at the 50, 60, and 70 second 
 periods after firing. 
 
 (4) The time (c) when the maximum temperature has been reached, or when 
 the rate of change has become uniform, usually about five minutes after firing. 
 
 (5) The rate of change (r 2 ) for the final period in degrees per minute. 
 
 COMPUTATIONS 
 
 Apply the corrections as indicated on the thermometer certificate 
 for the initial (a) and final (c) readings. 
 
 Multiply the rate (r x ) by the time (b a) in minutes and tenths of 
 a minute and add the product to the corrected temperature reading at 
 time (a). 
 
 Multiply the rate (r,) by the time (c b) and add (or subtract if 
 the temperature was rising during the final period) the product to the 
 corrected temperature reading at time (c). 
 
 The difference of the two readings thus modified to account for radi- 
 ation corrections gives the total rise of temperature due to combustion. 
 
 Multiply the total rise thus found by the water equivalent of the 
 calorimeter, the product giving the total amount of heat liberated. If 
 the thermometer readings were in Fahrenheit degrees the product gives 
 the heat value in B. t. u. 
 
 *See report of Committee on Methods of Coal Analysis, Journal of Industrial 
 and Engineering Chemistry, Vol. 5, p. 517 (1913). 
 
ii2 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC 
 
 CORRECTIONS 
 
 The heat produced by the formation of nitric acid from the nitro- 
 gen in the oxygen and sulphuric acid from the sulphur in the combust i- 
 
 Fig. 25 
 Oxygen Bomb Calorimeter 
 
 ble is corrected for by washing the bomb thoroughly with distilled water 
 after the determination is completed and titrating the washings with a 
 solution of sodium carbonate. 
 
CORRECTIONS 113 
 
 Make up the sodium carbonate solution by dissolving 2.061 grains 
 chemically pure Na 2 C0 3 in one liter of distilled water. One cc=l 
 B. t. u. for the formation of nitric acid. 
 
 The sulphuric acid formed has produced an equivalent of heat in 
 excess of the correction applied as for nitric acid equal to 9 times the 
 sulphur content expressed in per cent. 
 
 Iron wire of No. 34 American Gauge produces heat at the rate of 
 4 1/2 B. t. u. for each centimeter of wire burned. A correction should, 
 therefore, be made for the length of wire actually consumed. Subtract 
 the unburned portion remaining on the terminals from the original 
 length in centimeters and multiply the remainder by 4 1/2, the result is 
 the correction in B. t. u. for the wire consumed. 
 
 Finally note that the total indicated heat as corrected for nitric 
 acid, sulphuric acid and fuse wire refers to a quantity of fuel repre- 
 sented by the weight of the charge taken. If this weight were exactly 1 
 gram no further computation is necessary. If the weight taken varied 
 from an even gram, the indicated B. t. u. as above derived must be 
 divided by the weight of fuel taken. 
 
 To discharge the oxygen from the bomb, press down the valve, 13A, 
 with the thumb to release the gas. Do not try to remove the screw cap, 
 3A, until after the gas pressure has been released. 
 
 Upon opening examine the interior for unburned carbon. If any 
 is found reject the experiment. 
 
 To standardize the instrument, make a combustion using a stand- 
 ard substance of known heat value as pure benzoic acid. Add to the ac- 
 cepted heat value of the quantity taken, say 1. gram, the heat due to the 
 combustion of the wire and the nitric acid formed. Divide the heat 
 value thus represented by the temperature rise, corrected in the usual 
 manner. The quotient represents the total water equivalent made up 
 to the actual grams of water employed, 2000 plus the equivalent in water 
 of the metal parts, etc., of the apparatus. 
 
ii4 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 EXAMPLE OF COMPUTATIONS 
 Lab. No. 7968 
 Weight of material burned .8 grams 
 
 Date June 29, 1914 
 Room Temp. 23.7 C. 
 
 Sulphur in coal 4.31% 
 
 Time Temperature 
 2-1 1 295 
 
 12 299 
 
 13 303 
 
 14 307 
 
 15 310 
 
 (a) 16 313 
 
 Fired 
 
 (b) 17-12 1.573* 
 
 O of Beckman Ther. 2i.8C. 
 Water Eqv. 2416 gram. 
 
 .018 
 
 5 
 
 >ri = - = 0.0036 
 
 Initial temp. 
 Certif. Corr. 
 Corr. initial 
 
 0.313 
 .001 
 
 .312 
 
 Final 
 Corr. 
 Final 
 
 2.399 
 
 .009 
 
 2.408 
 
 r 2 = 
 
 .005 
 S 
 
 = O.OOI 
 
 21 2.399 
 
 22 2.398 
 
 23 2.397 
 
 24 2.397 
 
 25 2.395 
 
 26 2.394 
 
 (b - a) X n = 1. 12 X .0036 0.004 
 
 (c - b) X r 2 = 3.48 X .001 
 
 .0.003 
 
 316 
 
 2.411 
 .316 
 
 Setting Corr. 
 Stem 
 Corrected rise. 
 
 2.095 
 
 O.OOI 
 O.OOI 
 
 Total Calories 2416 X 2.097 = 5066.4 
 Acidity titration = 27.2 Cal. 
 Corr. for wire = 18.4 " 
 Sulphur Corr. =44.8 " 90.4 
 
 .2.097 
 
 Calories from .8 gram = 4976. 
 Calories per gram = 6620. 
 
 *The initial temperature is 0.313 
 60% of the expected rise is 1.260 
 
 The time to observe then is 1.573 
 
 Note a: For anthracite coal a thin pad of asbestos felt should be formed on 
 the inside of the capsule. Take a small amount of asbestos pulp, squeeze out the 
 water and form a felt on the bottom and sides of the capsule, then dry and ignite. 
 This will prevent the lowering of the temperature below the ignition point before 
 combustion is complete. 
 
ULTIMATE ANALYSIS 
 
 Note b: To insure against loss of oxygen thru leakage it is well to keep 
 the needle-valve between the gauge and the oxygen cylinder and also the valve on 
 top of the cylinder closed when not drawing out oxygen. For filling the bomb, 
 open f.rst the cylinder valve slightly, then open the needle-valve gradually, regulat- 
 ing the flow by noting the gauge indicator. 
 
