T P
F ILL1NOIS BULLETIN
DECEMBER 22, 1908 No. 18
;ond-class matter under Act of Congress July 16. 1894 J
CIRCULAR NO. 3
FUEL TESTS WITH ILLINOIS COAL
(COMPILED FROM TESTS MADE BY THE TECHNOLOGIC BRANCH OF THE
UNITED STATES GEOLOGICAL SURVEY, AT THE ST. Louis FUEL
TESTING PLANT, 1904 JUNE 30, 1907).
BY
L. P. BRECKENRIDGE
AND
PAUL DISERENS
UNIVERSITY OF ILLINOIS
ENGINEERING EXPERIMENT STATION
URJBANA, ILLINOIS
PUBLISHED BY THE UNIVERSITY
<?
UNIVERSITY OF ILLINOIS
ENGINEERING EXPERIMENT STATION
CIRCULAR No. 3 DECEMBER 1908
FUEL TESTS WITH ILLINOIS COAL
(COMPILED FROM TESTS MADE BY THE TECHNOLOGIC BRANCH OF THE
UNITED STATES GEOLOGICAL SURVEY, AT THE ST. Louis, Mo., FUEL
TESTING PLANT, 1904-JuNE 30, 1907.)
BY
L. P. BRECKENRIDG,., DIRECTOR OF THE ENGINEERING EXPERIMENT STATION,
ALSO CONSULTING ENGINEER, TECHNOLOGIC BRANCH, U. S. G. S.
AND
PAUL DISERENS, M. E.
CONTENTS
Page
I. Introduction 2
II. A Summary of Conclusions 2
III. The Coals Tested 4
IV. Chemical Properties of the Coals Tested 9
V. Washing Tests 18
VT. Coking Tests 23
VII. Steaming Tests 26
VIII. Producer-Gas Tests 43
357045
EXPERIMENT STATION
I INTRODUCTION
The United States Geological Survey Technologic Branch has
conducted at the St. Louis, Missouri, fuel testing plant, a series
of investigations on the fuels of the United States. These tests
included a large number of Illinois coals. The results of the
tests have been published from time to time in a series of govern-
ment bulletins which contain very full descriptions of methods
and very complete details of the results obtained. A complete
list of the government bulletins is given at the end of this publi-
cation.
The tests included:
(a) Steaming tests under boilers
(b) Producer-gas tests
(c) Washing tests
(d) Coking tests
(e) Briquetting tests
(f) Chemical tests for composition and heating values
(g) Field work tests, sampling tests and a few other minor
investigations.
It is the purpose of this circular to present in compact form
the important results of the government tests so far as these tests
relate to Illinois coals. The Engineering Experiment Station
hopes that by bringing together in one circular the tests made by
the government on Illinois coals, it may do a service to the engi-
neering, industrial and fuel interests of the State. The compiler
has presented a few conclusions which seem justified by a study
of the results recorded from tests already made. It is, however,
fair to say that in a few cases the number of tests made is
scarcely sufficient to warrant any general application of the con-
clusions stated.
II A SUMMARY OF CONCLUSIONS
The results of the United States Geological Survey tests of
Illinois coal, presented in the following pages, seem to justify
the conclusions given below.
1. The chemical properties of the coals tested indicate that
FUEL TESTS WITH ILLINOIS COAL 8
VG
on a basis of the volatile-carbon total-carbon ratio (-77-), all Illi-
G
nois coals tested belong in Class B or Class D*. The maxi-
mum value of this ratio is 33.4 per cent and the minimum value is
20.9 per cent.
2. The average calorific value of Illinois coal is 14319 B. t. u.
per pound of pure coal (ash and moisture free). But few samples
tested varied from this value by an amount more than 2 per cent.
3. The quality of Illinois coal is greatly increased by wash-
ing. The reduction in ash and in sulphur is as follows:
When raw coal contains 8% ash, the reduction in ash is 20%.
When raw coal contains 12% ash, the reduction in ash is 30%.
When raw.coal contains 16% ash, the reduction in ash is 43%.
When raw coal contains 20% ash, the reduction in ash is 53%.
When raw coal contains 2% sulphur, the reduction in sulphur is 13%.
When raw coal contains 3% sulphur, the reduction in sulphur is 17%.
When raw coal contains 4% sulphur, the reduction in sulphur is 22%.
When raw coal contains 5% sulphur, the reduction in sulphur is 28%.
4. The material rejected by the washing jig contains I coal
and i noncombustible refuse.
5. One-fourth of the coal tested may be used for the manu-
facture of coke.
6. The evaporative efficiency of Illinois coal when burned in
a hand-fired furnace under a water- tube boiler averages 62.7 per
cent. This performance compares favorably with that of any other
bituminous coal tested at the United States Geological laboratory.
7. The evaporative efficiency of Illinois coal is but slightly
affected by the moisture contained in it.
8. The evaporative efficiency of Illinois coal decreases as the
ash and sulphur increase. Each additional per cent of ash and
sulphur results in 0.4 per cent decrease in efficiency.
9. The evaporative efficiency of Illinois coal, when burned in
a hand-fired furnace, decreases as the per cent of fine coal con-
tained in it increases.
10. Briquetting improves the evaporative efficiency of Illinois
coal only when the raw coal is in the form of slack or screenings.
11. The performance of Illinois coal in a gas producer com-
pares favorably with that of any other bituminous coal tested at
the United States Geological Survey laboratory.
12. The value of Illinois coal as fuel for a gas-producer
*Professor Parr's classification of coal, see page 11 of this circular.
4 ILLINOIS ENGINEERING EXPERIMENT STATION
decreases as the ash contained in it increases and as the calorific
value decreases.
13. In small plants it requires at least two and one-half times
as much coal to develop one horse- power when used in steam boiler
service as when used in gas producer service.
14. Gas producers can be continuously operated with Illinois
coal developing one electrical horse-power with 1.7 Ib. of dry coal.
Ill THE COALS TESTED
1. The mining centers and districts of Illinois, recognized by the
trade and defined with reference to geographical position, have
been described as follows.*
(a) Williamson, Franklin, and Perry Counties. Williamson
County led the production of the State in 1907 with more than
5,500,000 tons. No. 7, the Blue Band seam, which is from 5 to
10 feet thick, averaging 9 feet over a large area, is the greatest
producer. It maintains an approximate uniformity in physical
character and thickness but varies from place to place in fuel value.
At Spillertown another seam, 4 feet thick, is mined 60 feet below
No. 7. This seam is probably equivalent to No. 5 of Saline
County and may have a wide distribution in the Williamson
County district.
(b) Sangamon, Macoupin, Christian, Logan, and Macon
Counties. The Springfield district, extending into several adjoin-
ing counties, has long been one of the most important. Sangamon
produced more than 5,000,000 tons in 1907. The coal of the dis-
trict is commonly known as No. 5, though recent work tends to
confirm the suggestion that there are probably two distinct beds
mined in this district, -No 5, in the area north of Chatham, and in
No. 6 south of that town. The average thickness is a little less
than 6 feet at Springfield, about 4.5 feet at Decatur and from 6 to
8 feet in Macoupin County.
(c) St. Clair, Madison, Clinton, and Randolph Counties. St.
Clair County produced more than 4,500,000 tons in 1907. This
district, known as the Bellville district, is not sharply set off from
its neighbors since the same coal bed is mined under similar con-
ditions in adjoining counties. It is the Blue Band seam and has
a thickness of from 5 to 7 feet over much of the area. The seam
is reached by shafts from 100 to 300 feet deep.
* The Coal Resources of Illinois, by Prank W. DeWolf , Amer. Inst. of Mining Engineers,
October, 1908.
FUEL TESTS WITH ILLINOIS COAL 5
(d) Vermilion County. During 1907 Vermilion County pro-
duced nearly 3,000,000 tons. It has long been an important area,
shipping principally to the Chicago market. There are three per-
sistent seams, two of which are worked. The top or Danville,
No. 7, appears west of Vermilion river and is mined along the
outcrop and by shafts from 75 to 200 feet deep. The other, known
as the Grape Creek coal, No. 6, lies from 20 to 80 feet below the
Danville and is the more important of the two.
(e) Saline County. Saline County is one of the newest and
most rapidly growing producers. In 1907 its output was about
2,1*25,000 tons, a gain of 125 per cent over 1906. There are two
seams, No. 7 and No. 5, underlying the northern two-thirds of
this county and much of Gallatin on the east, each approximately
5 feet thick and lying 90 to 150 feet apart vertically.
(/) Fulton and Peoria Counties. Fulton County produced
more than 2,000,000 tons in 1907 and Peoria about half as much.
Here the principal seam, called No. 5, is from 4 to 4.5 feet thick.
Shafts reach the coal at from 75 to 150 feet. In all, seven beds
are present.
(g) La Salle, Bureau and Grundy Counties. The La Salle
district includes three principal counties and produces more than
5,000,000 tons yearly. The largest production is by long- wall
mining from seam No. 2, or the Third Vein. The coal averages
3 feet thick and is of good quality. About 140 feet above it, lies
seam No. 5. It is about 4 feet thick. About 40 feet above No. 5
is seam No. 7. This is extensively mined by room-and- pillar
methods.
2. The samples tested were procured from 5 of the 7 districts
described in the preceding paragraph. They were furnished by the
several coal mining companies of the state free of cost, and were
shipped to the fuel testing laboratory under the supervision of an
expert inspector whose chief care was to secure a sample for test-
ing which fairly represented the normal product of the mine. The
cars were numbered consecutively in the order of shipment, and
this number has been retained as the laboratory designation of
the sample. When two or more car lots consisting of different
grades, such as lump, nut, etc., were shipped from the same mine,
each lot was designated by a letter. For example, Illinois 11A
is screened coal, 11B run-of-mine and 11C No. 5 washed coal, all
from the same mine.
