f\
135
v.7
UC-NRLF
flbT 305
LIBRARY
OF THE
UNIVERSITY OF CALIFORNIA.
GIFT OF
Class
UNIVERSITY OF ILLINOIS BULLETIN
Vol. HI
AUG. 15, 1906
[Entered at Urbana. Illinois, as second-class matter,
No. 22
FUEL TESTS WITH ILLINOIS COALS
L. P. BRECKENRIDGE
S. W. PARR
H. B. B1RKS
BULLETIN NO. 7 OF i ' ] :" VERSITY OF ILLINOIS
ENGINEERING EXPERIMENT STATION
URBANE
pi . - , . D •"• FHE U* ' HSTTY
i of the Uni-
f Illinois. Thi-
• ie Board of Trustees
purpose of the Station to
and
to s e to professional engineers and to
interests of tl
the Em, riment Station is
nts of the College of En-
-titute ti ion Staff, and with the Di-
to be in'!.
'< on of the S i
,-y a Fe! iuate work. nies by
•ing, but
n g to the Station Corps.
s of thc'sc invr published in the
A'ill record mostly the experiments of
of inv-; rs. Th- also be issued
from time 1 lie form of circulars, compilations giving
the results of the >f engirn • -?-ks,
istitutions and governme sting departments.
,e voluin ,- lumber at the top of the title page of the
covi 1,o the g( ons of the University of Illinois;
at the b<
ins o ir la • i.
• pies of bullet Of other information, add
nnee ins; : !: n ri menl -: • on, % : ' Illinois.
Tit
UNIVERSITY OF ILLINOIS
ENGINEERING EXPERIMENT STATION
BULLETIN No. 7 AUGUST 1906
FUEL 'TESTS WITH ILLINOIS COALS
BY
L. P . BRECKENRIDGE, . . PROFESSOR OF MECHANICAL ENGINEERING
S. W. PARR, PROFESSOR OF APPLIED CHEMISTRY
H. B. DIRKS, ASSISTANT IN MECHANICAL TECHNOLOGY
During the last ten years a considerable number of boiler
trials have been made at the University of Illinois. Many of these
have been made under the boilers in the power plant of the Uni-
versity. Still other trials have been made with boilers in use at
the plants in neighboring cities. In some instances experts rep-
resenting several special stoker and furnace companies have been
present at these trials and operated the devices in which they
were interested. For the most part, however, the tests have been
made in order to instruct students in the usual methods of boiler
testing, and the boilers themselves have been operated under such
usual conditions as happened to obtain. In some of the earlier
tests all of the data relating to the heating value of the coals were
not obtained, and for such tests several items depending on these
values are necessarily omitted. While in most cases these tests
have not been made with the object of making a comparison of
coals or of appliances, nevertheless, it has seemed wise to publish
the results obtained and also to exhibit these results side by side
as they apply to various forms of furnaces, types of boilers or
kinds of coal. It is entirely probable that the results obtained are
equal to those generally obtained under the varying conditions of
plants using Illinois coals. Many more boiler trials have been
159348
2 ILLINOIS ENGINEERING EXPERIMENT STATION
made than are here reported, but only such are included in this
report as appear to be free from any indications of errors in
methods or results. For the purpose of this bulletin all of the
results of the tests have been carefully rechecked.
The work of the department of Applied Chemistry has not
only supplemented the work relating to boiler trials by furnish-
ing the composition and heating value of the coals used in these
trials, but it has also examined and tested a large number of Illi-
nois coals not yet tested under boilers. In connection with this
subject this department has perfected several new devices very
useful to chemists and engineers, designed for making the ordin-
ary determinations of the heating values and composition of coals.
The Parr calorimeter, one of these devices, has found ready sale
among the operators of many of the power plants of the country
as well as among the consulting chemists and fuel experts. It is
expected that a separate bulletin will soon be published setting
forth in detail many of the new methods which have been devel-
oped by this department, and giving the complete results of its
investigations relating to Illinois coals. It is hoped that the
tables of the chemical composition and heating values of Illinois
coals, which form a part of this bulletin, will furnish engineers
and manufacturers with useful information in this important field.
With the above somewhat general statement in explanation
of the character of this bulletin, it may now be advisable to refer
more in detail to the special features which are intended to be
brought out in the following pages.
BOILER TESTING
For many years engineers have been making "boiler tests"
with the object of finding out how many pounds of water in the
boiler could be evaporated with one pound of coal. In order that
the results of the tests might be comparable, it became evident
that some common method of making tests should be agreed upon
and also that the tests made should be reported in a uniform
manner. A committee of the American Society of Mechanical
Engineers recommended to that Society in 1899 a method of test-
ing boilers and also a method of reporting such tests. These
methods have been largely used since their recommendation at
that time. The many expert engineers who are to-day so familiar
with these methods will probably not be interested in the pages
PARR AND DIRKS
FUEL TESTS WITH ILLINOIS COALS 3
immediately following. Having in mind the owners and operators
of power plants as well as manufacturers and young technical
students, it has seemed worth while to present somewhat in detail
the following subjects:
(1) Observations to be made during a boiler trial.
(2) Appliances used during a boiler trial.
(3) Form of report, methods of operation and explanation of
computations.
I OBSERVATIONS TO BE MADE DURING A BOILER TRIAL
In the report of the committee of the American Society of
Mechanical Engineers,1 1899, on the revision of the standard code
for conducting steam boiler trials, two forms of report are submit-
ted, a Complete Form and a Short Form. These are both shown in
Section III, page 21. The observations necessary to complete
either of these forms are given in Table I. An explanation of
some of the methods used in obtaining these observations and
the forms used in recording them follow.
COAL, WATER AND ASH
The two fundamental points to be determined in every test of
a steam boiler or furnace, regardless of the special or specific
purpose of such test, are the pounds of water evaporated by the
boiler and the pounds of fuel necessary to produce such evapora-
tion. To determine these two points it is necessary to know the
number of pounds of water fed into the boiler and the pounds of
fuel fed into the furnace. The possibility of an error in either throws
doubt upon all the indications of the test. Each item, therefore,
should be ascertained in a manner that proves its own correctness,
and the records must be such that if errors are made, they will be
clearly exposed.