 Note c: Do not attempt to displace the air in the bomb with oxygen before 
 filling. A certain amount of nitrogen is necessary for the complete oxidation of 
 the sulphur. (See Vol. 6., p, 812, Journal of Industrial and Engineering Chemistry). 
 
 CHAPTER VIII 
 ULTIMATE ANALYSIS OF COAL 
 
 Total Carbon Determination: The percentage of total carbon in 
 the coal used is a necessary factor in determining the heat losses in the 
 
 / 
 
 FIG. 26 
 
 flue gases as already indicated in the calculations on pages 73 to 76 
 inclusive. This value may be obtained by making an ultimate analysis 
 
ii6 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 which consists essentially in burning a sample of the coal in a current 
 of oxygen, absorbing the C0 2 formed in a solution of potassium hydrox- 
 ide, and obtaining the amount of C0 2 formed by direct weighing. A 
 more convenient method makes use of the fusion resulting from the 
 calorimetric determination using sodium peroxide. As a result of the 
 reaction, all of the carbon of the coal is present in the fusion as sodium 
 carbonate, Na 2 C0 3 . By treating with acid, therefore, in a suitable appa- 
 ratus, the C0 2 is delivered in a form to be measured by volume as shown 
 in Fig. 26. 
 
 The apparatus should be located on a laboratory desk or table 
 where an even temperature can be maintained. 
 
 Fill the jacketing tube "J" with water slightly acidulated to keep 
 it clear. Fill the leveling tube "L" with Avater that has had two or 
 three c.c. of sulphuric acid added. A few drops of methyl-orange in the 
 leveling tube will impart a color to the water, greatly facilitating the 
 readings. 
 
 Connect the inlet "D" with air pressure and adjust so that two or 
 three bubbles of air per second will enter the jacketing water. This is 
 for the purpose of keeping the temperature of the water equalized 
 throughout a determination. By reading the thermometer hung in the 
 water the temperature of the gas under observation is obtained. 
 
 The operation is as follows : The large double pipette " P " is half 
 filled with 40 per cent solution of caustic potash, or such as is ordinarily 
 used for the absorption of C0 2 gas. By turning the three-way cock "T" 
 to connect with the pipette "P" and lowering the leveling tube "L" 
 the liquid in "P" is brought into the right hand bulb and made to rise 
 in the capillary tube to the mark on the right limb of the capillary. 
 The three-way cock is now closed to the pipette bulb and opened to the 
 tube running to the flask "B". By raising the leveling tube "L" the 
 liquid in the burette "G" is made to rise to the three-way cock "T", 
 thus completely filling the burette. The three-way cock is now closed 
 to retain the liquid in the burette at the zero point, till evolution of the 
 gas is begun. 
 
 The cup containing the fused material from a calorimetric determi- 
 nation is placed on its side in the bottom of a small beaker and covered 
 with hot water that has been boiling for 5 or 10 minutes. When the 
 fusion is dissolved remove the cup, rinsing it well, and pour the solution 
 directly into the flask "B". Wash out the beaker thoroughly with hot 
 water and pour the washings in with the main portion. Connect with 
 the funnel tube ''A" and bring the ring support with wire gauze in 
 place under the flask. Open the stop cock at the lower end of the funnel 
 and boil the contents of the flask for 3 or 4 minutes. Remove the flame 
 and at once close the funnel cock. In this way the oxygen from the 
 
DETERMINATION OF TOTAL CARBON 117 
 
 sodium peroxide will be driven off together with the air in the flask. 
 Also, since the three-way cock "T" is closed there will be a partial 
 vacuum in the flask. 
 
 With the cock to the funnel tube "A" closed, enough acid is added 
 to "A" to completely neutralize the alkaline solution in "B" and leave 
 a distinct excess of acid. Either hydrochloric or sulphuric acid may be 
 used. Thirty cubic centimeters of concentrated hydrochloric acid, or 
 15 c.c. of a solution of concentrated sulphuric acid and water in the 
 proportion of 1 :1 will be found sufficient. 
 
 To operate, lower the leveling tube "L", open the three-way cock 
 "T" to the tube connecting with the flask "B" and admit acid drop 
 by drop from the funnel "A". Meantime the circulating water for the 
 condenser "C" should be turned on. 
 
 When the evolution of gas has about reached the capacity of the 
 graduated burette "G", the acid is shut off, the three-way cock "T" 
 closed and a reading of the volume of the gas carefully taken by bringing 
 the two surfaces of liquid in the leveling tube and burette exactly on a 
 level. Read also the temperature of the jacketing water and note the 
 barometric pressure. The cock " T " is now opened to the capillary and 
 the gas volume forced completely over into the bulb "P" where it is 
 held by closing the cock "T". Here it is left for complete absorption 
 of the C0 2 . The cock "T" may be again opened to connect with the 
 flask "B", the liquid in the burette "G" being at the zero point as 
 before. The apparatus is now ready for a second evolution and meas- 
 urement of a gas volume. 
 
 A second reading is similarly taken and the volume driven over into 
 "P" as before, along with the former volume. 
 
 Finally heat is added to the flask "B" and after a few minutes 
 boiling, hot water is added through the funnel "A", until the entire 
 space in "B" to the three-way cock "T" is filled. The flame of course 
 being removed. 
 
 The various readings should be so adjusted that this final process 
 will produce a volume sufficiently large to bring the same down upon 
 the graduated portion of the burette for reading. 
 
 Finally the residual gas in "P", after the complete absorption of 
 the C0 2 , is returned to the burette "G" and the volume read. The dif- 
 ference between this volume and the total of the several volumes is the 
 total carbon dioxide present in the fusion. 
 