A complete list of the car-load samples of Illinois coal re-
ceived and tested is given in Table 1. In this table the location
ILLINOIS ENGINEERING EXPERIMENT STATION
r N
Min
gger Hollow No
CCCO-H <y M <
-2? OOO^ 66066 'S OO
rr
a
^
Co
:6
o-o a :
og o :: : s
2O -3 o :J ' bl
o o : ZH : : : : d^- gW: -
Sm
?l! :
iS|
SSv^to
SS'S
"?3
^5- .2 '^
|: I
O
I. g :s
S"S&|f- I
PU!Z;
's
I130O
S 'O 'S 'H
;^^^^2:
FUEL TESTS WITH ILLINOIS COAL
a d >-
. . . g|l, . g. d. |g
or s"3
Jc/}> S a? occ
'
b : : : -S -S |tf
a da : S ^^c'B
es ^a be ^sCa5
fl . ^^ : - c : |-a-g :
<j X < ffi < S < 23
FUEL TESTS WITH ILLINOIS COAL 9
of the mine, the geological bed or seam and the name of the mine
or its depth are given. Referring to the table it will be seen that
fifty-three car samples from thirty-three different mines were
tested, and that the mines are distributed throughout twelve of
the principal coal mining counties of the State. The location
of each mine is plotted on the map, Fig 1.
A comparison of the coal output of the several localities de-
signated in paragraph 2, with the number of mines submitting
samples, shows that the coal tested is fairly representative and
while it is true that two comparatively important coal producing
localities are not included, the results of tests should be accepted
as characteristic of Illinois coal in general.
3. The plan of the tests as adopted by the United States Geo-
logical Survey included a complete chemical analysis of samples
submitted, an investigation of the advantages of washing, an in-
vestigation of the coking qualities of the coal, and a series of boiler
and gas producer trials. In carrying out this plan each sample
was tested under conditions as nearly identical as possible, and
every effort was made to secure results which would admit of di-
rect comparison.
IV CHEMICAL PROPERTIES OF THE COALS TESTED
To determine the chemical properties of the coals tested,
samples were taken both from the working face of the mine and
from each car-load shipped.
4. The mine samples were obtained as follows: After a gen-
eral inspection of the mine to determine the variations of coal in
thickness and in quality, two representative points were selected in
opposite parts of the mine. The face of the coal at these places
was cleaned in order to remove any weathered coal or powder
smoke, and a cut made across the face of the coal from roof to
floor, including all the benches mined and such impurities as were
not removed in ordinary work. The coal obtained, amounting to
25 or 30 pounds, was pulverized and quartered down according to
generally accepted rules, and the sample placed in an air-tight
iron can. This was mailed to the chemical laboratory where it
was received and analyzed within two or three days.
10 ILLINOIS ENGINEERING EXPERIMENT STATION
5. The car samples were obtained during the process of unload-
ing at the testing plant. A quantity never less than 200 pounds
and often as great as 600 pounds was collected, a shovelful at a
time from every part of the car. This was thoroughly crushed and
quartered down until 25 or 30 pounds remained , placed in an air-
tight can and immediately shipped to the chemical laboratory.
Here the sample was pulverized and again quartered until a con-
venient amount for analysis was obtained .
6. The chemical work included calorific determinations, and
ultimate and proximate analyses. The calorific value was deter-
mined in duplicate for each car sample. A determination was also
made for one of the two mine samples corresponding to each car-
load. An ultimate analysis was made in duplicate on each car
sample. The approximate analysis and the determination of sul-
phur were made for practically every sample that came into the
laboratory, and were made in duplicate for all car samples.
7. The results of the chemical analyses are given in Tables 2
and 3, (p. 12, et seq.) Column 1 gives the laboratory number, Col-
umn 2 the U. S. G. S. number, Column 3, the coal bed or seam and
Column 4, the location from which the sample was taken. Column
5 gives the designation of the sample. The proximate analysis is
given in Columns 6 to 14. These results are given both for air-
dry coal (Columns 7 to 10) and for pure coal (Columns 12 to 14).
The calorific value is given in terms of dry coal in Column 11 and
in terms of pure coal in Column 15. Referring to the latter it will
be seen that the maximum value is 14900 and the minimum 13900,
a range of about 6.7 per cent. The average, however, is 14319
and but few of the recorded values vary from this by an amount
greater than two per cent. The ultimate analysis is given in Col-
umns 16 to 21. For convenience in comparing the results this is
put in terms of dry coal. Columns 22, 23 and 24 have been calcu-
lated from the ultimate and proximate analyses. The combustible
volatile is equal to the difference between the total volatile (Col-
umn 12) and the inert volatile (Column 23). The inert volatile is
equal to 100 minus the total carbon, the ash, the water, the sul-
phur and the available hydrogen all divided by 100 minus the ash
and water. The ratio of the volatile carbon to the total carbon
(Column 24) is equal to total carbon as shown by the ultimate anal-
ysis minus the fixed carbon as shown by the proximate analysis
divided by the total carbon.
FUEL TESTS WITH ILLINOIS COAL
11
The values included in Columns 22, 23 and 24 have been cal-
culated in order to make possible a classification based on the
ratio of volatile carbon to total carbon. This is the classification
suggested by Professor S. W. Parr, and, in brief, is as follows.*
VC
Anthracite Proper Ratio -^- below 4%
VC
Anthracite Semi- Anthracite Ratio -~- between 4% and 8%
VC
Semi-Bituminous Ratio -^ between 10% and 15%
VC
A \ Ratio -^ from 20% to 32%
( Inert Volatile from 5% to 10%
COAL
Bituminous Proper
Black Lignites
Brown Lignites
VC
B j Ratio -~ from 20% to 27%
Inert Volatile from 10% to 16%
VC
Ratio -^ from 32% to 44%
Inert Volatile from 5% to 10%
VC
D _j Ratio -^ from 27% to 44%
Inert Volatile from 10% to 16%
Ratio from 27% up
Inert Volatile from 16% to 20%
VC*
Ratio -^ from 27% up
Inert Volatile from 20% to 30%
It will be seen that in this system of classification all samples
of Illinois coal tested fall in one of two divisions, bituminous B
and bituminous D. In Table IV (p. 18) they have been arranged in
the order of their volatile-carbon total-carbon ratio. Referring to
VC
Column 2 of this table the minimum value of the ratio is 20.9
o
and the maximum 33.4. The inert volatile calculated on the pure
coal basis varies from 12.5 to 16.3.
The classification of the several coal beds or seams of the
state as used in the state coal reports has often been questioned;
nevertheless it is of interest to note that in so far as the present
tests can be taken as an index, seam No. 7 falls in Class B, and
seam No. 6 falls in Class D. Furthermore if, as has been pointed
out, (paragraph 2, section b, Chapter II) certain of the Blue Band
Composition and Character of Illinois Coals, by S. W. Parr, Illinois State Geological Sur-
vey, Bulletin No. 3.
12
ILLINOIS ENGINEERING EXPERIMENT STATION
f O CO O Oi O Ci C^ -OCO . CO 1C CO CO *
& . -r-< CD Oi -t-Oi . . I- ?o - co ** . cot-coio^
I-GOQ sana
jo punod jad-n ^ 'g
Proximate Analysis
of Pure Coal (Ash
and Moisture Free),
Per cent
jnijd^ns
UOQJ'BQ PSXT^
J831T?J^
["BOQ Ajp-JTV
jo punod aad -h "j -g
Proximate Analysis of Air-
Dry Coal, Per cent
qsy
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(M .
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" CCW "
a- - *
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FUEL TESTS WITH ILLINOIS COAL 13
g :23 = g :$o ;S3 ;S2 :S38 :gp :|8 :? :S :S :g2 :? :j? :g : :SS
* ' ' : ' '
o t
66:66:60:66:06:66: 6:66
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*
14
ILLINOIS ENGINEERING EXPERIMENT STATION
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W.S'J
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Proximate
of Pure Cc
and Moistu
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FUEL TESTS WITH ILLINOIS COAL
15
UOQJBO 81T1BIOA JO OtlBH
ysis of Dry Coa
cent)
loo aanj)
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qsy
areas J Psa T^OQ
oos ** -eo
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I : O1CO -CO ; .CO - ; : ^ -cQ | \
' '-oS ' -o ' -6 : : : D '6 :
CQ Q3Q
16 ILLINOIS ENGINEERING EXPERIMENT STATION
uoqji3Q iieaOiL oa
uoqa'BO 9U11310A jo omn
coot- . .iftwt-t- . .t- . .CD -m -os . .00 -oo
""" '* - ... - - ...
(sxsT?a 11300 ajnj)
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(sis^g IBOO QJtidD
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W W (M M IN W (N (M CC -CO <M -CO <N M
Ultimate Analysis of Dry Coal
(Per cent)
qsy
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^Hffioo -Tti^He^i^i i-i -co *c -o -o -oci
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FUEL TESTS WITH ILLINOIS COAL
17
os . r- cc -*" e<i cs
oo o . ~- oo i
ec c
:88 : :2
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-I- <&5
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6 -66 -66 -66 -66 -do -66 -6c> '.66 -66 ' ' '66 166 '.66 '.66
^O! r3 sXX cJ X 'V. -CT.
O
18
ILLINOIS ENGINEERING EXPERIMENT STATION
coals of Sangamon County in reality belong to Seam 6 instead of
5, Class B would also include all coals tested from seam No. 5.
The single sample from Seam No. 2, (U. S. G. S. 18) falls in Class
D, well up towards the lignites.
TABLE IV
CLASSIFICATION OF ILLINOIS COAL ON THE BASIS OF THE
VOLATILE-CARBON AND TOTAL-CARBON RATIO
U. S. G. S.
Number
Ratio of
Volatile
Carbon
to Total
Carbon
Inert
Volatile
(Pure Coal
Basis)
Class
Coal
Bed or
Seam
1
2
3
4
5
28
20.90
12.50
B
6
22.20
13.35
B
5
3
22.50
12.20
B
16
22.90
12.50
B
7
19
23.00
12.30
B
7
12
23.63
12.20
B
7
21
23.70
16.30
B
6
13
24.70
13.00
B
11
24.77
12,00
B
7
34
25.40
12.90
B
5
10
26.20
13.30
B
7
24
26.90
12.50
D
6
20
26.90
13.60
D
6
29
27.13
13.50
D
5
31
27.60
13.10
D
6
4
28.30
12.36
D
6
9
29.00
13.00
D
6
22
29,20
12-70
D
6
23
29.30
13.30
D
6
25
29.20
13.40
D
6
15
29 50
13.20
D
6
26
29 80
12.50
D
5
27
29.80
13.50
D
6
8
30.30
12.70
D
6
14
30.60
12-40
D
5
30
31.00
14.00
D
6
33
31.00
12.80
D
7
18
31.80
12.70
D
2
7
32.80
12.95
D
6
1 & 2
33.40
12.95
D
6
V WASHING TESTS
8. The equipment for the washing tests of Illinois coal consists
of one modified Stewart jig and one jig especially designed for
the laboratory, a Cornish tooth-roll crusher, an adjustable-mesh
bumping screen, and bins of suitable capacity for storing the coal.