Coal. — The weight of the coal is best obtained by means of a
barrow or car with a capacity of 500 pounds. The car should be
loaded uniformly each time and weighed on platform scales in
front of the furnace. The total weight and the time of weighing
should be recorded in the log. From the car the coal should be
fired directly into the furnace and the weight of the separate
1 See Trans. A. S. M. E. Vol. XXI, p. 34.
4 ILLINOIS ENGINEEKING EXPERIMENT STATION
TABLE I
OBSERVATIONS TO BE MADE DURING A BOILER TRIAL
Short Trial
Standard Trial
Observations
1
1
Weight of water fed to boiler
2
2
Weight of coal as lired (sample)
3
3
Weight of ash and refuse (sample)
4
4
Moisture in coal
5
5
Steam pressure by gage
6
6
Force of draft: between damper and boiler
7
7
in furnace
8
in ash-pit
8
9
Temperature: of feed water entering boiler
9
10
of escaping gases from boiler
11
of external air
12
of tire-room
13
of steam
11
of feed water entering heater
15
of feed water entering economizer
16
of escaping gases from economizer
17
of gases in furnace
10
18
Moisture in steam by calorimeter
19
Analysis of flue gases
20
Smoke observations
21
Average thickness of fire, intervals of firing
charges and time of firing entered in the log. After the entire
car-load of coal has been fired, the weight of the empty car and
the time should be recorded. The sum of the separate charges
must then be equal to the difference in weight of the car when
loaded and empty. A convenient form for recording the coal fired
is shown in Form I. Prom each car-load of coal fired an average
sample of coal should be taken for moisture determination and
chemical analysis. The sample of course must be taken before
the coal is weighed and should be about two per cent of every car-
load, or about ten pounds. At the end of the test these samples
from the different cars are mixed, pounded into small sizes, and
then quartered until enough is left to fill a two-quart jar. The jar
should then be sealed, to prevent loss of moisture, and sent to
the chemist.
Feed Water. — The water fed to the boiler should be both weighed
and measured, as dependence upon measuring alone will introduce
errors due to uneven filling and variations in temperature; for the
latter, however, corrections may be made. The measuring tank
or preferably two tanks should be set on scales in such a position
that the water can be delivered directly into the suction or set-
tling tank as shown in Fig. 1. The measuring tanks should be
filled and emptied alternately, the time of each weighing to be
noted when the tank is empty, the tanks being designated as No.
1 and No. 2. In no case should a simple tally be recorded for
PARR°ANDBDIRKS]
FUEL TESTS WITH ILLINOIS COALS
Weighing and
Measuring TanH
FIG. 1 ARRANGEMENT OF TANKS AND SCALE FOR MEASURING
FEED-WATER FED TO BOILER
each tankful, as the liability of error is thereby increased. When
the boiler tested is of small capacity, one weighing tank will be
sufficient. A convenient form for recording the feed water meas-
urements is shown in Form II.
To guard against the loss of all data, due to accidents, it is
best to have coincident records of the water and coal fed to boiler.
For this reason it is well to have a float in the suction or settling
tank, and each time an entire car-load of coal has been fired> the
time on the feed water log should be recorded, also the height of
water in the boiler and in the settling tank. This will also pro-
vide a check on the uniformity of operations.
Ash. — The ashes and refuse should be weighed dry. The time
of each raking of the fire and cleaning of the ash-pit and the weight
ILLINOIS ENGINEERING EXPERIMENT STATION
FORM I
LOG OF BOILER TRIAL NO
Made at . .
Date
Boiler No
By
Fireman
COAL SHEET
COAL
COAL
COAL
DELIVERED
ON SCALES
FIRED
TIME
TO
AFTER
EACH
FUEL
SCALES
EACH FIRING
TIME
POUNDS
POUNDS
POUNDS
Moist coal consumed, pounds
Moisture in coal, per cent
Dry coal consumed, pounds
Wood consumed, pounds
Coal equivalent of wood (=wood x-4) Tb
j Total dry coal consumed including
1 wood equivalent, pounds
Total dry refuse, pounds
Total dry refuse, per cent
! Total combustible
DESCRIPTION OF FUEL
Commercial Name
Commercial size
Lumps, per cent
Small coal, per cent
Slack, per cent
%
Appearance of coal
j Record the times when fires
t cleaned
are
TESTS WITH ILLINOIS COALS
FORM II
LOG OF BOILER TRIAL NO.
Made at ,
Date
Bv.
Boiler No
Fireman
FEED WATER SHEET
TIME
WATER
DELIVERED
TO
FEED TANK
POUNDS
TKMP.
OF
WATER
IN
TANK
TIME
WATER
DELIVERED
TO
FEED TANK
POUNDS
TEMP.
OF
WATER
IN
TANK
REMARKS
•
Test began at
o'clock M.
•
Date
Test closed at
o'clock M.
Date,
8
ILLINOIS ENGINEERING EXPERIMENT STATION
FORM III
LOG OF BOILER TRIAL NO . .
Made at . .
Date
Boiler No
By
Fireman
PR
ESSUR
ES
TEMPI
iRATUI
IES
g
TIME
STEAM
GAGE
DRAFT
GAGE
BAROM-
ETER
1 BOILER
ROOM
EXTERNAL
AIR
FLUE
GASES
|
IFEED
WATER
STEAM
S , o o
Hg
REMARKS
Test began at
o'clock M.
Date,
Test closed at
o'clock M.
PARE°ANDBDIRKS] FUEL TESTS WITH ILLINOIS GOALS
FORM IV
LOG OF BOILER TRIAL NO
Made at . .
Date
Boiler No
By
Fireman
TIME
CALORIMETER
DRAFT
HEIGHT
OF WATER
IN TANK
gl3-
1^
Ȥ5
REMARKS
GAGE
PRESSURE
STEAM
DISCHARGE
OR CALORI-
METER
TEMP.
WATER
SEPARATED
OR CALORI-
METER
PRESSURE
BETWEEN
DAMPER
AND
BOILER
IN
FURNACE
Be
Hw
/n
•<
i
10 ILLINOIS ENGINEERING EXPERIMENT STATION
FORM V
Made
Date
at
Rv..
Boile
r No . Fireman
FLUE-GAS SHEET
TIME
C02
02
CO
HYDROGEN
AND
HYDROCAR-
BONS
TOTAL,
REMARKS
FUEL TESTS WITH ILLINOIS COALS 11
of ash removed should be recorded in the same log as the weight
of coal, Form I. A representative sample of ash should be taken
at every cleaning and saved in order to determine the principal
characteristics of the ash, a proximate analysis giving the actual
amount of incombustible material being made of each sample.
GENERAL OBSERVATIONS
Although the main points to be determined in a boiler trial
are the weight of water evaporated and the amount of fuel burned,
the general observations of pressures, temperatures, etc., under
which this evaporation takes place and which tend to secure the
accuracy of these two measurements must not be overlooked. It
is necessary that all available data be obtained and recorded in the
log for use in making comparisons. The value of the observation
will depend primarily upon its correctness and the greatest care
should be exercised in obtaining and recording observations. Too
often the observer is guided by personal opinion and former
readings, and the value of the observation as an indication of some
specific occurrence is entirely lost.
All general observations should, as nearly as possible, be
taken at the same instant, the exact time in all cases being recorded
in the log. As a rule all observations should be recorded in dupli-
cate, this being necessary especially where several persons are
concerned with the results. Duplicates are easily obtained by
placing carbon copying paper below the original log. The dup-
licates are then obtained as the results are originally recorded.
Forms for recording the general observations are shown in
Forms III to V.
For convenience it is best to have the log sheets tacked to a
board, which may be suspended on the wall at some convenient
point. This avoids the accumulation of dust and dirt when the
sheets are lying around unattached in a horizontal position.