 By referring to Table XIX there is found at the observed tempera- 
 ture and pressure the weight in milligrams of carbon in one cubic centi- 
 meter of C0 2 gas.* Multiply this weight by the number of cubic centi- 
 
 *See also "The Weight of Carbon Dioxide with a Table of Calculated 
 Values." S. W. Parr, Journal American Chemical Society, Vol. XXI, p. 237, 1909. 
 
ii8 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 TABLE XIX 
 
 CM 
 
 O 
 
 u. 
 o 
 
 o 
 
 CD 
 
 a 
 
 u 
 
 I CO * 
 
 2 < 5 
 
 Sg ? 
 
 OJ 
 
 rO 
 
 ro 
 
 in 
 
 in 
 
 
 cr> 
 
 r- oo 
 
 t 
 
 S. 
 
 
 f 
 
 CVJ 
 
 f\ 
 
 CO 
 CVJ (\J 
 
 
TOTAL HYDROGEN 119 
 
 meters obtained in the above operation and the product equals the 
 weight in milligrams of pure carbon. From this should be subtracted 
 the weight of carbon found by running a blank in exactly the same 
 manner, using one measure of the sodium peroxide instead of the fusion. 
 
 After subtracting the blank, the carbon remaining represents the 
 total carbon present in the fuel. Divide this number by the weight of 
 fuel taken and multiply by 100. The product is the per cent of carbon 
 present in the sample taken. 
 
 Xote: The fusion and alkaline solution should be covered and kept free 
 from circulating air, so as to avoid absorption of CO.. 
 
 Hydrogen: In the calculations for deriving a heat balance, the 
 engineer requires the factor for the total hydrogen in the coal used. 
 The hydrogen present is considered as combined in two different ways. 
 In one, the hydrogen is "disposable" or "available" for combustion. 
 In the other it is supposed to be joined with oxygen to form H 2 and 
 when thus combined is not available for the production of heat. The 
 available hydrogen may be derived as follows : If we let C represent 
 the percentage of total carbon, then 14544C will equal the heat value 
 for that constituent. To this add the heat value of the sulphur present, 
 4500S. The remainder of the heat is due to the combustion of hydrogen. 
 Hence, with a value for hydrogen of 62,100 the percentage of available 
 hydrogen, H, will be represented by the expression : 
 
 H B.t.u - - (14544C + 4500S; 
 
 62,000 
 
 The hydrogen not available or considered to be in combination with 
 oxygen is estimated as % of the oxygen or 0/8 as in Dulong's formula. 
 There is required, therefore, the percentage of oxygen and this is deter- 
 mined by difference. That is, if we subtract from 100 the values for 
 ash, sulphur, total carbon, available hydrogen, and nitrogen, the differ- 
 ence will be the non-available hydrogen and oxygen present in the ratio 
 of H 2 : 0. Hence 1/9 of this difference is H 2 and 8/9 is the oxygen 
 percentage. That is, the per cent of chemically combined water is rep- 
 resented by the formula : 
 
 H 2 = 100 ( A + S + C + available H + N) 
 
 The only undetermined factor in the above expression is that for 
 nitrogen. It may be determined directly by the Kjeldahl method, or, 
 for purposes of calculating a heat balance it is quite sufficiently accurate 
 to assume a value of 1 per cent for nitrogen, since the amount present 
 in bituminous coals varies only within relatively narrow limits, say from 
 0.75 to 1.50 per cent. 
 
CHAPTER IX 
 THE ANALYSIS OF FLUE GASES 
 
 Reagents: The analyses to be made in this course will be performed 
 with what is known as the "Orsat apparatus." This is made of a jack- 
 eted 100 c.c. gas burette and leveling bottle permanently connected by a 
 capillary tube having four side arms to three pipettes and to the open 
 air. The end of the capillary tube extends outside the case for conven- 
 ience in taking a sample of gas. The pipettes are provided with re- 
 agents, as follows : 
 
 1. Potassium Hydroxide, for absorption of carbon dioxide, C0 2 . 
 Strength of solution, 50%. One c.c. absorbs 40 c.c. of carbon dioxide. 
 
 2. Potassium Pyrogallate, for absorption of oxygen, 2 . Dissolve 
 5 grams of pyrogallic acid in 20 c.c. of water and pour into the proper 
 pipette. Next dissolve 120 grams (approximately) of potassium hy- 
 droxide (KOH), in 80 c.c. of water and add to the same pipette. Keep 
 protected from the air. One c.c. absorbs 2 c.c. of oxygen. 
 
 3. Cuprous Chloride, for absorption of carbon monoxide, CO. 
 This may be prepared in two ways : ( 1 ) by keeping a bottle full of hy- 
 drochloric acid (1.10 sp. gr.) having copper oxide in the bottom and 
 much copper wire in it, or, (2) shake together in a closed flask 200 
 grams commercial cuprous chloride and a solution containing 250 grams 
 ammonium chloride in 750 c.c. of water. Add enough ammonium hy- 
 droxide to bring the cuprous chloride completely into solution. This 
 will require about 1 volume of ammonium hydroxide solution ,sp. gr. 
 0.90) to 4 volumes of the solution. Keep protected from air in a bottle, 
 which has suspended in it a spiral of copper extending from top to bot- 
 tom of the bottle. 1 c.c. of this solution will absorb 16 c.c. carbon mon- 
 oxide, but it is best to renew the solution after it has absorbed its own 
 volume of carbon monoxide, since the compound formed readily disso- 
 ciates in concentrated solution, giving off gaseous carbon monoxide. 
 
 These solutions may be protected from the air by covering the sur- 
 face in the outside arm of the pipette with a layer of kerosene. Great 
 car must be exercised, however, to keep the kerosene out of the absorp- 
 tion bulb of the pipette, otherwise the kerosene vapors will increase the 
 volume of the gas residue, and thus spoil the determination. 
 
 EXERCISE I. 
 
 Analysis of Atmospheric Air: Adjust the reagent in each pipette 
 by drawing the solution up into the capillary tube to the mark just be- 
 low the rubber connection. Fill the jacketed measuring burette with 
 water out to the end of the capillary tube, then draw in a little over 100 
 
 120 
 
ANALYSIS OF AIR 121 
 
 c.c. of air by opening the outer vent and lowering the leveling bottle. 
 Next, slowly raise the leveling bottle until the meniscus gives a reading 
 of exactly zero, and the level of the water in the burette is just equal to 
 that in the leveling bottle. 
 