The Stewart jig, shown in Fig. 2, provides for the washing of
coal not exceeding 1J inches in diameter. The special jig may be
used for larger sizes. It is of the center- plunger type, that is,
the plunger is directly beneath the screen. Its upward stroke
causes the pulsation, and its downward stroke, by an arrange-
ment of valves at the side of the jig body, admits the water sup-
FUEL TESTS WITH ILLINOIS COAL 19
ply. The screen is 4 feet wide by 5 feet long and is constructed
of No. 10 wire set 1-16 inch apart. The length of stroke and the
depth of the coal bed are adjustable.
FIG. 2 STEWART JIG (PROF. PAPER 48, p. 1460)
9. The tests involved the weighing of the raw and washed
coal, and the refuse. Samples of the coal were collected before and
after it was fed to the jig. These were sent to the chemical lab-
oratory for analysis. Altogether 31 tests were made on 24 kinds
of coal.
10. The results of the tests are given in Table 5. Column 1 of
this table is the U. S. G. S. coal number, Column 2 the jig used
20
ILLINOIS ENGINEERING EXPERIMENT STATION
spanod
11300 PJUSU
i
re
spunod
w
'S .
^r9
^[91T5J'Bd9S)
anqd[ns
^T3g
g2
S^ Ju|
qsy
X''
(p9UltU.I919C[
A'[9JKJT?d9S)
jnqd[ns
S-H
O
.2 a
02 a;
qsy
>> o
o|
< .
< ^
a P S
I 3
R
S?A
CH
<W 1-H C* 1 ' 1 I T I <M ^1 (71 ^ li ^- G^ CM <7J T (T-^T-H^-T I (M CO CM T I I
OQUiirtOOQO
r i -.-TI- -oi-r
1 ':
: :
I o Ut lO -- CD CC ?O iO OO 1C ^O ^ J
-* rf Ci ifs <M t- t- oc x ;e
C5CiCS>fl=;CC CC rt 1-
ON 's ' ~s -a
^i ^ t^ eo c
<*-,-<*
; ; ;--
Sl!mi!l:
IldSv
11!
SrJ
~^
: : :3?
sssssssssss
gg^S?
?55
^i2
S2g
-s w
-o^^j,'^:^;^;"^^^
o ;;
'- 1C *
7' ~
g$
|w : 1^6
o eo oi oo ao i os od ffi *
" re :c in
:2^
!^
1C ^-' 05
Slack
Run of Mine
No. 5 Nut
Run of Mine crushed to 2 in.
Slack
Run of Mine crushed to 2 in.
Slack
Run of Mine crushed to 2 in.
Egg crushed to 2 in .
Lump crushed to 2 in.
Lump & Egg ( crus:rud to 2 in.
Lump crushed to 2 in
Screenings crushed to 2 in.
Lump crushed to 2 in.
Nut & Slack crushed to 2 in.
Lump crushed to 2 in.
Screenings crushed to 2 in.
Nut crushed to 2 in.
Run of Mine crushed to 2 in.
Lump crushed to 2 in.
Screenings crushed to 2 in.
Nut crushed to 2% in.
Nut crushe i to 1 in.
Screenings crushed to 1 in.
vart
modified
"sS
as |
%
..B
3<
^ c - ^ 12 ~ !2 Z . & ^
i* iri ci w 75
5Sw
w <M ?;
%%%%
FUEL TESTS WITH ILLINOIS COAL
21
and Column 3 the size of the coal. The proximate analysis of the
raw and washed coal is given in Columns 4 to 11. The weight of
raw coal tested is given in Column 12 and the washed coal pro-
duced in Column 13. Column 14 gives the refuse expressed in per
cent of raw coal fed to the jig.
11. The improvement in quality of the coal effected by wash-
ing is well shown in Columns 4 to 11. For example the percent
of ash content is, in every case, decreased by washing. This is
shown graphically in Fig. 3. In this figure the per cent of ash
in the washed coal is plotted against per cent of ash in the raw
coal. The average line shows that by resorting to the process of
washing, it is possible to reduce the ash content from 22 per
cent to 8.7 per cent and from 10 per cent to 6.9 per cent. Ex-
pressed in per cent the amount of reduction is as follows:
When raw coal contains 8% ash, the reduction is 20%.
When raw coal contains 12$ ash, the reduction is 30%.
When raw coal contains 16 % ash, the reduction is 43%.
When raw coal contains 20 % ash, the reduction is 53%.
210
a
5-
in c
< 6
<
43
z:
O
4 6 8 10 12 14 16 18 20
Per Cent of Ash in Raw Coal
FIG. 3 REDUCTION OF ASH DUE TO WASHING
22
22
ILLINOIS ENGINEERING EXPERIMENT STATION
In a similar way the reduction in sulphur due to washing is
shown in Fig. 4. Referring to this figure it will be seen that:
When raw coal contains 2% sulphur, the reduction is 13%.
When raw coal contains 3% sulphur, the reduction is 17%.
When raw coal contains 4% sulphur, the reduction is 22%.
When raw coal contains 5% sulphur, the reduction is 28%.
73 4
o
12345
Per Cent of Sulphur in Raw Coal
FIG. 4 REDUCTION OF SULPHUR DUE TO WASHING
In bringing about this improvement in the quality of coal by
washing, much good coal which can not be recovered is carried
off with the refuse from the jig. For example, the tests show
that, based on the average of all tests, the refuse amounts to 16.8
per cent of the raw coal. The ash in the raw coal is 12.6 per cent,
but in the washed coal this is reduced to 8.34 per cent, therefore
12.6- 88.2X8.34 or 5.7 per cent is the ash content in the refuse.
It appears, then, that the material thus discharged is made up of
about | pure coal and i ash.
FUEL TESTS WITH ILLINOIS COAL 23
VI COKING TESTS
12. The ovens in which tests of the coking qualities of the
coal were made are of the regular beehive pattern. Originally
they were arranged in a battery of three, two of standard size,
12 feet in diameter, by 7 feet high, and the third 12 feet in diam-
eter by 6 feet 4 inches high; later, however, one of the standard
ovens was removed. Since the two remaining ovens may be con-
sidered as end ovens, that is, those placed at the ends of the bat-
tery, the results obtained are directly comparable.
13. The tests. To prepare the coal for test it was finely
crushed in a Williams mill. It was then placed on the larry and
delivered to the oven. The larry used when the work was begun
had a capacity less than one ton. This necessitated the filling and
emptying of the larry six or eight times before the charge was
complete. Each portion thus had time to emit a large amount of
gas and often to burst into flames before the next portion of the
charge was added. This resulted in much injurious cross lami-
nation of the coke in many of the earlier tests. Afterwards when
a larger larry was installed and the time of charging reduced
from one hour to less than seven minutes the laminations and
cross-breakage disappeared.
Directly after drawing the charge the ovens were closed for
a period of one or two hours during which time they were allowed
to gather heat for the next charge.
A sample of coal was taken at regular intervals as-the charge
was emptied into the larry. The total weight collected was 40 or
50 pounds. A sample of coke was taken from 5 different parts of
the oven, one piece 2 feet from the oven floor, one 2 feet from
each side on a line drawn from the center of the oven, one from
the center of the oven, and one 2 feet from the back wall: The
separate pieces of coke extended the whole height of the charge
and were as nearly uniform in size as possible.
14. The results of the tests are given in Table 6. Column 1 of
this table is the test number, Column 2 the U. S. G. S. number,
and Column 3 the size as shipped to the laboratory. The proxi-
mate analysis of the coal and coke produced from it is given in
Columns 4 to 13. Column 14 gives the weight of coal in the
charge. The coke produced in per cent of the weight of the coal
charged is given in Column 15, and the per cent of breeze in Col-
umn 16. The total yield as given in Column 17 is the sum of the
coke aod breeze produced. A brief description of the physical
24 ILLINOIS ENGINEERING EXPERIMENT STATION
.in -co in ^f Tf t- r- c<i . ^H co - . I-H in O3 r- T+H r- (M o o oc r- 02 oc
. t- T-I . . Cft IN ^ t- <M .0 !> -CO 5 00 00 -OS CO OO -3< Ol in - ^
Ajad'ea'Bdas
anqdins
of Coke
qsy
, Analysis
-
&
1
--
Aiai'e.i'Bdas
jmiding
s of Coal
qsy
e Analysi
Proximal
SS^A
1
"o
oj
'S*o's - n
, N , SS ,
-cow -^
-co * m co o co co >
Tt<O5 . D -
'-I'-I --^i -
i- w -e
.t~CO - -
-ioo .
' o o : '
TJ< cc o ~ n -i * M * m >n .
i-^OTjiTt<Ni-Tj<ineoint''ff -
x>cc^cO' ccoooscc ^
i- <N m -* 1-1 x i^- oo tt> M i
FUEL TESTS WITH ILLINOIS COAL
25
.fitctfi
26 ILLINOIS ENGINEERING EXPERIMENT STATION
properties of the coke produced is given in Column 18.
In reviewing the results of the tests as set forth in Table 6,
it should be remembered that the necessary routine work involved
in the testing of so many coals made it possible to make but few
tests on each coal. The data presented, therefore, show the
results obtained under conditions which of necessity had to be
controlled by observations made from time to time as the coking
proceeded, a procedure which tended to make the conditions of
operations by no means ideal.
Of the 37 tests made with Illinois coal 9 resulted in the pro-
duction of comparatively good coke and 14 in the production of
a poor grade of coke. The remaining 14 samples apparently proved
to be non-coking coals. Referring to the approximate analyses
of the coke produced it will be seen that in a number of cases the
quality of the coke is by no means inferior, though in all cases the
ash and sulphur content is slightly greater than is desirable.
Seven samples (11D washed, 13, 13 washed, 16, 22B washed, and
29 washed) were successfully used in a foundry cupola.