Sufficient time should elapse between temperature measure-
ments if only one thermometer serves for taking several observa-
tions, in order to allow the thermometer to assume the new tem-
perature. TvVhere the range of temperature is large, however, this
should never be practised, and it will be preferable in most cases
to take only the most important of the readings, being certain of
its correctness.
12
ILLINOIS ENGINEERING EXPERIMENT STATION
Determinations of the moisture in the steam are necessary to
make corrections in the amount of water evaporated, and should
be made at regular intervals and entered in the log.
The analysis of the flue gases is important as it indicates to
some extent the progress of combustion in the furnace. Notwith-
standing, the general use of this analysis is still very limited, al-
though in some instances a record of the CO in the flue gases is
regularly kept. The value of the analysis consists in its being
an indication of the amount of excess air being used. The flue
gas to be analyzed should be an average sample taken con-
tinuously over a considerable period of time. This is necessary
as the composition of the gases varies from minute to minute.
Under ordinary conditions an analysis every half-hour is sufficient;
special readings, however, may be taken more often. The ap-
paratus for sampling will be explained in the following section.
II APPLIANCES USED DURING A BOILER TRIAL
Since the corrections to be applied to the weights of fuel and
water fed to the boiler are dependent on the general observations,
the appliances necessary for their determination must be consid-
ered. The correctness of the observations will depend primarily
on the instruments used and their location. In the following para-
graphs these are discussed to some extent.
DESCRIPTION OF APPLIANCES
A list of the apparatus necessary to take the observations
given in Section I is shown in Table II. The apparatus required
TABLE II
APPLIANCES FOR OBSERVATIONS GIVEN IN TABLE I
Short Trial
Standard Trial
Appliances
1
1
Measuring and suction tanks for measuring water
2
2
Platform scales for weighing water
3
3
Car or barrow for handling coal
4
4
Platform scales for weighing coal
5
5
Standard calibrated steam gage
6
6
Draft gages, U tubes or otherwise
7
7
Thermometers according to observations made
8
8
Flue gas thermometer
9
Pyrometer for furnace temperatures
9
10
Throttling or separating calorimeter
11
Orsat apparatus for flue gas analysis
12
Smoke charts
° ANDRmRKs]
FUEL TESTS WITH ILLINOIS COALS
13
in the determination of the weights of coal and water was discussed
in the previous section and needs no explanation other than that
the scales used should be calibrated so that a correction may be ap-
plied if necessary. The suction tank should also be calibrated so
that the contents of the tank are known for all positions of the float.
For measurement of the steam pressure an ordinary steam
gage calibrated by comparison with a standard gage or other
means will suffice. A good recording steam gage carefully ad-
justed and compared at frequent intervals with the steam gage
provides a good check. Various forms of draft gages are used to
determine the draft pressure. The ordinary U tube is the most
common form and gives very satisfactory results. A gage of the
type shown in Pig. 2 has been extensively used at the University
and gives results which can be read with greater accuracy than
the U tube.
FIG. 2 DRAFT GAGE
In the choice of thermometers care should be taken that the
range of readings will fall within that of the thermometer. Where
thermometers are likely to be handled constantly, a metal casing
is desirable. Where temperatures within a pipe are required, as
in steam or water pipes, thermometer cups, as shown in .Fig. 3
will need to be used.
Either mercury or a heavy cylinder oil may be used in these
cups; the former, however, is preferable both for cleanliness and
accuracy. For the measurement of flue gas temperatures a spe-
cial mercury thermometer is used, reading up to 1000° F., with
nitrogen compressed above the mercury.
The thermometer should be calibrated from time to time to in-
sure its correctness. The location of the thermometer will be dis-
cussed in the following section.
14 ILLINOIS ENGINEERING EXPERIMENT STATION
Thermometer
Mercury
bath ~
FIG. 3
THERMOMETER CUP, USED TO OBTAIN TEMPERATURES
WITHIN A PIPE
The measurement of furnace temperatures is very difficult,
and no especial form of pyrometer has proved to be entirely satis-
factory. The Wanner optical pyrometer is being used at the Gov-
ernment Coal-Testing Plant at St. Louis, and seems to be giving
fair results.
B-/n holes Gfr///eaf
/7e//c0//y a/ong
FIG. 4 SAMPLING NOZZLE FOR STEAM CALORIMETER
For determining the moisture in the steam, as long as the
moisture remains below three per cent, any one of several forms
of calorimeters may be used with good results. Above this point,
all calorimeters are inaccurate, owing to the inability to obtain an
average sample of the steam. The sampling nozzle, Fig. 4, should
be made of i-in. pipe, and should extend across the diameter of
BRECKENBIDGB. ~]
PABB AND DIBKS J
FUEL TEST8 WITH ILLINOIS COALS
15
the steam pipe to within half an inch of the opposite side, being
closed at the end, and perforated with not less than twenty i-in.
holes equally distributed along and around its cylindrical surface,
but none of these holes should be nearer than i inch to the inner
side of the steam pipe. The calorimeter and pipe leading to it
should be well covered with felt. When a separating calorimeter
with attached gage for determining the amount of steam passing
through the calorimeter is used, such gage should be calibrated by
taking readings over twenty minutes in length, and condensing
the steam passing through the calorimeter during that time, the
weight of condensed steam being compared with the indication on
the gage. This should be repeated for the entire range of the gage.
Superheating should be determined by means of a thermometer
placed in a mercury well, inserted in the steam pipe.
Hue
-/n. gas
One for every
. eross-
of f/ue
/ron recever
box
-/n pipe
FIG. 5 FLUE GAS SAMPLER. ADVISED IN THE A. S. M. E. STANDARD CODE
FOR CONDUCTING STEAM BOILER TRIALS
For determining the composition of the flue gases a sampling
tube for drawing the sample of gas from the flue is necessary, also
apparatus for analyzing the gas. There has been a great diver-
sity of opinion regarding the method to be used in obtaining the
16
ILLINOIS ENGINEERING EXPERIMENT STATION
FIG. 6 ORSAT APPARATUS FOR ANALYZING FLUE GAS
sample, due probably to the varying conditions in different boiler
settings and at different points in the same flue. In the trials
carried on by the United States Geological Survey at St. Louis,
both the sampler advised in the A. S. M. E. code, Fig. 5, and an
ordinary pipe closed at the end and perforated with holes equally
spaced along its entire length have been used. The results indi-
cate the advisability of using the latter, and it has been adopted
for use in all future trials. To get a uniform flow through all the
perforations, they are made of such size and number that the sum
of the areas of the perforations is less than the cross sec-
tional area of the sampling tube. The Orsat apparatus is the one
mostly used for analyzing the flue gases, as it is simple in opera-
tion, and with a little care gives reliable results. To insure the
PBABBCANDBD?BK91 FUEL TEST8 WI
17
No. 1.
No. 2.
No. 4.
No. 3.