 Oxygen: Close the pinch cocks on all vents and open the one on 
 the second pipette, the one containing potassium pyrogallate ; now raise 
 the leveling tube slowly, thus forcing the air into the pipette. When 
 the water has reached the 100 c.c. mark on the burette, shut the pinch 
 cock and allow to stand for five minutes. Now open the cock and run 
 the gas back into the burette by lowering the leveling bottle. "Watch 
 the surface of the pyrogallate solution, and as it approaches the mark 
 slow up the flow of gas by careful manipulation of the leveling bottle 
 the solution can be brought just to the mark and then shut off, giving 
 much more delicate adjustment than can be obtained by manipulation 
 of the pinch cock alone. It is very important that none of these solu- 
 tions get above the pinch cock, as the potassium hydroxide in them in- 
 terferes with the carbon dioxide determinations in subsequent samples. 
 
 Repeat the absorption for 3 minutes and read again. The contrac- 
 tion in volume is due to absorption of oxygen. Calculate the percentage 
 on the sample taken. 
 
 EXERCISE II. 
 
 Respired Air: The apparatus should be in adjustment after the 
 preceding experiment. Take a long breath and hold in the lungs for 
 some time, then blow it into one of the rubber balloons. Attach this to 
 the outer vent of the apparatus and draw in a sample of 110 c.c. as be- 
 fore. Now close this pinch cock and open the one at right angle, to the 
 air; then, by raising the leveling bottle slowly, bring the surface of the 
 water to the zero mark and close the cork opening to the air. 
 
 A. Carbon dioxide. Always absorb the carbon dioxide first 
 bringing the gas into the first or potassium hydroxide pipette. Allow it 
 to stand for 5 minutes and repeat for 3 mintues. The contraction is due 
 to carbon dioxide determine its percentage. 
 
 B. Oxygen. Determine oxygen as in the case of atmospheric air. 
 The difference between the total contraction and the first one is due to 
 oxygen. Compute the percentage. 
 
 C. Nitrogen. This is determined by difference. 
 
 100 o/o (o/o C0 2 + o/o 2 ) = o/o N 2 
 
 EXERCISE III. 
 
 Flue Gas: All determinations of the constituents of flue gas are 
 carried out as described in Exercise II. 
 
 Carbon Monoxide is determined after oxygen by means of the third 
 
122 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC 
 
 pipette, allowing the gas to stand for 8 minutes. In calculating nitro- 
 gen this is of course taken into consideration. 
 
 Analyze one sample of atmospheric air, two samples of respired 
 air and two of flue gas. 
 
 Record on the blank attached to the Orsat apparatus the volumes 
 of gases absorbed so that the strength of any solution can be determined 
 at any time. 
 
 CHAPTER X 
 
 OIL EXAMINATION 
 
 EXERCISE I. 
 
 Identification as to Origin: Weigh carefully a No. 2 beaker and 
 add 10 gms. of oil, then 75 c.c. of 6 per cent alcoholic potash solution. 
 Evaporate on the water bath, stirring well, until all alcohol is removed. 
 Take up the residue with 50 to 75 c. c. of water and transfer to a sep- 
 aratory f unnel. Add about 75 c.c. of petroleum ether, rinsing the beaker 
 with it and transferring all washings to the funnel. (Keep the ether 
 away from a lamp). 
 
 Shake well and let stand over night. Draw off the lower solution, 
 stopping the flow when the line of separation reaches the top of the stop 
 cock. Add another portion of water, shake up again until any soap that 
 may cling to the funnel is washed off, and allow to settle. Draw off as 
 before, this time getting all the water solution into the beaker. Heat 
 this solution on the water bath for 15-20 minutes, or until the odor of the 
 petroleum ether is gone. Cool and make slightly acid with dilute sul- 
 phuric acid. If there is any soap present it will be decomposed, yield- 
 ing free fatty acids which rise like oil or curd to the top of the solution. 
 "Weigh carefuly about 5 grams of pure white beeswax and add to the 
 beaker, melt the whole and allow to cool. When cold, remove the cake 
 of wax, dry between filter papers, place in desiccator, and weigh in half 
 an hour. The increase in the weight of wax represents the fatty acids 
 from vegetable or animal oils in the sample taken. The amount of oil 
 corresponding to the fatty acid will be represented approximately by 
 multiplying the weight obtained by 1.04. Calculate the percentage of 
 vegetable and animal oils in the original sample. 
 
 Any petroleum oil present will dissolve in the upper layer of ether, 
 imparting a color to it. 
 
 EXERCISE II. 
 
 Specific Gravity: The specific gravity of oils may be taken with 
 a pyknometer or with a specific gravity hydrometer. The oil should be 
 
OIL ANALYSIS 123 
 
 warmed sufficiently to allow free movement of the instrument. The tem- 
 perature must also be read and corrected for. See table 2 of the 
 Appendix. 
 
 Where available, the most accurate method is that of the Westphal 
 balance, where a correction for temperature may also be necessary. Con- 
 sult the Appendix for a table of specific gravities of standard oils. In 
 trying to identify an oil by its specific gravity, however, the analysis 
 under Exercise I must be taken into account, for many mixtures of 
 cheap oils are made to imitate some of the more expensive varieties. 
 
 EXERCISE III. 
 
 Viscocity: This property is often confounded with specific grav- 
 ity. The one is the time taken for a given quantity to flow through an 
 orfice as compared with water, the other is the weight of a given volume 
 as compared with the same volume of water. In the event that a 
 standard viscosimeter is not available, a pipette graduated to deliver 
 100 c.c. of water from the bulb alone in 34 seconds may be used as a 
 standard. 
 
 Take a 100 c.c. pipette, fill with water and note the time required 
 for the water to empty from the ~bulb alone. Repeat once. Now fill to 
 the top of the bulb with oil and empty in exactly the same way. Note 
 the temperature of the oil it should be 60 degrees F. Divide the time 
 for the oil to run by that required for the water the quotient is the 
 viscosity number. 
 