VII STEAMING TESTS
15. The apparatus comprising the plant for steam-ing tests con-
sisted of two standard Heine water- tube boilers equipped with
hand-fired furnaces and an Allis-Chalmers Corliss engine oper-
ating a 200 kilowatt Bullock generator. A plan and elevation of
one of the boilers and its setting are shown in Fig. 5 and the
general appearance as set up in the laboratory in Fig. 6.
The equipment used for testing the boilers provided conveni-
ent and accurate means for measuring the coal and water and for
making all observations of pressure, temperature, etc., specified
in the boiler testing code of the American Society of Mechanical
Engineers. It consisted principally of water-weighing tanks,
scales, charging cars, sampling cans, apparatus for analyzing flue
gases, pressure gages, calorimeters, thermometers and draft
gages*.
*This apparatus is described in detail in"Professional Paper No. 48" United States Geolog-
ical Survey.
FUEL TESTS WITH ILLINOIS COAL
27
28
ILLINOIS ENGINEERING EXPERIMENT STATION
i
FUEL TESTS WITH ILLINOIS COAL 29
The principal dimensions of the boiler and furnace are as
follows:
Length of drum feet 21.58
Inside diameter of drum inches 42.
Number of tubes, 11 tubes high by 11 tubes wide 116
Outside diameter of tubes inches 3.5
Width of furnace ' feet 6.16
Length of furnace feet 6.58
Mean height of furnace inches 26.00
Grate area square feet. . . 40.55
Ratio of grate area to air space 40. 17
Water-heating surface in tubes square feet . . .1897
Water-heating surface in water legs square feet ... 91
Water-heating surface in shell square feet. . . 43
Total water-heating surface square feet . . .2031
Ratio of heating surface to grate area 50. 1
16. The Tests. Since the establishment of the fuel testing
division of the United States Geological Survey, more than 500
boiler trials have been made, and of these, 112 involved the use
of Illinois coal. Tests were made with each of the 34 samples
submitted, the coal being used either in its natural state or in the
form of briquets, or both. A number of tests were also made
with washed coal.
A summary of the principal observed and derived results of
tests with Illinois coals is given in Tables 7 and 8. In these tables
only such values as have a direct relation to boiler performance
are included; additional data, however, may be found in the
reports published by the United States Geological Survey.*
17. The description of the coal tested given in Table 7, Column 1 ,
of this table is the serial number of the test and is useful as a means
of identification. Tlie number describing the location from which
the sample was taken, is given in Column 2 and the number of
the coal bed or seam, in Column 3. The size of the coal is given
* Bulletin No. 332 and Professional Paper No- 48.
30 ILLINOIS ENGINEERING EXPERIMENT STATION
in Columns 4 to 9. The size as shipped (Column 9) was not always
the same as that used in the tests since in some cases it was
crushed or screened after it was received. The actual size as
determined from samples taken during each test is given in pre-
cise terms in Columns 5, 6, 7 and 8, and the average diameter
calculated from these data is given in Column 9. The proximate
analyses (Columns 10 to 14) were made from samples collected
for each test and are given in the tables in terms of coal as fired.
Calorific values were not determined for every test. The values
given (Column 15) were calculated from the proximate analysis
and the calorific value determined from the car sample, on the
assumption that the B. t. u. per pound of pure coal (ash and mois-
ture free) is the same for each car load shipped to the testing
plant.
18. The performance of the boiler and furnace is given in Table
8. Column 17 gives the average boiler pressure in pounds per
square inch. The standard pressure was 75 but it will be seen
that the values given vary from 68 to 81. The draft above the
fire (Column 18) was measured in inches of water. In some tests
it was as great as .3 inch; the average however, is a little less
than .2 inch.
The furnace temperature (Column 19) was observed with a
Wanner optical pyrometer. The results .given are averages of a
number of readings which varied over a considerable range
throughout the test. The lowest temperature recorded is 1887
and the highest 2829 F.
The rate of combustion in terms of dry coal fired per hour,
per square foot of grate surface (Column 20) is, for most tests,
about 25 pounds. This rate, it will be seen, is sufficient to evap-
orate, in most cases 5i pounds of water from and at 212 F. per
square foot of heating surface per hour (Column 21) or 100 per
cent of the rated horse -power (Column 22).
The evaporative efficiency is given in Columns 23, 24 and 25.
In Columns 23 and 24 the equivalent evaporation per pound of
coal as fired and per pound of dry coal, respectively, is given.
The values given in Column 25 represent the over-all efficiency,
that is, the ratio of the heat absorbed by the water in the boiler
to the potential heat in the coal fed to the furnace. It is evident,
therefore, that this is the best measure of the value of any parti-
cular fuel for steam generation since it expresses the exact pro-
portion of heat purchased in the form of coal which can be con-
verted into useful energy in the form of steam. Referring to the
FUEL TESTS WITH ILLINOIS COAL
purio<j~jad r n -a
31
sgqoni '
of C
cen
T % o-j
qoni i 01
qoai i J9AQ
ON -s '0 *s
r* i ^ o
. . .<M . O'-*csot-ffi- / 5
-< ICCCXl-t-^r O
>oso "
! ITS iO 30 I
II
cc-^
Xt-
. ?o acac ceo o ac so 35
030 <N
; : 2: : 2
^^^S^si:^?,??
'g
:^x
c3 bl
& a
3 33 "
<D 4D <D F t> t> l t t> 00 00 Ok <3 Oft Ok Ok Ok O O O O O
32
ILLINOIS ENGINEERING EXPERIMENT STATION
rBooA-jci 4 i
rh
IBOO ui
gXSSSMSSesSSSS^aSSSeSXSSgeSloCiSSSS
alysis of
ired
it
usv
SSSPSSSSSSSSSSSsSSSSSSSSSSSSeKSSSiS
noOT * M
CM
S3SS838?82&SSS!25S23Sgg38Sg;838|2g
COOOOt-OOOOTOlCCDCOTht-^-OI-COOOO <NW<Ni-ii^OOCi
Proximate Ar
Coal as F
per cer
.
S?A
-
SS8883Si8888S88&88885&$58%88S
COWCOCOCOCOCOCOCOCO(WCOCO*JCOCOCOCOCOCOCOCOOOCOfWCOCOCOCOWW<NW
0)
S>g>g2g23gS288c3Sc38c333S3c
ODcot^dcodoJoJco^oJcoddcDoioioidi-ie-iiftd oi -hi-cowcowco
sgqoui 'IBOQ jo
-O-CDO ^sgggg ^psggggggsssggggasB
Size of Coal
per cent
qoat ^ J9pufi
oo
O 9* 1-1 CO O CO CO CD Ifii TH CO O . -* CO CO O <M r- Ci 1ft Tt< CD CO * CO CO J^ <M CD ^
3381S3SS5 .Balsas .5s*ss8;i3,HS3i*83$5;i8
qoui %oi %
to
CO <N (M CO Tfi CO CO 1-1 CO CD O5 1-1 CO O CO O 1-1 CD t- O I-" OO CO OS CD O5 CO O <N t- CO
t-COOCDt-COlft !><N <0 S> T(H -100C500it-lO WLOWt-OOW^T^jH
qoui I 01 %
COOCOCCWift^ .^W^COCOOT .QOl>NI-<05t-t-t-W
^Z^Z :%Z^%% :^^^^^^
U.OUT I J8AQ
U3
OSCD-r-CO-^CO 00-*iCC-'*ilftCO .OCOO<MCO-<*"<MCiO^CO>O t-
S^S^SS : 8S8^ isliSeJSiciScSSlS^^ffi ' :
Size of Coal as Shipped
*
: : : : : : : : : : : ':':':': ': : i :::::::::::: i :
1 : : ::::::: : : : : : :
: : :::::;:::::::
: 1 : : j i i i i j
-a : :
a) : !
: -S i : : ': : i
. 58 . aj : : . ;
i : *: : : : - - : i i'S : :
: : S : : g -^ :^ : :
.2 d s3 fl . ; i 2 * "* "
S ' 'ii '^ r.s 'a : j ' ' -g > i^l '
"o, . &- - SSp. - - o. 0- ^^ P. - . a&opi&fi. .- - -
g: : g - - 00^- - - i- |S= o- S- - - SSSSSSC
s s ^'C s s 'C^j ^ s ^ s y 3 3 3""
P5 j ^pqas Di P3^ ^ J j^jjjj^
ureas JO pgg I'BOO
CO
CM
ON -s -o -s *n
CQ CO CO 3D CQ CO O O CO ^<5j<J<
'ON 5S9J,
*c r- 8 J5SsS)SgS g 5S 5 ; 5 ag 5^ 8SS s5 : $s8S8R
^^^^^^^CO-H^- ^
FUEL, TESTS WITH ILLINOIS COAL
SSS2?3?* = 2Si2j = S88 -"2S*S.H.i-228 w S""' < *8 -- : ->2 . :
a
i. 2
a i
...ii.
- S- - S- c-
5 5 S
i!
gc- -
C333
-r- - ~ ~. ~ ~. ~.
34
ILLINOIS ENGINEERING EXPERIMENT STATION
TABLE 8 STEAMING TESTS PERFORMANCE OF BOILER
AND FURNACE
u
S
Equivalent
Q
.r- Q2 C3
S
Pounds of
t- <U
cB
<D
?-
a
88 Q g'5
'O P
<D O
Water Evap-
[s
3.g
3
in PH en
C&n"c/2 g
||
orated from
and at 212 F.
pqO ^
)>3
CM > fl
o
fe
It
Is
1|
IP
f} 3'! -
2
Per Pound
in 0) G
III
09
H
2s
3&
^n
7^ S
o^g
u a v
|*KS
i|
^-d
c2 &fi f-i
fl G 0)
.SS^H
O^_, -
&!