FIG. 7 THE RINGELMAN SCALE FOR GRADING THE DENSITY
OF SMOKE
18 ILLINOIS ENGINEERING EXPERIMENT STATION
total absorption of the various gases, care must be taken that the
absorbing solutions are in good condition, and they should there-
fore be renewed from time to time. If the flue gas is to be col-
lected over water, a saturated salt solution should be used, as
water has a tendency to retain some of the CCte when a consider-
able quantity is present, and to give it up later when there is a
smaller quantity of this gas, thus causing errors in the results.
Fig. 6 shows the type of Orsat apparatus generally used.
If determinations of the relative density of the smoke are to
be made during the trial, the Ringelman smoke charts shown in
Fig. 7 may conveniently be used. These are placed in a horizon-
tal row about fifty feet from the observer, and as nearly as con-
venient in line with the chimney. At this distance the lines become
invisible and the cards appear as different shades of gray. The
observer by glancing from the chimney to the cards determines
which card most nearly corresponds to the color of the smoke and
makes a record accordingly.
LOCATION OF APPLIANCES
Of prime importance in taking observations is the location of
the apparatus used. On account of the variation in different types
of boiler settings it will always be necessary to describe clearly
in the report of the test the location of all apparatus. This is best
done by indicating on drawings or diagrams their position on the
setting.
Feed Water Temperature. — As the methods used in supplying
feed water to a boiler vary, so does also the location of the ther-
mometer for the temperature measurement of such feed water. If
an injector be used, it should receive steam directly through a
covered pipe from the boiler being tested, and the temperature of
the feed water should in this case be taken from the supply tank
furnishing the water to the injector. It is here assumed that the
heat of the steam operating the injector is returned to the boiler
from which it was taken, so that the supply pipe between the boiler
and injector, if long, should be covered to prevent radiation. If a
pump be used for feeding the boiler, the temperature of the feed
water should be taken by a thermometer in the discharge pipe as
near the boiler as possible. If this is done, the water may or may
not be pumped through a feed water heater after leaving the pump.
BBECKENBIDGE
PAKB AND DIRKS
s] FUEL TESTS WITH ILLINOIS COALS 19
It is always essential that the heat carried into the boiler by the
feed water should be known, and it is well to record its temperature
before and after it passes through any kind of heater or economiz-
er in order that the effect of such device may be given proper credit.
The location of thermometers for the determination of boiler
room and external air temperatures should be such that drafts or
heat rays will be avoided. The flue gas temperature should be
taken at a point where the gases leave the boiler and pass into the
breeching on their way to the stack. As the temperature in a
transverse section of the flue will vary, several readings should
be taken at different points of the same section. Observations of
the draft are usually made at several points of the setting. The
one between the damper and the boiler is, however, the more im-
portant, and should be taken at a point close to the flue gas ther-
mometer or possibly in the same transverse section. The force
of draft in furnace and ash-pit may be taken through the firing
and ash-pit doors, but is preferably taken through holes left in
the side walls. The calorimeter and the thermometer cup for de-
termining superheat should be attached to the vertical steam pipe
as it leaves the boiler. The sampling tube for the flue gas was
explained in the last section. It should be inserted in the flue at
the point where the flue gas temperature and draft are obtained.
Ill REPORT OF THE TRIAL
Forms. — The data and results of a boiler trial should be re-
ported in the manner given in Form VI, which is the complete
form advised by the Boiler Test Committee of the American Soci-
ety of Mechanical Engineers, Code of 1899. The items printed
in italics correspond to the items in the "Short Form" of report
recommended for commercial tests. For more elaborate trials the
code recommends that the full log of the trial be shown graph-
ically by means of a chart, Fig. 8.
20
ILLINOIS ENGINEERING EXPERIMENT STATION
02 91 91 fl 21 01 0 9 f"
SflNHOd 0001 HI NOIldWnSNOO "WOO
os gf ofr gs o« s« oz ci oi
SONOOd 0001 N| NOIidWnfiNOO U31VM
0022 0091 OOVI 0001
001 08 09 Ofr 02 0
13J Of
gajsj.no
pABB°ANDBDiBKsJ FUEL TESTS WITH ILLINOIS COALS 21
FORM VI
DATA AND RESULTS OF EVAPORATIVE TESTS
Arranged in accordance with the Complete Form advised by the Boiler Test Committee of the
American Society of Mechanical Engineers. Code of 1899.
Made by of boiler at to
determine
Principal conditions governing the trial
Kind of fuel*
Kind of furnace
State of the weather
Method of starting and stopping the test ("standard" or "alternate")
1. Date of trial
2. Duration of trial hours
Dimensions and Proportions
(A complete description of the boiler and drawings of the same if of unusual type, should be
given on an annexed sheet )
3. Grate surface width length area sq. f t-
4. Height of furnace in.
5. Approximate width of air spaces in grate in.
6. Proportion of air space to whole grate surface per cent
7. Water-heating surface sq. ft-
8. Superheating surf ace sq.ft.
9. Ratio of water-heating surface to grate surface — to 1
10. Ratio of minimum draft area to grate surface 1 to—
Average Pressures
11. Steam pressure by gage Ibs- per sq. in.
12. Force of draft between damper and boiler in. of water
13. Force of draft in furnace in. of water
14. Force of draft or blast in ash pit in. of water
Average Temperatures
15. Of external air deg.
16. Of flreroom deg.
J7. Of steam deg.
18- Of feed water entering heater deg.
19. Of feed water entering economizer deg.
20. Of feed water entering boiler deg.
21 . Of escaping gases from boiler deg.
22. Of escaping gases f rom economizer deg.
Fuel
23. Size and condition
24. Weight of wood used in lighting tire Ibs.
25. Weight of coal as fired " Ibs.
26. Percentage of moisture in coal per cent
27. Total weight of dry coal consumed • Ibs.
28. Total ash and refuse Ibs.
29. Quality of ash and refuse
30. Total combustible consumed Ibs.
31- Percentage of ash and refuse in dry coal per cent
Proximate Analysis of Coal
Of Coal. Of Combustible.
32. Fixed carbon percent percent
33. Volatile matter percent percent
34. Moisture percent
35. Ash per cent
100 per cent 100 per cent
Sulphur, separately determined per cent per cent
•"The items printed in italics correspond to the items in the "Short Form of Code.'
22
ILLINOIS ENGINEERING EXPERIMENT STATION
Ultimate Analysis of Dry Coal
Of Coal. Of Combustible.
37. Carbon (C) per cent per cent
38. Hydrogen (H) per cent per cent
39. Oxygen (O) per cent per cent
40. Nitrogen (N) per cent per cent
41. Sulphur (S) percent percent
42. Ash . .' per cent
100 per cent 100 per cent
43. Moisture in sample of coal as received per cent per cent
Analysis of Ash and Refuse
44- Carbon per cent
45. Earthy matter per cent
Fuel per Hour
46. Dry coal consumed per hour Ibs.
47. Combustible consumed per hour Ibs.
48. Dry coal per square foot of grate surface per hour Ibs.
49. Combustible per square foot of water-heating surface per hour Ibs.
Calorific Value of Fuel
50. Calorific value by oxygen calorimeter, per Ib. of dry coal B. T. U
51. Calorific value by oxygen calorimeter, per Ib. of combustible B. T. U
52. Calorific value by analysis, per Ib. of dry coal B. T. U
53. Calorific value by analysis, per Ib. of combustible B. T. U
Quality of Steam
54. Percentage of moisture in steam per cent
55. Number of degrees of superheating deg.
56. Quality of steam (dry steam —unity). (For exact determination of the factor
of correction for quality of steam see section on computation of results.) . .