 EXERCISE IV. 
 
 Flash and Fire Test: Place the oil to be tested in a cup, or iron 
 crucible, if a standard tester is not available. Place on a sand bath and 
 suspend a thermometer from a ring so that the bulb is completely im- 
 mersed but does not touch the bottom of the oil cup. Apply heat, but 
 do not have the temperature rise faster than 2F. per minute. Keep 
 partially covered with a split glass. Test by wafting a tiny flame over 
 the surface of the oil once a minute. The tip for this flame may be made 
 by taking a wash bottle tip and inserting it in the end of the gas tubing. 
 
 For lubricating purposes oils should not flash under 250 F. 
 
 In testing kerosene and ordinary illuminating oils, the heat is raised 
 further until the gas evolved from the surface of the oil not only flashes 
 momentarily, but burns continuously. The first temperature is the 
 "flash point," the second the "flame point" or "fire test." The most 
 usual flash point required for kerosene is 110 F. The flame point is 20 
 degrees higher. 
 
 On the same oil an open tester will give a reading about 10 per cent 
 higher than a closed tester. 
 
124 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 EXERCISE V. 
 
 Acid Test: Obtain 2 oz. (60 c.c.) of alcohol from the storeroom. 
 Add 2 or 3 drops of phenolphthalein and run in slowly N / 10 potassium 
 hydroxide solution to obtain a very faint pink tinge. Now add 10 c.c. 
 of the oil. If this is thick, take a clean beaker, weigh and run in about 
 10 c.c. of the oil and reweigh ; divide by the specific gravity, getting the 
 volume. Now add the alcohol to this and heat up to 100 F. Titrate 
 with N / 10 potassium hydroxide to a permanent pink, stirring well after 
 each addition. 
 
 If more or less than 10 c.c. 'have been used, calculate how much 
 would have been required for 10 c.c. and call this the "acid number." 
 
 EXERCISE VI. 
 
 Maumene's Test: Weigh the beaker and introduce as nearly as 
 possible 50 grams of the oil. Introduce a thermometer, and while stir- 
 ring vigorously add 10 c.c. c.p. concentrated sulphuric acid. Note care- 
 fully the rise in temperature. 
 
 Petroleum oils rise only slightly, unsaturated vegetable and animal 
 oils give a higher rise in temperature. 
 
 Consult table 5 in the Appendix on Maumene's test and a table of 
 the oils commonly used. Report the rise as Maumene's Test. 
 
APPENDIX 
 
 TABLE 1 
 INTERNATIONAL ATOMIC WEIGHTS 
 
 
 
 Atomic 
 
 
 
 Atomic 
 
 
 Symbol. 
 
 weight 
 
 Symbol. 
 
 weight 
 
 Aluminum 
 
 Al 
 
 27.1 
 
 Neodymlum 
 
 Nd 
 
 144.3 
 
 Antimony 
 
 .... Sb 
 
 120.2 
 
 Neon 
 
 Ne 
 
 20.2 
 
 Argon 
 
 A 
 
 39.88 
 
 Nickel 
 
 Ni 
 
 58.68 
 
 Arsenic 
 
 As 
 
 74.96 
 
 Niton (Radium 
 
 
 
 Barium 
 
 Ba 
 
 137.37 
 
 emanation) 
 
 Nt 
 
 22.4 
 
 Bismuth 
 
 Bi 
 
 208.0 
 
 Nitrogen 
 
 Os 
 
 190.9 
 
 Boron 
 
 B 
 
 11.0 
 
 Osmium 
 
 
 
 16.00 
 
 Bromine 
 
 .... Br 
 
 79.92 
 
 Oxygen 
 
 Pd 
 
 106.7 
 
 Cadmium 
 
 Cd 
 
 112.40 
 
 Palladium 
 
 P 
 
 31.04 
 
 Caesium 
 
 .... Cs 
 
 132.81 
 
 Phosphorus 
 
 Pt 
 
 195.2 
 
 Calcium 
 
 Ca 
 
 40.09 
 
 Platinum 
 
 K 
 
 39.10 
 
 Carbon 
 
 C 
 
 12.00 
 
 Potassium 
 
 Pr 
 
 140.6 
 
 Cerium 
 
 Oe 
 
 140.25 
 
 Praseodymium 
 
 Ra 
 
 226.0 
 
 Chlorine 
 
 .... Cl 
 
 35.46 
 
 Radium 
 
 Rh 
 
 102.9 
 
 Chromium 
 
 Cr 
 
 52.0 
 
 Rhodium 
 
 Rb 
 
 85.45 
 
 Cobalt 
 
 .... Co 
 
 58.97 
 
 Pubidium 
 
 Ru 
 
 101.7 
 
 Columbium 
 
 Cb 
 
 93.5 
 
 Ruthenium 
 
 Sa 
 
 150.4 
 
 Copper * 
 
 Cu 
 
 63.57 
 
 Samarium 
 
 Sc 
 
 44.1 
 
 Dysprosium 
 
 .... Dy 
 
 162.5 
 
 Scandium 
 
 Se 
 
 79.2 
 
 Erbium 
 
 Er 
 
 167.7 
 
 Selenium 
 
 Si 
 
 28.3 
 
 Europium 
 
 Eu 
 
 152.0 
 
 Silicon 
 
 Ag 
 
 107.88 
 
 Fluorine 
 
 F 
 
 19.0 
 
 Silver 
 
 Th 
 
 232.42 
 
 Gadolinium 
 
 Gd 
 
 157.3 
 
 Sodium 
 
 
 