I 5
03 O
6-9
f- 1 i
s
a
r
!2|*S
3|*
*
kg
85
fe
P
3
o
W
f
ii
**s
w
3
K
1
16
17
18
19 20
21
22
23
24 25
18
.18
1887
24.90
3.59
100.7
6.51
7.21
58.73
4.85
19
.15
22.36
3.57
100.1
7.16
8.00
61.47
4.38
38
.21
21.23
3.41
95.5
7.35 ! 8.04
60.39
4.34
48
.16
19.84
2.92
81.9
6.38 7.34
57.27
4.73
50
.21
23.13
3.36
94.2
6.36 7.27
56.36
4.80
73
.... .23
22.34
3.30
92.5
6.43 7.40
61.64
4.72
106
75
.25
22i3
25.94
3.39
95.3
5.56 6.56
49.64
5^32
313
72
.17
17.24
2.81
78.7
7.03 8.16
65.51
314
68
.07
2359
21.81 3.42
95.9
5.99 6.91
55.14
122
72 .30
20-08 2.19
61.4
5.44 6.08
58.71
5.74
129
73
.24
19.92
3.19
89.6
6.70 8-02
60.84
4.36
142
81
.16
20.07
2.97
83.3
6.65
7.44
61.39
4.70
143
79 .18
18.74
2.69
75.5
6.46
7.20
62.01
4.85
146
67 .22
20.21
2.68
75.2
6.64
7.40
64.45
4.72
516
79
.13
31.99
3.70
103.7
4.95
5.79
54.38
6.03
101
83.5
.32
28.82
3.21
90-1
5.39
6.22
49.86
5.61
102
78
.25
38.36
3.62
101.5
5.58
6.39
51.41
5.46
103
81 .27
22J8
26.53
3.61
101.1
5.94
6.81
52.59
5.13
104
80 . 19
2155
23.22
3.01
84.4
5.70
6.50
50. 2S
5.37
105
78 .25
2220
30.26
4.08
114.3
5.93
6.75
51.92
5.17
113
75 .20
25.60
3.05
85.6
5.68
6.66
49.67
5.24
121
75 .19
26.60
3.57
100.0
6.69
7.49
58.15
4.66
492
76.5 .16
3.50
98.2
6^65
7.79
62.50
4.48
107
76 .32
2229
2li()0
3.20
89.9
6.76
7.65
59.44
4.56
108
76 .21
22.24
3.13
87.6
6.39
7.04
53.60
4.96
109
78 .29
21.46 2.96
83.0
6.90
7.70
60.10
4.53
110
75 .26
20.66 ! 2.48
69.6
6.08
6.71
50.12
5.20
114
75 .21
24.23
3.52
98.7
7.16
8.11
57.82
4.30
137
74 .16
20.98
3.17
88.8
7.76
8.42
64.51
4.14
138
74 .18
2376
19.94
2.97
83.4
7.68
8.32
66.08
4.20
139
77 .18
2435
19.70
3.06
85.9
8.02
8.67
68.33
4.03
141
79 .15
18.81
3.11
87.3
7.66
8 29
64.02
4 21
111
73.5 ! .28
24.35
2.93
82.0
6.15
6.70
51.18
5.21
112
80 .27
22.36
2.90
81.2
6.59
7.23
54.65
4.83
115
76 .26
22.89
3.42
95.9
6.83
7.49
58.71
4.66
116
76
.22
24.19
3.61
101-3
6.94
7.48
55.85
4.67
117
75.5
.20
23.80
3.42
95.8
6.71
7.19
55.38
4.85
118
77 .16
23.16
3.32
93.1
6.74
7.19
54.26
4 85
119
75 . 25
25.70
3.75
105.0
.84
7.31
53.97
4.78
120
72
.23
25-41
3.55
99.5
.08
7.79
56.27
4.48
312
71
.11
2400
19-38
3.40
95.4
.96
8.80
63.60
127
73 .19
21.49
3 35
94.0
.15
7.81
63.04
4.50
128
75 -19
21.45
3.51
98.3
.54
8.19
65.07
4.26
131
74 .19
20-87
2.91
81.50
.04
7.74
64.08
4.49
133
81 .22
22-91
3.15
88-2
,00
7.67
62.51
4.55
135
74
,18
23.09 3.62
101.3
.86
8.75
64.48
3.99
136
75
.21
20.77
2.91
81.5
7.00
7.81
63.56
4.47
463
81
.11
2490
18-67
3.20
89.7
7.98
8.58
64.44
4.07
132
76
.13
22.06
3.37
94.5
7.67
8.52
65.67
4.10
134
78
.18
22.55
3.39
95.0
7.58
8.39
63.96
4.16
144
79
.10
20.42
3.70
103.8
8.20
9 . 08
66.12
3.84
145
75
.13
20.14
3.38
94.7
8.37
9.36
67.93
3.73
123
73
.28
23.60
3.10
87.0
6.49
7.34
59.03
4.76
125
74
.20
20.30
3.08
86.2
6.62
7.58
60.37
4.61
130
77
.14
21.63
3.33
93.3
6.49
7.71
58.48
4.53
126
69
.18
20.44
3.11
87.2
6.86
7.62
62.62
4,58
FUEL TESTS WITH ILLINOIS COAL
35
TABLE 8 STEALING TESTS PERFORMANCE OF BOILER
AND FURNACE (Continued)
8
s ^
Equivalent
Test No.
Boiler Pressure
Ib. per sq. in.
Draft above Fire
inches of Water
mperature of Furna<
Degrees F.
)ry Coal per sq. ft. ol
Grate Surf ace per
hour, pounds
niviilrnt. Kv;i]iui'nt.i(
Dm and at 2!2F. pei
ft. of Heating Surfa
Per Hour, pounds
Per Cent of Rated
orsepower Develope
Pounds of
Water Evap-
orated from
and at 21 2 F
Per Pound
Efficiency of Boiler
ncluding the Grate
Per Cent
s|J
1
3?
5f->
|
&
i i
&i
w o
s
M
3
1
16 17
18 19 20
21
22
23
24
25
152
75
.13
2439
19.63
3.36
94.3
7.57
8.59
63-30
4.06
150
74
.11
....
19.63
3.56
99.8
8.24
9.08
68.11
3.85
140
75
.18
18.51
2.86
80.1
-.60
8.61
64.20
4.06
147
72
.17
19.53
3.12
87.4
-.57
8.91
63.48
3.92
148
73
.19
18.86
2.99
83.9
-.06
7.94
59.02
4.40
149
74
.14
2060
17.83
3.29
92.2
-.70
9.23
66.36
160
77
.14
2428
18.47
3.07
86.1
-.27
8.33
61.71
4.'i9
161
77
.20
2080
17.77
3.12
87.6
-.62
8.80
65.82 3.97
163
78
.17
2227
20.79
3.57
100.2
7.50
8.61
63.63 4.06
170
79
.16
2039
20.22
3.10
87.0
-.42
8.56
64.29 4.08
171
77
.17
20.08
3.23
90.6
-.79
8.97
67.06 I 3.89
175
74
.09
2470
20.54
3.73
104.7
8.13
9.10
67.50 : 3.84
204
72.5
.11
2447
20.69
3.50
98.2
8.54
9.45
69.93 3.70
205
.12
2448
20.38
3.38
94.9
8.32
9.27
68.86 3.77
420
79.5
.12
....
19.95
3.35
93.9
7.67
8.40
65.26 ! 4.16
423
78.5
.14
....
16.94
2.89
81.0
7.73
8.53
65.92 I 4.09
424
83.5
.12
18.67
3.18
89.1
7.81
8.53
66.35
4.09
425
81
.14
19.33
3.32
93.0
7.87
8.61
66.73
4.05
421
82
.11
19.46
3.30
92.5
7.70
8.48
65.76
4.12
422
78.5
.12
19,46
3.39
95.0
7.88
8.73
67.03
4.00
292
70.5
.10
2020
15-49
2.37
66.3
6.55
7.66
64.75
4.56
301
69
.30
24.61
3.54
99.3
6.71
8.04
62 08
4.34
302
76
.17
2708
25.69
3.81
106.7
6.91 8.27
63.65
4.22
315
74.5
.16
2499
20.05
3.27
91.6
6.94 8.16
65.97
4.28
316
69
.15
2401
20.05
3.19
89.3
6.76
7.96
62.80
4.39
318
69.5
.04
2508
25.30
4.11
115.3
6.73
8.14
63.04
4.29
324
71.5
.20
2850
23.08
3.60
100.9
6.91 7.81
65.67
4.47
325
72
.18
2828
22.61
3.60
101.0
7.14 7.97
64.81
4.38
328
71
.14
2829
26.73
4.34
121.8
6.97
8.14
60.82
4.29
306
67
.13
2402
18.50
3.01
84.3
6.97
8.15
66.93
4.29
317
70.5
.13
2397
19.63
3.23
90.4
7.02 8.23
62.12
4.24
321
70.0
.27
23.75
3.78
106.0
6.89 | 7.97
59.22
4.38
322
74.5
.16
24.54
3.80
106.6
6.71 7.76
57.66
4.50
335
74.5
.22
2708
20.49
3.30
92.6
7.09 8.07
63.68
4.33
336
73.5
.26
21.48
3.29
92.3
6.71 7.67
58-68
4.55
337
72
.20
23.63
3.82
107.0
7.00 8.10
62.71
4.31
338
71.5
.21
21.36
3.10
87.0
6.38 | 7.28
56.16
4.80
339
73
.21
23.63
3.54
99.1
6.63 j 7.50
60.25
4.66
341
76
.34
20.91
2.84
79.7
6.56 7.58
60.85
4 61
342
77
.30
2264
23.02
3.16
88.6
6.47
7.67
60.42
4.55
353
78
.18
2360
19.83
3.14
88.0
6.66
7.93
64.73
4.40
354
76
.17
2162
19-26
3.08
86.4
6.75
8.02
66.12
4.36
459
80
.15
2601
18.72
3.13
87.7
7.75
8.36
64.29
4.18
457
81
.16
2606
19.85
3-42
95.9
8.13
8.64
64.99
4.04
448
79
.17
2862
22.52
3.88
108.8
8.21
8.63
64.50
4.05
452
82.5
.14
2833
21.97
3.94
110-5
8.35
8-98
66.35
3.89
465
75.5
-15
2665
20.35
3.62
101.5
7.65
8.91
65.58
3.92
460
81.5
.18
2759
21.38
3.44
96.3
7.16
8.05
65.08
4.34
461
80.5
.18
2816
22.32
3.72
104.2
7.31
8.34
63.28
4.19
466
79.5
.16
2784
22.32
3.90
109.2
7.87
8.74
66.14
3.99
511
79.5
.19
....