Water
57. Total weight of water fed to boiler Ibs.
58. Equivalent water fed to boiler from and at 212 degrees Ibs.
59. Water actually evaporated, corrected for quality of steam Ibs.
60. Factor of evaporation Ibs.
61. Equivalent water evaporated into dry steam from and at 212 degrees. (Item
39 X Item 60.) Ibs.
Water per Hour
62. Water evaporated per hour, corrected for quality of steam Ibs.
63. Equivalent evaporation per hour from and at 21 2 degrees Ibs.
64. Equivalent evaporation per hour from and at 312 degrees per square foot of
water-heating surface Ibs.
Horse-Power
65. Horse-power developed, (34 H Ibs of water evaporated per hour into dry steam
from and at 212 degrees, equals one horse-power.) : H. P.
66. Builders' rated horse-power H. P.
67. Percentage of builders' rated horse-power developed per cent
Economic Results
68. Water apparently evaporated under actual conditions per pound of coal as fired.
(Item 57+Item 25.) Ibs.
69. Equivalent evaporation from and at 212 degrees per pound of coal as fired.
(Item&\+-Item 25.) Ibs.
70. Equivalent evaporation from and at 212 degrees per pound of dry coal.
(Item 61^-Item 27.) Ibs.
71. Equivalent evaporation from and at 212 degrees per pound of combustible.
( Item 61 -H Item 30.) Ibs.
(If the equivalent evaporation. Items 69, 70 and 71. is not corrected for the
quality of steam, the fact should be stated.)
Efficiency
72. Efficiency of the boiler; heat absorbed by the boiler per pound of combustible
divided by the heal value of one pound of combustible per cent
73. Efficiency of boiler, including the grate; heat absorbed by the boiler, per pound
of dry coal, divided by the heat value of one pound of dry coal per cent
BBECKENBIDGE. ~]
PARK AND DIBKSj
FUEL TESTS WITH ILLINOIS COALS
23
Cost of Evaporation
74. Cost of coal per ton Ibs. delivered in boiler room ; $
75. Cost of fuel for evaporating 1 ,000 Ibs of water under observed conditions $
76. Cost of fuel used for evaporating 1 ,000 Ibs. of water from and at 212 degrees $
Smoke Observations
77. Percentage of smoke as observed per cent
78. Weight of soot per hour obtained from smoke meter ounces
79. Volume of soot per hour obtained from smoke meter cu. in.
Methods of Firing
80. Kind of firing (spreading, alternate, or coking)
81. Average thickness of fire
82. Average intervals between firings for each furnace during time when fires
are in normal condition
83. Average interval between times of levelling or breaking up
Analyses of the Dry Gases
84. Carbon dioxide (CO2) per cent
85. Oxygen (O)
86. Carbon monoxide (CO)
87. Hydrogen and hydrocarbons
«8. Nitrogen (by difference) (N)
100 per cent
HEAT BALANCE, OB DISTRIBUTION OF THE HEATING VALUE OF THE COMBUSTIBLE
TOTAL HEAT VALUE of 1 lb. of Combustible B. T. U.
B.T.U.
Per Cent
1. Heat absorbed by the boiler = evaporation from and at 212 degrees
per pound of combustible X 965 7.
2. Loss due to moisture in coal = per cent of moisture referred to corn-
bustible-MOG X [ (21-2— 0+966+0. 48 (T — 212) ] (t — temperature
of air in the boiler room, T = that of the flue gases)
3. Loss due to moisture formed by the burning of hydrogen = per cent
of hydrogen to combustible- 100 X 9 X [ (212-^+966+0. 48 ( 3T-212) J
4.* Loss due to heat carried away in dry chimney gases = weight of gas
per pound of combustible X 0 .24 X ( T—t) .
CO
5,t Loss due to incomplete combustion of carbon =
per cent C in combustible
100
C02
CO
Loss due to unconsumed hydrogen and hydrocarbons, to heating the
moisture in the air, to radiation, and unaccounted for. (Some of
these losses may be separately itemized if data are obtained from
which they may be calculated.)
Totals...
100.00
*The weight of gas per pound of carbon burned may be calculated from the gas analyses as
follows:
11CO2 +80 +7 CO + (N)
Dry gas per pound carbon = — — , in which CO2, CO, O, and N are the
3 (CO2 + CO)
percentages by volume of the several gases. As the sampling and analyses of the gases in the
present state of the art are liable to considerable errors, the result of this calculation is usually
only an approximate one. The heat balance itself is also only approximate for this reason as
well as for the fact that it is not possible to determine accurately the percentage of unburned
hydrogen or hydrocarbons in the flue gases.
The weight of dry gas per pound of combustible is found by multiplying the dry gas per pound
of carbon by the percentage of carbon in the combustible, and dividing by 100.
+CO2 and CO are respectively the percentage by volume of carbonic acid and carbonic oxide
in the flue gases. The quantity 10,150= Number of heat units generated by burning to carbonic
acid one pound of carbon contained in carbonic oxide.
24 ILLINOIS ENGINEERING EXPERIMENT STATION
STARTING AND STOPPING THE TEST
Standard Method. — Steam being raised to the working pres-
sure, remove rapidly all fire from the grate, close the damper,
clean the ash pit, and as quickly as possible start a new fire with
weighed wood and coal, noting the time and the water level while
the water is in a quiescent state, just before lighting the fire. At
the end of the test, remove the whole fire, which has been burned
low, clean bhe grates and ash-pit, and note the water level when
the water level is in a quiescent state, and record the time of
hauling the fire. The water level should be as nearly as possible
the same as at the beginning of the test. If it is not the same a
correction should be made by computation, and not by operating
the pump after the test is complete.
Alternate Method. — The boiler being thoroughly heated by a
preliminary run, the fires are to be burned low and well cleaned.
Note the amount of coal left on the grate as nearly as it can be
estimated; note the pressure of steam and the water level. Note
the time and record it as the starting time. Fresh coal, which
has been weighed, should now be fired. The ash-pits should be
thoroughly cleaned at once after starting. Before the end of the
test the fires should be burned low, just as before the start, and
the fires cleaned in such a manner as to leave a bed of coal on the
grates of the same depth and in the same condition as at the start.
When this stage is reached, note the time and record it as the
stopping time. The water level and steam pressure should pre-
viously be brought as nearly as possible to the same point as at
the start. If the water level is not the same as at the start,
a correction should be made by computation, and not by operat-
ing the pump after the test is completed.