 Gallium , 
 
 Ga 
 
 69.9 
 
 Strontium 
 
 Sr 
 
 87.63 
 
 Germanium 
 
 .... Ge 
 
 72.5 
 
 Sulphur 
 
 S 
 
 32.07 
 
 Glucinum 
 
 Gl 
 
 9.1 
 
 Tantalum 
 
 Ta 
 
 181.5 
 
 Gold 
 
 Au 
 
 197.2 
 
 Tellurium 
 
 Te 
 
 127.5 
 
 Helium 
 
 He 
 
 3.99 
 
 Terbium 
 
 Tb 
 
 159.2 
 
 Holmium 
 
 Ho 
 
 163.5 
 
 Thallium 
 
 Tl 
 
 204.0 
 
 Hydrogen 
 
 H 
 
 1.008 
 
 Thorium 
 
 Th 
 
 232.40 
 
 Indium 
 
 In 
 
 114.8 
 
 Thulium 
 
 Tm 
 
 168.5 
 
 Iodine 
 
 I 
 
 126.92 
 
 Tin 
 
 Sn 
 
 119.0 
 
 Indium 
 
 .... Ir 
 
 193.1 
 
 Titanium 
 
 Ti 
 
 48.1 
 
 Iron 
 
 Fe 
 
 55.84 
 
 Tungsten 
 
 W 
 
 184.0 
 
 Krypton 
 
 Kr 
 
 82.92 
 
 Uranium 
 
 U 
 
 238.5 
 
 Lanthanum 
 
 La 
 
 139.0 
 
 Vanadium 
 
 V 
 
 51.0 
 
 Lead 
 
 Pb 
 
 207.10 
 
 Xenon 
 
 Xe 
 
 130.2 
 
 Lithium 
 
 Li 
 
 6.94 
 
 Ytterbium 
 
 
 
 Lutecium 
 
 .... Lu 
 
 174.0 
 
 (Neoytterbium) . 
 
 Yb 
 
 173.0 
 
 Magnesium 
 
 ....< Mg 
 
 24.32 
 
 Yttrium 
 
 Yt 
 
 89.0 
 
 Manganese 
 
 Mn 
 
 54.93 
 
 Zinc 
 
 Zn 
 
 65.37 
 
 Mercury 
 
 .... Hg 
 
 200.6 
 
 Zirconium 
 
 Zr 
 
 90.6 
 
 Molybdenum 
 
 Mo 
 
 96.0 
 
 
 
 
 125 
 
126 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 TABLE 2 
 
 Table for Calculating the Specific Gravity of Oils at 15.5 C. 
 
 C. H. Wright, Jour. Soc. Chem. Ind. 26, 513. 
 Example: A=sp. gr. at 20 Axl.00319=sp. gr. at 15.5 C. 
 
 Tem- 
 
 
 Tem- 
 
 
 Tem- 
 
 
 Tem- 
 
 
 pera- 
 ture. 
 
 Factor 
 
 pera- 
 ture 
 
 Factor, 
 
 pera- 
 ture. 
 
 Factor, 
 
 pera- 
 ture. 
 
 Factor, 
 
 
 
 
 C 
 
 
 C 
 
 
 C 
 
 
 10 
 
 0.99612 
 
 14 
 
 0.99894 
 
 18 
 
 1.00177 
 
 22 
 
 1.00462 
 
 11 
 
 0.99683 
 
 15 
 
 0.99965 
 
 19 
 
 1.09248 
 
 23 
 
 1.00534 
 
 12 
 
 0.99782 
 
 16 
 
 1.00935 
 
 20 
 
 1.00319 
 
 24 
 
 1.00605 
 
 13 
 
 0.99823 
 
 17 
 
 1.00106 
 
 21 
 
 1.00391 
 
 25 
 
 1.00677 
 
 TABLE 3 
 
 REPRESENTATIVE SAMPLES OF LUBRICATING OILS 
 
 By Albert F. Seeker, 
 From Van Nostrand's Chemical Annual. 
 
 Name, 
 
 Sp. Gr. 
 
 60 F 
 
 Flash 
 
 T?8t 
 
 op, 
 
 Fire 
 Test 
 
 O T7 
 
 Cold 
 Test 
 F 
 
 Saponifi- 
 able 
 Matter 
 
 Ash 
 
 Acidity 
 or alka- 
 linity. 
 
 Air Compressor oil 
 
 . 8857 
 
 455 
 
 525 
 
 25 
 
 trace 
 
 none 
 
 neutral 
 
 Air Compressor oil 
 
 0.8654 
 
 410 
 
 460 
 
 -2 
 
 none, 
 
 none, 
 
 neutral 
 
 Car oil 
 
 . 8824 
 
 354 
 
 400 
 
 5 
 
 none, 
 
 none 
 
 neutral 
 
 Cutting oil 
 
 O.i>036 
 
 345 
 
 425 
 
 31 
 
 82.9$ 
 
 none 
 
 1 16$ 
 
 Cylinder oil 
 
 8921 
 
 535 
 
 600 
 
 60 
 
 20$ 
 
 trace 
 
 neutral 
 
 Cylinder oil 
 
 9020 
 
 545 
 
 600 
 
 31 
 
 2.4$ 
 
 none 
 
 neutral 
 
 Cylinder oil 
 
 8993 
 
 590 
 
 600 
 
 
 none, 
 
 06$ 
 
 neutral 
 
 Cylinder oil 
 
 8992 
 
 555 
 
 600 
 
 
 
 none. 
 
 08$ 
 
 neutral 
 
 Engine oil . . . 
 
 9163 
 
 430 
 
 480 
 
 27 
 
 1.5$ 
 
 trace 
 
 neutral 
 
 Engine oil . . . 
 
 8845 
 
 360 
 
 415 
 
 5 
 
 10$ 
 
 none 
 
 05$ 
 
 Engine oil 
 
 8970 
 
 400 
 
 465 
 
 3 
 
 none, 
 
 none 
 
 neutral 
 
 Engine oil .... 
 