20.94
3.59
100.7
7.76 8.60
62.58
4.06
489
74
.14
21.16
3.49
97.7
7.06 ! 8.25
64.76
4.23
491
82
.20
21.65
3.56
100.0
7.35 i 8-24
64.51
4.24
513
82
.10
2465
26.41
3.23
90.7
5.43 6.13
53.34
5.69
509
82 .22
21.50
3.79
106.2
8.24 8.82
62.53
36 ILLINOIS ENGINEERING EXPERIMENT STATION
values given, it will be seen that but few fall below 55 per cent or
above 65 per cent, the maximum and minimum efficiency recorded
being 68.11 and 49.64 respectively.
In reviewing the results set forth in Tables 7 and 8 it should
be remembered that they apply only to the performance of a
hand-fired water-tube boiler of the Heine type and that any con-
clusions which may be drawn are thus limited. Had it been pos-
sible to provide a furnace especially adapted to the burning of
each particular coal, the relative efficiency as established by the
tests might have been slightly different. The results obtained,
however, may be accepted as fairly indicative of the value of the
coals tested. With this in view, then, it will be of more than ordi-
nary interest to study the effect of the physical and chemical prop-
erties of the fuel upon the performance of the boiler and furnace
as set forth in the tables.
19. Furnace temperature. It will be seen that while the
results do not show any exact relation between efficiency, furnace
temperature and rate of combustion, nevertheless they clearly
indicate that as the rate of combustion increases, the temperature
increases, but that efficiency is only slightly affected by change
in combustion-chamber temperature. A comparison with values
representing capacity (Column 22) shows that as the combustion
chamber temperature increases the capacity is increased.
20. The evaporative efficiency as affected by moisture in the coal
is not well defined by the results of the tests. While they seem
to indicate that coals high in moisture generally give low effi-
ciency it must be remembered that high moisture is often accom-
panied by high ash content or by poor mechanical structure,
either of which properties has a more deleterious effect on effi-
ciency than moisture. That this is true is emphasized by the fact
that the heat required to evaporate the water in Illinois coal con-
taining 15 per cent moisture is but little more than 1.5 per cent of
its total calorific value.
21. The effect of sulphur and ash upon evaporative efficiency.
Sulphur is an undesirable element in coal. It generally occurs
in combination with iron, as pyrites, and in combination with cal-
cium as gypsum. Of the two sulphur compounds, the former is
generally contained in larger quantity in coal and is harmful be-
cause it increases the tendency of the coal to clinker. The clinker-
ing is especially bad if the percentage of ash is small in proportion
to the sulphur. In such coals the pyrites and the ash fuse and
form- a thin layer of solid clinker, which effectively stops the
FUEL TESTS WITH ILLINOIS COAL 37
passage of air through the grate, thus permitting the grate bars
to become heated from the hot fuel bed just above. The heat
warps the grate bars and the clinker has such corrosive action on
the hot iron that destruction results in a short time. When such
clinkering occurs, any attempt to slice the fire fails and only slow
and very difficult cleaning of the fires will remove it. Most Illi-
nois coals having a large sulphur content are also high in ash so
that the injurious effect of sulphur is not so pronounced as in
some other coals. In making the tests it was found that the use
of steam served to prevent the clinker from melting into the grate
when the ash and sulphur content is large .
Referring to Columns 13, 14, and 25 of Tables 7 and 8 the
decrease in efficiency with increasing ash and sulphur will be read-
ily seen. In Fig. 7, which shows this relation graphically, efficiency
is plotted against per cent of ash plus sulphur based on dry coal,
for all tests run with lump, egg and nut coal. Although many of
the plotted points lie at a considerable distance from the average
line, its position and direction are rather well defined. It shows
that the efficiency drops from 66.5 per cent when the ash plus
sulphur is 10 percent to 55 per cent when ash plus sulphur is 30
per cent. For increases in ash and sulphur beyond 18 percent
the drop in efficiency is relatively rapid.
22. The effect of size on evaporative efficiency. The discussion
in the preceding paragraph does not take into account the fact
that size has much to do with the efficiency with which coal can
be burned, and this is one of the chief reasons for the poor alignment
of many of the points. The efficiency shown by the same tests
together with those made with slack have therefore been plotted
against size, expressed in percent of coal under i inch in diameter.
The resulting relation is shown in Fig 8. Here, too, the points are
widely scattered but the slope of the average line is fairly well
fixed. Thus a coal giving an efficiency of 66 percent when 10
percent of it is under i-inch in diameter, will give an efficiency
of only 62 per cent when 60 per cent of it is under i-inch in diam-
eter.
38
ILLINOIS ENGINEERING EXPERIMENT STATION
6 8 10 12 14 16 18 20 22 24 26 28 30 32
Ash -f Sulphur, Per Cent of Dry Coal
FIG. 7 EVAPORATIVE EFFICIENCY AS AFFECTED BY
ASH AND SULPHUR
10
FIG. 8
50
60
20 30 40
Size of Coal, Per Cent Under i Inch *
EVAPORATIVE EFFICIENCY AS AFFECTED BY
SIZE OF COAL
FUEL TESTS WITH ILLINOIS COAL
39
90
80
B
H 70
o
1 60
g 50
I"
iS 30
20
10
10 20 30 40 50 60
Size of Coal, Per Cent Under J Inch
FIG. 9 COMBINED EFFECT OF SULPHUR PLUS ASH AND
SIZE ON EVAPORATIVE EFFICIENCY
Fig. 9 has been drawn to show the combined effect of sul-
phur plus ash and size, on the evaporative efficiency of Illinois
coal. In it lines have been drawn showing the decrease in effi-
ciency with decrease in size for coals having 10, 20 and 30 per
cent ash plus sulphur based on dry coal. There are, of course,
other factors which affect efficiency but the results of the present
tests seem to point to these as the most important. The lines
given therefore, may be accepted as defining with considerable
accuracy, the performance of Illinois coal when burned in a hand-
fired furnace under a water-tube boiler.
23. Comparative efficiency resulting from the use of washed and
unwashed coal. It has been shown that the process of washing
Illinois coal is effective in reducing the ash and sulphur content.
That the evaporative efficiency of the coal thus treated is increased
follows directly from the facts just developed. The extent of the
40
ILLINOIS ENGINEERING EXPERIMENT STATION
improvement is set forth by Table 9. In this table tests are
grouped in the order of the size of coal used. A comparison of
the average values given shows that where slack is used washing
effects an increase of 4.2 per cent in evaporative efficiency, 2.3
per cent where nut is used, .7 per cent when run-of-mine is used
and .6 per cent when lump is used. The extremely small gain for
TABLE 9
COMPARATIVE EFFICIENCY OF WASHED AND UNWASHED COAL
U. S. G. S.
Coal
No.
Size
Efficiency
Unwashed
Washed
1
2
3
4
1
7C
10
Slack
Slack
Slack
58.73
58 71
50,12
61.47
60.84
57.82
60.04
Average
55.85
9A
12
R. o. m.
R o. m.
50.28
62.51
49.67
61.48
57.08
Average
56.40
13
13
Nut
Nut
65.67
63.96
67.93
66.12
Average
64.68
67.02
23 A
18
18
Lump
Lump
Lump
66.93
64.20
J.9.02
63.38
62.12
63 48
66.39
64.00
Average
the last two sizes named is explained by the fact that, in the pro-
cess of washing, the coal was crushed to a size under 2 inches, a
size which has been shown not to be so well adapted to the kind
of grate and furnace used as the larger size.
24. Comparison of efficiency resulting from the use of raw and
briquetted coal. Of the 112 boiler tests made, 15 tests were run
with briquetted coal. Comparing the results shown in Table 8
with the results of similar tests with raw coal, it will be seen that
in most cases where the raw coal is in the form of screenings or
FUEL TESTS WITH ILLINOIS COAL
41
slack, briquetting improves the evaporative efficiency, but where
it is in the form of egg, nut or lump, but little difference in perform-
ance results. As in the case of coal in its natural state, effi-
ciency decreases as the ash and sulphur content increases. This
is shown graphically in Fig. 10. The rather close alignment of
the plotted points in this figure is due principally to the uniform-
ity in size of the fuel.
H 7
2
O 60
8 10 12 14 16 18 20 22 24 26 28
Ash + Sulphur, Per Cent of Dry Coal
Fi(*. 10 EVAPORATIVE EFFICIENCY As AFFECTED BY
ASH AND SULPHUR IN BRIQUET
42
ILLINOIS ENGINEERING EXPERIMENT STATION
25. The evaporative efficiency of Illinois coal compared with
that of coal from other states, as shown by the United States Geolog-
ical Survey tests, is presented in Table 10. Only tests with bitumin-
ous and semi- bituminous coal are here included and the average
values given are based only on tests which were made under simi-
TABLE 10 COMPARATIVE RESULTS OBTAINED FROM COAL
FROM VARIOUS STATES
%
a ,.
||
ll
!
o
i
S " ^
^ ^
T^
3
,3
*o >
Ofe Q
Is
a
en
c3
43 <D
~o o
O 3
^ 'cd
o>
O
p Q
> ^ ^
Q, O
State
Kind of Coal
^
^
* 0>
H^Q
"o^
K
O
CD
c _, ^3
>>i
P. ^
6
6
Pt O
~ c
s P-*
,JQ
fa
fc
o>T
"3 c3 O
S^
^ w
> r) P.
'S'5
43
P
p
H M
pq
1
2
3
4
5
6
7
8
Alabama
Bituminous
10
4
91.9
8.43
64.31
12656
Arkansas .
EJituminous
8-
89.3
9.03
63.54
13707
Colorado
Bituminous
1
1
71.9
7.21
55.36
12577
Illinois .