The two methods given above for starting and stopping the
test are taken from the A. S. M. E. Code for conducting steam
boiler trials. When the alternate method is used, several precau-
tions regarding the observations are necessary. The time of
starting and stopping should be noted when the smallest amount
of fuel is on the grate, and when it is in the most burned- out con-
dition, i. e. , just before firing fresh coal after cleaning, and when
the water level is in its most quiet condition and the least raised
by ebullition. This condition of fire and of water level can be
duplicated immediately after cleaning the fire, but there is no cer-
tainty of duplication of any condition when there is a bright fire
FUEL TESTS WITH ILLINOIS COALS 25
and consequent rapid steaming. If the water level is noted at
the starting of the test when it is raised by a bright fire, and at
the end of a test when it is depressed by the stoppage of violent
ebullition or of rapid circulation due to the cooling of the fire, the
boiler will be credited with more water than was really evapo-
rated. As such a fall in water level is easily produced by open-
ing fire doors and checking draft, it should be guarded against
especially when using bituminous or flaming coals. The greatest
care should also be taken that the bed of coal at the end does not
contain more waste material, which belongs to the ash, than it
did at the beginning.
COMPUTATION OF RESULTS
On account of the variations in the types of boilers and fur-
naces, no specific directions can be given for the measurement of
grate surface, height of furnace and other furnace proportions.
The heating surface should be computed from the surface of
shells, tubes and fire-boxes in contact with fire or hot gases. The
outside diameter of water tubes and the inside diameter of fire
tubes should be used in this computation. All surfaces below the
mean water level which have water on one side and products of
combustion on the other are to be considered as water- heating
surface, and all surfaces above the mean water level which have
steam on one side and products of combustion on the other are to
be considered as superheating surface.
The following directions show how some of the results to be
derived from a boiler trial may be obtained. The calculation of
other items is self-evident.
Item 26, the moisture in the coal, should be obtained by the
chemist by drying the sample collected during the test, for one
hour in a sand or air bath at a temperature between 240° and
280° F. Sometimes the moisture is obtained by drying a known
quantity of the coal above the boiler; however, if this method is
used, it should be so stated in the report. The first method is
always to be preferred. (See Section VI, page 48).
Item 27=Item 25 X (100— Item 26)
Item 30=Item 27X(100-Item 42)-(Item 28Xltem 44)
As this is dependent upon the ultimate analysis of the coal,
which is not always available, the following may be used:
Item 30=Item 27-Item 28
OF THE
UNIVERSITY
26 ILLINOIS ENGINEERING EXPERIMENT STATION
The latter, however, is in error, due to the unaccounted- for
ash passing over the bridge wall.
Item 51=Item 50 -5- (100— Item 42)
or =Item 50-Kltem 27— (Item 28Xltem 45)]
in which the former depends again upon the ultimate analysis of
the coal.
Items 52 and 53—14,600 0+62,000(11—^-) +4,000 S,
o
in which C, H, O and S refer to the proportions of carbon, hydro-
gen, oxygen and sulphur respectively, as determined by the ulti-
mate analysis.
H— 1146.6— 0.48 (T— 212)
Item 54=1 00 X
or =100 X
L
Ibs. of moisture separated
Ibs. of steam-fibs, of moisture separated
in which H=total heat and Lr=latent heat per pound of steam at
the pressure in the steam pipe, and T=temperature of the throt-
tled and superheated steam in the calorimeter. The first formula
applies to throttling and the second to separating calorimeters.
Item 55 should be taken as the difference between the read-
ing of the thermometer for superheated steam and the readings
of the same thermometer for saturated steam at the same pres-
sure as determined by a special experiment and not by reference
to the steam tables.
Item 5tS=100— Item 54
For the exact determination of the factor of correction for
quality of steam we have the following:
For wet steam, F=Q-hP(^ — =r-), and
±1 — Ji
For superheated steam, F=l+^— ^, in which
±1 — Ji
F = factor of correction
Q = quality of steam
P = per cent of moisture in steam
K = degrees of superheating in steam
H = total heat of the steam due to the steam pressure
Ti= total heat in the water at the temperature due to the
steam pressure
Ji= total heat in the feed water due to the temperature
Item 59 = Item 57 X Item 56
FUEL TESTS WITH ILLINOIS COALS 27
TT _ "U
Item 60=;r— -7,, in which H and h are respectively the total
i
heat in the steam of the average observed pressure and in water
of the average observed temperature of the feed. This item may
usually be obtained directly from steam tables giving the factors
for different pressures and feed water temperatures.
Item 61 = Item 59 X Item 60
Item 62 = Item 59^- Item 2
Item 63 = Item 61-*- Item 2
Item 64 = Item 63-^ Item' 7
Item 65 = Item 63-^34.5
This is held to be equivalent to 30 pounds of water evaporat-
ed from 100° F. into dry steam at 70 pounds gage pressure. The
former equals 33,317 B. T. U. per hour and the latter 33,305
B. T. U. per hour.
Item 66. — This item should give besides the rated horse-
power the basis (square feet of heating surface) upon which this
rating is made.
Item 67 = Item 65^- Item 66
The necessary computations for economic results and effi-
ciency, items 68 to 73, are indicated in the form of report.
IV REPORT OF BOILER TESTS WITH ILLINOIS COALS
The following tables contain a summary of the results of
boiler tests made by the department of Mechanical Engineering
at the University of Illinois. For the most part these tests have
been made, as stated in the introduction, for purposes of instruc-
tion in the method of boiler testing, although a considerable num-
ber were made for investigational purposes or as thesis work.
As a rule, they have been conducted under the direct supervision
of a member of the instructional staff of the department, but at
times when experiments were being made with special applian-
ces, the representative of the company interested was present to
take charge of the test.
COALS TESTED
The coals used in these tests were mostly those purchased
under the yearly contracts of the University. In a few cases,
special coals were purchased, while other tests were made on
28 ILLINOIS ENGINEEBING EXPERIMENT STATION
coals sent to the University by various coal companies and manu-
facturing concerns to determine the evaporative efficiency or
their behavior on various kinds of stokers.
35 coals were tested, representing 14 counties of Illinois.
These are given in the list below together with the commercial
size of the coal.