 0.8810 
 
 405 
 
 470 
 
 14 
 
 none, 
 
 C 02$ 
 
 neutral 
 
 150 Fire test oil 
 150 Fire test oil 
 
 0.7864 
 0.8206 
 
 140 
 266 
 
 180 
 300 
 
 32 
 
 none, 
 none, 
 
 none, 
 none, 
 
 neutral, 
 neutral 
 
 High fepeed engine oil 
 
 0.9152 
 
 400 
 
 465 
 
 5 
 
 17.2$ 
 
 0.06$ 
 
 1 09$ 
 
 High speed engine oil 
 
 0.9149 
 
 400 
 
 475 
 
 3 
 
 15.3$ 
 
 0.04$ 
 
 1 06$ 
 
 Ice machine oil 
 
 0.8941 
 
 430 
 
 495 
 
 -4 
 
 none, 
 
 0.13$ 
 
 neutral 
 
 Machine oil 
 
 8689 
 
 420 
 
 480 
 
 
 
 trace, 
 
 none, 
 
 neutral 
 
 Marine engine oil 
 
 8812 
 
 405 
 
 440 
 
 17 
 
 none 
 
 trace 
 
 neutral 
 
 Marine eng'ne oil 
 
 8765 
 
 435 
 
 500 
 
 5 
 
 none, 
 
 05$ 
 
 neutral 
 
 Marine engine oil 
 
 0.9090 
 
 405 
 
 464 
 
 
 
 12.0$ 
 
 15$ 
 
 75$ 
 
 Marine engine oil 
 
 9054 
 
 400 
 
 470 
 
 9 
 
 9.0$ 
 
 11$ 
 
 50$ 
 
 Screw cutting oil 
 
 9002 
 
 380 
 
 425 
 
 15 
 
 25$ 
 
 none, 
 
 1 0'^ 
 
 Transformer oil 
 
 . 8646 
 
 365 
 
 430 
 
 2 
 
 none. 
 
 none, 
 
 neutral 
 
 
 
 
 
 
 
 
 
CONSTANTS OF LUBRICATING OILS 
 
 127 
 
 TABLE 4 
 
 Chemical Constants of Oils. 
 
 By Albert F. Seeker. 
 Compiled from Van Nostrand's Annual. 
 
 Name, 
 
 Mixed Fatty Acids 
 
 Melting Point, C. 
 
 Acid Value. 
 
 Iodine Value. 
 
 Castor 
 
 13 
 25-27 
 21-25 
 17-23 
 34-40 
 33.2-37.4 
 17-21 
 19.2-31-0 
 26-36.4 
 16-19 
 31-43.8 
 
 192.1 
 258-266 
 204-207 
 198-4 
 202-298 
 
 87.93 
 8.4-9.3 
 130.5 170 
 119.5 . 
 111-115 
 
 Cocoanut 
 
 
 Corn (Maize) 
 
 Cottonseed 
 
 Lard Oil 
 
 Linseed 
 
 197 
 193 
 101.6 
 185 
 188.8 
 
 179-182 
 86-90 
 96-103 
 99-103 
 144-159 
 
 Olive 
 
 Peanut (Arachis) 
 
 Rape (Colza) 
 
 Tung (Chinese wood oil) 
 
 TABLE 5 
 
 Maumene's test, showing the rise in temperature of common oils. 
 From Stillman's Engineering Chemistry, 4th Edition. 
 
 Name of Observer. 
 
 
 Maumene 
 
 Schaedler. 
 
 Arch butt 
 
 Allen. 
 
 Stillman. 
 
 Lard oil 
 
 C 
 
 40 
 
 C 
 
 C 
 
 C 
 41 
 
 C 
 39 5 
 
 Tallow oil 
 
 41-43 
 
 
 
 
 39 
 
 Neat's foot oil 
 
 45 
 
 50 
 
 43 
 
 
 40 
 
 Oleo oil 
 
 
 
 37* 
 
 38* 
 
 37 
 
 Elain oil 
 
 
 
 
 
 38 
 
 Sperm oil 
 
 
 
 51 
 
 45 47 
 
 48 
 
 Whale oil 
 
 
 
 92 
 
 91 
 
 92 
 
 Menhaden oil 
 
 
 
 123-128 
 
 126 
 
 128 
 
 Dog-fish oil 
 
 
 
 
 
 80 
 
 Cod liver oil 
 
 102-103 
 
 103 
 
 
 113 
 
 110 
 
 Crude cotton seed oil. 
 
 
 69.5 
 
 70 
 
 67 69 
 
 74 
 
 Rape oil 
 
 58 
 
 
 
 
 60 
 
 Castor oil 
 
 47 
 
 48 
 
 46 
 
 65 
 
 45 
 
 Olive oil 
 
 42 
 
 43 
 
 41-45 
 
 41-43 
 
 42 
 
 Rosin oil 
 
 
 28 
 
 
 18-22 
 
 10 
 
 Mineral lubricating 
 oil 
 
 
 
 
 3-4 
 
 3 
 
 Earth nut 
 
 67 
 
 67 
 
 47-60 
 
 
 
 Sea Elephant 
 
 
 
 
 
 65 
 
 Corn oil 
 
 
 
 
 
 85 
 
 
 
 
 
 
 