Bituminous
52
25
89.6
7.95
62.66
12249
Iowa
Bituminous
5
5
90.7
7.13
59.55
11650
Indiana
Bituminous
24
11
89.5
8.23
63.76
12549
Kansas
Bituminous
8
6
83.4
8.10
61.26
12780
Kentucky
Semi-Bituminous
8
3
91.0
9.77
65.41
14417
Kentucky
Bituminous
3
3
88.9
8.37
62-82
12883
Missouri
Bituminous
9
92.2
7.73
60.18
12246
New Mexico
Bituminous
6
3
104.3
8.28
64.68
12507
Ohio
Bituminous
18
9
92.2
8.82
64.88
13130
Pennsylvania
Bituminous
18
9
89.9
9.75
66.22
14248
Tennessee
Bituminous
24
9
102.3
8.81
64.18
13261
Virginia
Semi-Bituminous
10
4
94.2
9.73
65.07
14436
West Virginia
Bituminousand Semi-
Bituminous
36
21
95.5
9.86
65.89
14451
FUEL TESTS WITH ILLINOIS COAL 43
lar conditions of operation. Column 1 gives the name of the state,
Column 2 the kind of coal, Column 3 the number of tests included
in the average, Column 4 the number of samples of coal, Column
5 the average rate of power developed, Column 6 the efficiency in
terms of equivalent evaporation per pound of dry coal, Column 7
the efficiency in per cent and Column 8 the heating value of the
coal in B. t. u., per pound of dry coal. The values given in the
table show that the average evaporative efficiency of Illinois coal
is 62.66 per cent. This compares favorably with the results from
any other coal tested and in fact is nearly identical with the gen-
eral average, 63.1.
VIII PRODUCER-GAS TESTS
26. The prod ucer-gas plant used for the United States Geolog
ical Survey tests of Illinois coal consists of two Taylor pressure
producers arranged to discharge into a single scrubber, a
Westinghouse three-cylinder vertical gas engine rated at 235
horse-power, and a six-pole, 175 kilowatt Westinghouse direct
current generator. Auxiliary apparatus was provided for meas-
uring accurately the coal and gas, the steam used by the producer,
and all temperatures and pressures necessary for a complete
determination of plant efficiency. The general arrangement of
the plant is well shown in Pig. 11, and a section through the pro-
ducer in Fig. 12, (pp. 45, 46).
The principal dimensions of the producer plant are as
follows:
Producer
Capacity, horse-power 250
Outside diameter feet 7.0
Inside diameter feet 6.5
Height feet 15
Area of fuel-bed square feet 38.5
Diameter of gas delivery pipe inches 22
Type of feed, Bildt automatic continuous feed.
Economizer
Diameter feet 3
Height feet .... 16 . 5
Number of 7 -inch tubtt... 6
44 ILLINOIS ENGINEERING EXPERIMENT STATION
Scrubber
Diameter .feet ... 8
Height feet. . . . 20
Material used in scrubber, gas-house coke.
Tar extractor
Speed, revolutions per minute , 1500
Purifier
Length of sides feet 8
Height feet.... 3.25
Material used in purifier, oxidized iron filings and wood shavings.
Gas holder
Diameter feet 20
Height feet. ... 13
Capacity cubic feet. . . 4000
27. The tests were conducted alternately on the two pro-
ducers, one being charged while the other was in operation. The
schedule adopted involved two sixty-hour runs per week. The
first eight or twelve hours of each test were used for bringing the
fuel bed to a uniform condition. During this preliminary run-
ning, observations were made as in the regular tests, but the
record data include only the last 48 or 50 hours, when the run-
ning conditions were maintained as uniform as possible. Special
attention was directed to the accurate measurements of the coal
actually used and charts and checking devices were introduced
for this purpose.
Owing to the lack of reliability in the operation of the gas
engine, many of the tests made at the beginning of the series
were only of a few hours' duration; later, however, no difficulty
was experienced in starting the engine and continuing it in opera-
tion for a period of 120 hours. During this time two different
coals were tested. Altogether 30 tests were made involving the
use of 23 different samples of Illinois coal.
28. Results of the tests. The more important observed and
calculated results of the tests are given in Table 11. Column 1 of
this table is the laboratory number of the test, Column 2 the
U. S. G. S. number of the sample tested and Column 3 the size of the
coal tested. The proximate analyses of the coal as fired are given
in Columns 4 to 8 and the heating value in B. t. u. per pound of
dry coal is given in Column 4. The brake horse-power given in
Column 10 is the power delivered by the gas engine. Column 11
is the cubic feet of gas delivered by the producer per hour, in
terms of standard gas, that is, gas at atmospheric pressure and
60 F. temperature. Column 12 is the calorific value of the gas
expressed in B. t. u. per cubic foot of standard gas. Column 13
FUEL TESTS WITH ILLINOIS COAL
45
QQ
46
ILLINOIS ENGINEERING EXPERIMENT STATION
FIG. 12 ELEVATION SHOWING GENERAL ARRANGEMENT OF
PRODUCER-GAS PLANT (Prof. Paper 48, p. 983)
FUEL TESTS WITH ILLINOIS COAL
47
-9S.IOH a^Jg *sd patnns
-UOQ IOO -JQ
IOQ ^JQ jo panod iad
st?o at pgaiBiaoo -n * -g
IBOQ AJQ jo panod igd
s^o pj^puBig jo 399J ojqno
jo :jooj oiqno aad -n ^ g
anon J9d SBQ
pa^pa^^s JO 589J oiqno
jo panod J9d - n
5090 jgj '
Proximate Analysi
of Coal as Fired,
per cent
qsy
ox -S.--D - s -a
os T* TJ. to oo tt cs < i- o ec -<N^- . ec r- * ^ oo m <o o o - eo ~* * -o
oo mow to e> o t^ t--* oo^* 01 ao o -osor-^ooi-imosooo*Jme*-*
ill i
o o o o M oo aooo IN oo
-?? ?i -M ?!
OS 05 CD r- t^ 00 i-iOO" t-t-0(M eCOOO>0^0'-05C<5COiOICffC5
<ncn . Q M fl ^ 3 G
T3; :::: gc3 . 3 T 1 & ?
48
ILLINOIS ENGINEERING EXPERIMENT STATION
is the cubic feet of standard gas per pound of dry coal. Column
14 is the B. t. u. contained in the gas per pound of dry coal fired.
This value divided by the heating value of the coal (Column 9)
equals the thermal efficiency of the producer. Column 15 is the
pounds of dry coal consumed by the producer per brake-horse-
power available for outside purposes.
In comparing the results of the producer tests as set forth in
Table 11, too much emphasis can not be given the fact that they
were subjected to absolutely no refinements. With the exception
of three coals one test only has been made on each kind and grade,
and the result of each test has, to a great extent, depended upon
the ability of the operator to discover the best methods of handling
a given coal within the 8 or 10 hours allowed preliminary to the offi-
cial test. Moreover, all tests were made on one type and in one
size of producer, a type designed primarily for anthracite coal,
and in carrying out the plan of the tests more effort was made to
develop the required power than to observe the proper relation
between the gas producing qualities of the coal and the area of
the fuel bed.
In spite of all these restrictions it is the opinion of those who
were in charge of the tests that certain general relationships have
100
90
80
70
60
50
3 40
30
fe 20
o 10
10
1(1
18
12 14
Ash Per Cent
FIG. 13 CUBIC FEET OF GAS PER POUND OF COAL AS AFFECTED
BY PER CENT OF ASH IN DRY COAL
FUEL TESTS WITH ILLINOIS COAL 49
been fairly well established. They may be subject to modification
in the light of future investigations, but the conclusions to be
drawn from them are sufficiently significant for presentation.
29. Efficiency as affected ~by ash in the coal. The cubic feet of
gas delivered by the producer per pound of coal fired is, perhaps,
the most convenient measure of efficiency. Referring to Column
13, Table 11, it will be seen that in general as the ash in the coals
increases this quantity decreases. The exact relation for all
tests made at full load is shown graphically in Fig. 13. In this
figure, cubic feet of standard gas per pound of dry coal is plot-
ted against ash expressed in per cent of dry coal. The average
line is drawn so as to include as many of fche plotted points as
possible. It shows that when the coal contains 8 per cent ash
the output of the producer is 67 cubic feet per pound of dry coal
fired and that when ash is 20 per cent the output is decreased to
50 cubic feet.
30. Efficiency as affected by calorific value of the coal. The
cubic feet of gas per pound of dry coal plotted against B. t. u.
per pound of dry coal for all tests made at full load is shown in
Fig. 14. Since the heating value of Illinois coal is very nearly
inversely proportional to the ash content the relation shown is
merely a restatement of the facts brought out in Fig. 13. The
points, however, fall in better alignment. It appears from
the curve that the output of gas in cubic feet per pound of coal
increases from 49 when the calorific value is 1 1000 B. t. u. per
pound of dry coal, to 65 when the calorific value is 13000. Fig. 15
shows the efficiency expressed in per cent plotted against the
heating value of the coal. Here the same rise in efficiency is
again shown. The average value at 11000 is 58 per cent and at
13000 it is 76 per cent.
50
ILLINOIS ENGINEERING EXPERIMENT STATION
100
o 90
O
80
7
-
B 10
o
11000
12000 13000
B. t, u. per pound of Coal
14000
FIG. 14 CUBIC FEET OF GAS PER POUND OF COAL, AS AFFECTED
BY CALORIFIC VALUE OF THE COAL
100
W 10
11000
12000 13000
B. t. u. per pound of Coal
14000
FIG. 15 EFFICIENCY OF PRODUCER AS AFFECTED BY CALORIFIC
VALUE OF THE COAL
FUEL, TESTS WITH ILLINOIS COAL
51
31. A comparison of Illinois coal with other bituminous coals.
A condensed summary of the more important items relating to
Illinois coals compared with those relating to all other bituminous
coals tested, is presented in Table 12. The average values given
TABLE 12
A COMPARISON OF ILLINOIS COAL WITH BITUMINOUS COALS
FROM OTHER STATES FOR GAS PRODUCER SERVICE
Average of
Tests with
111. Coal
Average of
All Tests
with Bitum-
inous Coal
Composition of fuel, per cent:
Moisture
10 84
6 82
Volatile matter . .
33 06
33 06
Fixed carbon
44 06
49 80
Ash
12 04
10 32
Sulphur
3 15
2 41
B. t. u, per pound of dry coal ...
12000
13150
Composition of gas, volume per cent:
Carbon dioxide . . .
9 60
9 84
Oxygen . . .
03
04
Nitrogen
56 81
55 60
Hydrocarbons
3 21
3 30
Carbon monoxide . ...