County Town Commercial Size
\ Christian Pana Lump
2 Christian Pana Slack
3 Christian Pana Srceenings
4 Coles Paradise Lump
5 Gallatin Junction Pea
6 Macon Niantic Nut
7 Macoupin Mt- Olive Lump
8 Madison Glen Carbon Lump
9 Marion Odin Lump
10 Marion Odin Pea
11 Marion - Odin Slack
12 McLean. Bloomington Lump
13 McLean Coif ax Lump
14 Menard Athens Lump
15 Perry Du Quoin Lump
16 Perry Du Quoin Pea
17 Perry Du Quoin Slack
18 sangamon Barclay Pea
19 Sangamon Dawson Pea
20 Sangamon Divernon - Lump
21 Sangamon Lowder Slack
22 Sangamon ... Ridgely Pea
V3 Sangamon Riverton Pea
24 Sangamon Sringfleld Pea
25 Sangamon Lump
26 Shelby Moweaqua Lump
27 Vermilion Catlin Screenings
2£ Vermilion Fairmount Screenings
29 Vermilion Muncie Slack
30 Vermilion Oakwood Lump
31 Vermilion Oakwood Pea
32 Vermilion Oakwood Screenings
33 Williamson Carterville Washed Pea
34 Williamson Herrin New Kentucky Pea
35 Williamson Herrin New Kentucky Screenings
BOILERS TESTED
The tests were made at the power plants of the University
and the neighboring towns, under water-tube and fire-tube boilers
of the following types:
Stirling water-tube boiler 2 settings
National water-tube boiler 2 settings
Heine water-tube boiler 1 setting
Babcock & Wilcox water-tube boiler 8 settings
Horizontal tubular boiler 11 settings
The settings of these boilers include the following:
1 Murphy smokeless furnace
2 Roney automatic stokers
2 Green chain grate stokers
PARRCANDBD™KS] FUEL TESTS WITH ILLINOIS COALS 29
1 Babcock & Wilcox chain grate
1 Brightman stoker
The remainder of the furnaces were hand-fired with plain or
rocking grates.
RESULTS OF TESTS
The results of these tests are shown in Tables III and IV, ar-
ranged according to the counties in which the coal was mined.
Table III gives the conditions of temperature, pressure, heating
surface and grate area under which the tests were made, and
Table IV gives a few of the most important results. In some
cases the heat value of the coals used was not obtained and sev-
eral of the columns dependent upon it are left vacant. The head-
ings of the tables are self-explanatory. Where a series of tests
was made with the same coals under like conditions, the average
of the series is reported together with the number of tests in the
series. Where the coal and steam have been assumed moisture
free and when the moisture in the coal was obtained by drying a
known amount above the boiler, indications have been made in the
tables .
In the computation of results, the usual correction for qual-
ity of steam by proportional weights of steam and water was used.
The combustible was computed from the weights of coal and ash
and not from the ultimate analysis of the coal, and it is, therefore,
in slight error to the extent of the ash which passed over the
bridge wall. The basis for the rating of the boilers varied from
10 to 15 square feet of heating surface per horse-power according
to the different types of boilers used. The B. T. U. of the coal,
given in the table, were obtained from an analysis of the sample
taken during the test.
•
DISCUSSION OF RESULTS
On account of the wide variation of conditions obtaining in
the tests reported, an exact comparison was hardly possible. A
general comparison of results with different types of boilers and
grates has, however, been attempted. Such a comparison is
shown in Table V, which contains the general average of the re-
sults of all trials made with the same type of boiler and grate,
irrespective of all other conditions. It also shows the average of
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gj s
36
ILLINOIS ENGINEERING EXPERIMENT STATION
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Equiv. Evaporation
From and at 212° Fah
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FUKL TESTS WITH ILLINOIS COALS
37
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38
ILLINOIS ENGINEERING EXPERIMENT STATION
the results of the ten highest tests together with the single high-
est result obtained. The basis of comparison is the equivalent
pounds of water evaporated from and at 212° F. per pound of dry
coal. The same table also contains the average of the results of
six tests with Illinois coals made by the Boiler Division of the
Fuel Testing Plant of the United States Geological Survey at St.
Louis. It is interesting to note that in these latter tests in which
hand -firing and plain grates were used, the results obtained are
better than any of the others recorded, including the results of
tests in which mechanical stokers were used. This fact may be
taken to indicate that the maximum efficiency of Illinois coals is
rarely obtained under present average conditions. It is probable
that with a closer study of furnace conditions, even these results
may be improved. The general tests reported in Tables 3 to 5 in-
clude a number of trials made with special objects in view. Several
of these trials are described as follows:
1. Tests of a small horizontal tubular boiler of 40 horse-
power, to determine its performance with varying rates of com-
bustion. The results of these tests are given below.
RESULTS OF A BOILER TRIAL SHOWING EFFECTS OF RATE
OF COMBUSTION ON THE PERFORMANCE OF
HORIZONTAL TUBULAR BOILER
Dry coal per square foot of
grate surface per hour
6.80
9.30
11.00
12.00
14.00
Equivalent evaporation
from and at 212° F. per
pound of dry coal
6.20
6.55
6.57
6.37
5.75
Horse-power in per cent of
rated capacity (40)
52 50
87.50
107.50
115.00
122.50
Temperature of escaping
gases
432.00
447.00
501.00
516.00
553.00
The same kind of coal was used in all these tests, and conditions
remained nearly constant. It is evident that the maximum results
were obtained with the boiler running at its rated capacity, with
the flue gas temperature about 500° F. With an increase in the
rate of combustion, the capacity and flue gas temperature increased
and the evaporation dropped off.
2. Tests to determine the effect of soot deposits on the evap-
oration of a small horizontal tubular boiler. These tests were made
on the same boiler as the preceding series and with results as
follows :
PABBCANDBDIBKS] FUEL TESTS WITH ILLINOIS COALS
RESULTS OF BOILER TRIALS MADE TO DETERMINE THE
EFFECT OF SOOT DEPOSITS ON THE EVAPORATION
OF A HORIZONTAL TUBULAR BOILER
• First Series
(5 days)
Soot allowed
to remain on
tubes
Second Series
(5 days)
Tubes cleaned
each morning
Third Series
(6 days)
Soot allowed to
remain on
tubes
Equivalent evaporation from and at
212° F. per pound of dry coal
6.20
7.04
6.23
Dry coal per sq. ft. of grate surface
per hour
13.40
9.09
13.40
Horse power in per cent of rated
capacity
111.00
99.00
115.00
Temperature of escaping gases
627.00
546 00
698.00
It is evident from the results that the effect of the soot de-
posit on the evaporation is not very marked. It is interesting to
note that in the first and last series, in which the soot was allowed to
remain on the tubes, the soot burned upon reaching a certain
thickness, leaving but a very thin layer. In all three series the
conditions were held as nearly constant as possible, although in
the second series the load fluctuated somewhat on the different
days.
40
ILLINOIS ENGINEERING EXPERIMENT STATION
8
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§I*J
^1
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BBECKKNBIDGE, 1
PAKB AND DIRKS J
FUEL TESTS WITH ILLINOIS COALS
41
3. Tests of a water- tube boiler with chain grate stoker to
determine the relative economy of a 6- inch and an 8- inch fuel bed
with various rates of combustion.
The results of these tests are best shown by the curves in
Fig. 9.
15 20 25 30 35 40
DRY COAL. PER SQ. PT. or- GRATEL SURFACE ptR Hrr-Lns.
FIG. 9 CURVES SHOWING THE RELATIVE ECONOMY OF A 6-iNCH AND
8-iNCH FUEL BED IN A CHAIN GRATE STOKER
They show that under the conditions of the test, the 8- inch
fire was the more efficient, giving an equivalent evaporation per
pound of dry coal 10 per cent greater than the 6-inch fire, when
operating at the rated capacity of the boiler. The same coal was
used throughout this series. The averages of the results of these
tests are reported in Tables III and IV, viz., Nos. 41, 42, 43 and
44. In Figs. 10, 11 and 12 are shown a few of the characteristic
results of boiler trials made on water-tube boilers with chain grate
stokers. These diagrams are plotted from the results of 38
trials, and each point on the diagram represents the average of 5
trials. It is safe to assume, therefore, that the results represent
average conditions.