128 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 INDEX 
 
 PAGE 
 
 Air Analysis 121 
 
 Alkalinity of Water 86 
 
 Calculations 92 
 
 Total 91 
 
 Ash in Coal 46 
 
 Corrected Ash 46 
 
 Determination of 95 
 
 Penalties for excess 64 
 
 Available Hydrogen ,.49, 54, 1 19 
 
 Boiler Waters 5-26 
 
 Analysis of 85 
 
 Calculations for treatment 24 
 
 Industrial methods of purification 16, 22 
 
 Rating of 8, 23 
 
 Table with calculations for treatment 26 
 
 Calculations involving unit coal 47 
 
 Coal values for commercial guarantees 52 
 
 In settlement of contracts 63, 64 
 
 Calculations from air dry to dry coal 4/1, 96 
 
 From dry to as received 44, 96 
 
 Calorific Values 49 
 
 By calculation from formula 49, 53 
 
 Computations in connection with the oxygen bomb in 
 
 Oxygen Bomb method 108-1 14 
 
 Peroxide method 97, 103 
 
 Berthier's test 53 
 
 Calculated by formula 49 
 
 Definitions 49 
 
 Direct determination 54, 55, 56 
 
 Peroxide Bomb method 57 
 
 Radiation corrections 56 
 
 Carbon Dioxide in Waters 14 
 
 Excess 14 
 
 Free and half bound I4 
 
 Classification of Waters 8, 23 
 
 According to type of mineral constituents ' n 
 
 As used by the C. B. & Q. R. R 23 
 
 By the Association of Railway Chemists 8 
 
 Coal A - :-~: - 29 
 
 Analysis ^ 
 
 Classification ^ o 
 
 Deterioration 55 
 
 Production, annual _" 29 
 
 Sampling ..'"'^""'"'""'^2-43 
 
 Spontaneous combustion 66 
 
 Storage "ZZZZ'Z ".".".".66, 70 
 
 Combustion of Coal 6=5 
 
 Smoke prevention 65 
 
 Corrosive ingredients of water "."...".. n 
 
 Dry Coal 4 
 
 Dulong's Formula 
 
INDEX 129 
 
 PAGE 
 
 Feldspar, Decomposition of 7 
 
 Fixed Carbon 48 
 
 Determination of 96 
 
 Flue Gas 71 
 
 Analysis of - HQ 
 
 Calculation of volumes and weights 72, 73 
 
 Loss of heat 74 
 
 Ratio of air entering to air used 73 
 
 Solutions for analysis of 120 
 
 Foaming ingredients 10 
 
 Fuel 27 
 
 Analysis 31 
 
 Production 29 
 
 Ratios 30 
 
 Resources _ 29 
 
 Types 27, 28 
 
 Gypsum, Solubility of 7 
 
 Hardness 87 
 
 Negative ~. 88 
 
 Permanent 87 
 
 Total 88 
 
 Illinois Coals 59 
 
 Composition of 60 
 
 Lime, Use of 13 
 
 Hydrated 15 
 
 Impurity allowed for 1 5 
 
 Solubility of 15 
 
 Use of in water treatment 15 
 
 Lubricants 76, 77 
 
 Methods for testing * 78, 122. 123 
 
 Mineral constituents of water 5 
 
 Analysis 85-92 
 
 Characteristics ; 6 
 
 Source 5 
 
 Moisture in Coal. Importance of Control 38 
 
 Determination of _ 94, 95 
 
 Loss in sampling 38 
 
 Oils 77 
 
 Analysis of 122 
 
 Specific gravity 122 
 
 Viscosity 123 
 
 Sampling of Coal 32-43 
 
 Amount required 33 
 
 Ash variations 36 
 
 Car lots 38 
 
 Care, material 33 
 
 Commercial samples 32 
 
 Composite 39 
 
 Face samples 32 
 
 Grinder for 34 
 
 Hand samples 32 
 
 Mechanical sampling 40 
 
 Moisture control 38,43 
 
 Sizes 34 
 
130 THE CHEMICAL EXAMINATION OF WATER, FUEL, ETC. 
 
 PAGE 
 
 Scaling ingredients .................................................................................................................. 8 
 
 Effect of .............................................................................................................................. 9 
 
 Soda Ash .................................................................................................................................... 15 
 
 Use of in water treatment .......................................................................................... 15, 16 
 
 Specifications for coal contracts .......................................................................................... 61 
 
 Bids and awards ............................................................................................................ 62, 63 
 
 Calculations for settlement .................................. . ..................................................... 63, 64 
 
 Double standard of reference ...................................................................................... 61 
 
 Penalties for Ash .............................................................................................................. 64 
 
 Price and payment ............................................................................................................ 63 
 
 Spontaneous Combustion ........................................................................................................ 66 
 
 Oxidation stages ................................................................................................................ 67 
 
 Standard solutions .................................................................................................................... 79 
 
 Calcium chloride ........................................................................ . ..................................... 82 
 
 Soap solution ..................................................................................................................... 82 
 
 Sodium carbonate ............................................................................................................ 80 
 
 Sulphuric acid ..................... . .............................................................................................. 81 
 
 Storage of Coal ........................................................................................................................ 66 
 
 Deterioration ................................................................................. .-. ................................... 66 
 
 Iron pyrites, effect of ...................................................................................................... 67 
 
 Methods ................................................................................................................................ 70 
 
 Moisture, Influence of .................................................................................................... 68 
 
 Oxidation and heat stages ............................................................................................ 67 
 
 Spontaneous combustion ................................................................................................ 66 
 
 Weathering ....................................................................................... . .................................. 69 
 
 Sulphur, Determination of .................................................................................................... 81 
 
 Curve .................................................................................................................................... 107 
 
 In Coal ................................................................................................................................ 103 
 
 In Waters ........................................................................................................................ 81, 90 
 
 Photometer .......................................................................................................................... 104 
 
 Sulphur in Coal ................................................. . ...................................................................... 48 
 
 Total Carbon in Coal, Use of ...................................................................................... 49, 73, u 
 
 Apparatus for measuring .............................................................................................. 115 
 
 Determination of ........................................................................................................ 115-118 
 
 Table for weight of carbon ............................................................................................ 118 
 
 Treatment of boiler waters .................................................................................................. 12-26 
 
 Industrial appliances ........................................................................................................ 16 
 
 Lime as used for .............................................................................................................. 13 
 
 Tabulated scheme for ...................................................................................................... 13 
 
 Ultimate analysis of Coal ...................................................................................................... 115 
 
 Unit Coal .................................................................................................................................... 46 
 
 Calculation of commercial values from ...................................................................... 46 
 
 Classification by means of .............................................................................................. 5: 
 
 Formula for deriving heat values ........................................................................ """.". 50 
 
 Formula for calculating .................................................................................................. 47 
 
 Heat values of .................................................................. 50 
 
 Volatile matter in Coal ..................................................................................................... 48 
 
 Determination of .............................................................................................. \"..'".""~g5, 96 
 
 W r ater for industrial use ....................................... 5 _ 2 6 
 
 " 
 
 Classification ..................... . .................................................... 8-23 
 
 Treatment .. Vfi-?> 
 
 wet coal ................................. zzzzizzzzzzzz 44 
 
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