18 31
18 28
Hydrogen
12 01
12 90
B. t. u, per foot of standard gas
146 5
152 1
Cubic feet of standard gas per pound of dry coal
59 1
64 7
Pounds of dry coal per brake horse power, hour
1.36
1 26
are computed only from tests in which the producer was operated
at its rated capacity. It will be noted that while the analysis
shows that the Illinois coal contains 4 per cent more moisture and
2i per cent more ash the quality of the gas produced is but
slightly inferior. Thus the heating value is 146.5 B. t. u. per
foot of standard gas when Illinois coal is used and 152.1 when
other bituminous coal is used. The output of gas, measured in
cubic feet per pound of dry coal, is 59.1 in the one case and 64.7
in the other. Comparing the efficiency at the engine it will be
seen that it requires 1.36 pounds of Illinois coal to develop a
horse- power and 1.26 pounds when other bituminous coals are
used. This comparison is by no means unfavorable and consid-
ering the lower selling prices which prevail for Illinois coals the
very slight difference in efficiency is almost insignificant.
32. Relative results of steam and producer-gas tests. From
theoretical considerations it may easily be shown that it is pos-
sible for the gas engine to utilize a much larger amount of the
ILLINOIS ENGINEERING EXPERIMENT STATION
RELATIVE AMOUNT OF ILLINOIS COAL USED BY STEAM AND
PRODUCER PLANT
POUNDS PER BRAKE HORSE-POWER HOUR
OQ
Steam Plant
Producer Plant
Ratio
*7A
11C
7C
27
*7B
190
21
*23B
*6B
4
9B
26
8
3
23A
29B
22A
16
15
14
13
18
30
25
10
24B
19B
11A
*11D
*11D
| i
01234
* No producer test.
FIG. 16 RELATIVE COAL CONSUMPTION IN GAS AND STEAM PLANTS.
FUEL TESTS WITH nJ#K#ISr-@OAI/- J ' J 53
heat supplied than the steam engine. The results of the present
tests show how much of this saving is realized in practice.
The ratios of the total coal per brake horse- power hour re-
quired by the steam plant and producer gas plant under full
load conditions are presented in Fig. 16. The values representing
producer plant performance are those of Column 15, Table 11,
and those representing steam plant performance are calculated
from those of Column 25, Table 8, allowing 85 per cent as the
efficiency of the dynamo. It will be seen that the maximum ratio
is 3.13 and the minimum 1.50 while the average is 2.61.
54 l iLilNbW ENGINEERING EXPERIMENT STATION
UNITED STATES GEOLOGICAL SURVEY PUBLICATIONS ON FUEL TESTING
The following publications, except those to which a price is affixed, can b^ obtained free
by applying to the Director. Geological Survey, Washington. D. C. The priced publications
can be purchased from the Superintendent of Documents, Government Printing Office, Wash-
ington. D. C.
Jhdletin No. 261. Preliminary report on the operations of the coal-testing plant of the
Unit' d States Geological Survey at the Louisiana Purchase Exposition, in St. Louis, Mo., 1904;
E. W. Parker, J. A. Holmes, M. R. Campbell, committee in charge. 1905. 172 pp. 10 cents.
Professional Paper No. 48. Report on the operations of the coal-testing plant of the
United States Geological Survey at the Louisiana Purchase Exposition, St, Louis, Mo., 1904;
E. W. Parker, J. A. Holmes, M. R. Campbell, committee in charge. 1906- In three parts. 1492
pp. 13 pis $1.50.
Bulletin No, 290. Preliminary report on the operations of the fuel-testing plant of the
United States Geological Survey at St. Louis, Mo., 1905, by J- A. Holmes. 1906. 210 pp. 20 cents.
Bulletin No. 323. Experimental work conducted in the chemical laboratory of the United
States fuel-testing plant at St. Louis, Mo., January 1, 1905, to July 31, 1906. by N. W. Lord. 1907.
49pp.
Bulletin No. 3S5. A study of four hundred steaming tests, made at the fuel-testing plant,
St. Louis, Mo., 1904, 1905, and 1906. by L. P. Breckenridge. 1907. 196 pp.
Bulletin No. 332. Report of the United States fuel-testing plant at St. Louis, Mo.,
January 1, 1906, to June 30, 1907; J. A. Holmes, in charge. 1908. 299 pp.
Bulletin No. 334. The burning of coal without smoke in boiler plants: a preliminary re-
port, by D. T. Randall. 1908. 26 pp.
Bulletin No. 336. Washing and coking tests of coal and cupola tests of coke, by Richard
Moldenke, A. W. Belden. and G. R. Delamater. 1908. 76 pp.
Bulletin No. 339- The purchase of coal under Government and commercial specifications
on the basis of its heating value, with analyses of coal delivered under Government contracts,
by D. T. Randall. 1908. 27 pp.
Bulletin No- 343. Binders for coal briquets, by J. E. Mills. 1908. 56pp.
Bulletin No. 362. Mine sampling and chemical analyses of coals tested at the United
States fuel-testing plant, Norfolk, Va.. in 1907, by J. S. Burrows. 1908. 23 pp.
Bulletin No, 363. Comparative tests of run-of-mine and briquetted coal on locomotives,
by W. V. M. Goss. 1908. 57 pp.
Bulletin No. 366. Tests of coal and briquets as fuel in house-heating boilers, by D. T.
Randall. 1908. 44 pp.
Bulletin No. 368. Washing and coking tests of coal, by A. W. Belden, G. R. Delamater
and J. W. Groves. 1908. 53 pp.
PUBLICATIONS or THE ENGINEERING EXPERIMENT STATION
Bulletin No. 1. Tests of Reinforced Concrete Beams, by Arthur N. Talbot. 1904. (Out
of print.)
Circular No. 1. High-Speed Tool Steels, by L. P. Breckenridge. 1905. (Out of print.)
Bulletin No. 2. Tests of High-Speed Tool Steels on Cast Iron, by L. P. Breckenridge
and Henry B . Dirks. 1905. ( Out of print. )
Circular No. 2. Drainage of Earth Roads, by Ira O. Baker. 1906. (Out of print.)
Circular No. 3. Fuel Tests with Illinois Coal. (Compiled from tests made by the Tech-
nologic Branch of the U- S- G. S.. at the St. Louis, Mo., Fuel Testing Plant, 1904-1907, by L. P.
Breckenridge and Paul Diserens. 1909.
Bulletin No. 3. The Engineering Experiment Station of the University of Illinois, by
L. P. Breckenridge. 1906. (Out of print.)
Bulletin No. 4. Tests of Reinforced Concrete Beams. Series of 1905, by Arthur N.
Talbot. 1906.
Bulletin No. 5. Resistance of Tubes to Collapse, by Albert P. Carman. 1906. ( Out of
vrint.)
Bulletin No. 6. Holding Power of Railroad Spikes, by Roy I. Webber. 1906. (Out of
print.)
Bulletin No. 7. Fuel Tests with Illinois Coals, by L. P. Breckenridge, S. W. Parr and
Henry B. Dirks. 1906. (Out of print.)
Bulletin No. 8. Tests of Concrete: I. Shear; II. Bond, by Arthur N. Talbot. 1906. (Out
of print.)
Bulletin No. 9. An Extension of the Dewey Decimal System of Classification Applied
to the Engineering Industries, by L. P. Breckenridge and G. A. Goodenough. 1906.
Bulletin No. 10. Tests of Concrete and Reinforced Concrete Columns. Series of 1906, by
Arthur N. Talbot. 1907. (Out of print.)
Bulletin No. 11. The Effect of Scale on the Transmission of Heat through Locomotive
Boiler Tubes, by Edward C. Schmidt and John M. Snodgrass. 1907. (Out of print.)
Bulletin No. 12. Tests of Reinforced Concrete T-beams. Series of 1906. by Arthur N.
Talbot. 1907. (Out of print.)
Bulletin No. 13. An Extension of the Dewey Decimal System of Classification Applied
to Architecture and Building, by N. Clifford Ricker. 1907.
Bulletin No. 14. Tests of Reinforced Concrete Beams, Series of 1906, by Arthur N.
Talbot. 1907. (Out of print.)
Bulletin No. 15. How to Burn Illinois Coal without Smoke, by L. P. Breckenridge. 1908.
Bulletin No. 16. A Study of Roof Trusses, by N. Clifford Ricker' 1908.
Bulletin No. 17. The Weathering of Coal, by S. W. Parr, N. D. Hamilton, and W. F.
Wheeler. 1908. (Out of print.)
Bulletin No. 18. The Strength of Chain Links, by G. A. Goodenough and L. E. Moore. 1908.
Bulletin No. 19. Comparative Tests of Carbon, Metallized Carbon and Tantalum Fila-
ment Lamps, by T. H. Amrine. 1908.
Bulletin No. 20. Tests of Concrete and Reinforced Concrete Columns, Series of 1907, by
Arthur N. Talbot. 1908.
Bulletin No. 21. Tests of a Liquid Air Plant, by C. S. Hudson and C. M. Garland. 1908
Bulletin No. 22. Tests of Cast-Iron and Reinforced Concrete Culvert Pipe, by Arthur N.
Talbot. 1908.
Bulletin No. 23. Voids, Settlement and Weight of Crushed Stone, by Ira O. Baker. 1908.
Bulletin No. 24. The Modification of Illinois Coal by Low Temperature Distillation, by
S. W. Parr andC. K. Francis. 1908.
Bulletin No. 25. Lighting Country Homes by Private Electric Plants, by T. H.
Amrine. 1908.
Bulletin No. 26. High Steam-Pressures in Locomotive Service. A Review of a Report to
the Carnegie Institution of Washington. By W. F. M. Goss. 1908.
Bulletin No. 27. Tests of Brick Columns and Terra Cotta Block Columns, by Arthur N.
Talbot and Duff A. Abrams. 1909.
Bulletin No. 28, A Test of Three Large Reinforced Concrete Beams, by Arthur N.
Talbot. 1909.
Bulletin No. 29. Tests of Reinforced Concrete Beams: Resistance to Web Stresses,
by Arthur N. Talbot. 1909.
Bulletin No. 30. On the Rate of Formation of Carbon Monoxide in Gas Producers, by J.
K. Clement. L. H. Adams, and C. N. Haskins 1909.
Bulletin No, 31. Fuel Tests with House-heating Boilers, by J. M. Snodgrass. 1909.
Bulletin No. 32. The Occluded Gases in Coal, by S. W. Parr and Perry Barker. 1909.
3 *"? c
UNIVERSITY OF CALIFORNIA LIBRARY
Illinois
State
Reformatory
Print