42
ILLINOIS ENGINEERING EXPERIMENT STATION
IO5OO
11000
MEAT
11500
VAV.UE
12000 12500
OF DRY COAU-B.T. u.
FIG.
10 CHART SHOWING VARIATION IN BOILER PERFORMANCE WITH
COALS OF DIFFERENT HEAT VALUE
Fig. 10 shows the results of trials, in which coals of highest,
lowest and mean heat values were used, plotted on a basis of heat
value. The sudden drop in the equivalent evaporation per pound
of dry coal, with coals of low and medium heat value is no doubt
due to the large increase in the flue gas temperature with con-
stant rate of combustion and capacity. With coals of medium and
high heat value the equivalent evaporation increases with increas-
ing rate of combustion and capacity, the flue gas temperature
remaining constant. It is evident from the diagram that the effect
of the heat value of the coal is not very marked, a large increase,
however, -other conditions remaining constant, causing an increase
in the evaporation per pound of coal, as will be seen in Fig. 12.
BBECKENBIDGK, ~|
PABB AND DIBKSJ
FUEL TESTS WITH ILLINOIS COALS
43
IO »5 2O
DRV COAL PtR So FT
25 30
Or GRATt SuRrACt
35
PER HR. - LBS.
FIG. 11
CHART SHOWING VARIATION IN BOILER PERFORMANCE WITH
VARYING RATES OP COMBUSTION
In Fig. 11 the results of a boiler trial are plotted on a basis
of rate of combustion. It is evident from the diagram that the
equivalent evaporation per pound of dry coal increases with the
rate of combustion until the capacity reaches 100 per cent, or the
rated capacity, the heat value of the coal remaining approxi-
mately constant, the flue gas temperature at this point being 500°
F. With a further increase in the rate of combustion the capacity
and flue gas temperature still increase but the equivalent evapo-
ration per pound of coal decreases. This carve, if it may be called
such, might be named the characteristic curve of the boiler, and
is important because it shows the rate of combustion above which
the evaporation per pound of coal decreases.
ILLINOIS ENGINEERING EXPERIMENT STATION
20 40 60 00
HORSC-POWER . PERCENT
100 leo 140
RATED CAPACITY"
FIG. 12 CHART SHOWING VARIATION IN THE PERFORMANCE
OF A BOILER WORKING AT DIFFERENT CAPACITIES
The effect of capacity on the evaporation is shown by the
diagram in Fig. 12. It is seen that here as in the previous fig-
are the evaporation per pound of dry coal again increases with an
increase in the capacity due to an increased rate of combustion.
However, instead of attaining a maximum at 100 percent capacity,
it increases, with a further increase of capacity and rate of com-
bustion. At first sight this seems contradictory to the previous
diagram, Fig. 11; however, it is evident that this increase is not
due to this further increase in the rate of combustion and capacity,
but is due to the sudden increase in the heat value of the coal
(about 10 per cent) used.
V ARRANGEMENTS FOR FUTURE FUEL TESTS
In publishing this bulletin it has been the desire to record the
results of the most important tests of boilers fired with Illinois
FUEL TE8TS WITH ILLINOIS COALS 45
coals, that have been made up to date. During the year 1906 the
Engineering Experiment Station at the University purchased
and installed a plant designed especially for conducting a series
of fuel tests of Illinois coals. The plant consists of a 210 H. P.
Heine water- tube boiler together with a Green chain grate stoker
and a Sturtevant economizer and induced draft fan and engine.
This boiler is a duplicate of the boilers used by the United States
government in the fuel tests in progress at St. Louis under the
direction of the United States Geological Survey. It was thought
that in this way the fuel tests here at the University would be in
a measure comparable with the tests made by the government on
coals from all parts of the United States.
The rapid growth of the industrial interests of Illinois de-
mands a careful study of the great fuel supply, and no 'effort
should be spared in the introduction and promulgation of improved
methods and processes in the production, treatment and con-
sumption of its coal. In the tests of Illinois coals which it is now
proposed to make, less attention will be paid to routine boiler
tests, familiarly known as such, and more attention will be given
to a scientific study of fuel treatment before burning and to a
study of those furnace constructions and conditions which give
promise of maximum results. In order that future tests may be con-
ducted along lines which will meet with the general approval of
the various interests of the state, a Conference Committee on
Fuel Tests has been appointed consisting of the members named
below and representing the organizations indicated:
H. Foster Bain, Director State Geological Survey, Urbana,
111., representing the State Geological Survey;
A. Bement, Consulting Engineer, Chicago, the Western
Society of Engineers;
Edwin H. Cheney, President Fuel Engineering Co. , Chicago,
the Building Managers' Association of Chicago;
F. H. Clark, Gen. Supt. Motive Power Burlington Road,
C. B. & Q. Ry., Chicago, the Western Railway Club;
Adolph Mueller, President H. Mueller Mfg. Co. , Decatur,
111., the Illinois Manufacturers' Association;
Carl Scholz, President Coal Valley Mining Co., Chicago,
the Illinois Coal Operators' Association;
A. V. Schroeder, Decatur Railway and Light Company,
Decatur, 111. , the State Electric Light Association;
46
ILLINOIS ENGINEERING EXPERIMENT STATION
Wm. L. Abbot, Chief Operating Engineer, Chicago Edison
Co., Chicago, the Board of Trustees University of Illinois;
FUEL TESTS WITH ILLINOIS COALS 47
L. P. Breckenridge, Director Engineering Experiment
Station, University of Illinois, Urbana, 111.
Reference has been made to the government fuel tests at
St. Louis. It should be stated that the work of the boiler division
of these tests has been carried on under the direction of the
Director of the Illinois Engineering Experiment Station, who
will also have charge of the tests made at the University of Illinois.
Copies of Professional Paper No. 48, containing a report on the
operations of the government coal testing plant at St. Louis may
be obtained upon application to a member of Congress or to the
Director of the United States Geological Survey, Washington, D.C.
It is not the intention of this bulletin to discuss the subject of
fuel testing. A future bulletin will take up that subject and will
also describe in full the plant provided for such tests at this
University. Attention is called, however, to the facilities now of-
fered for this important work. It is hoped that mine owners and
manufacturers will find it advantageous to cooperate with the En-
gineering Experiment Station in the proposed tests. The Station
Staff will always be glad to receive such suggestions concerning
this work as those interested may desire to offer.
VI CHEMICAL ANALYSIS AND HEAT VALUES OF
ILLINOIS COALS
By S. W. PARR, Professor of Applied Chemistry
The accompanying results of chemical analyses of Illinois coals
may be divided into three classes: first, those which were directly
connected with the boiler tests conducted by the department of
Mechanical Engineering, and which are listed in a separate table,
covering such work from the year 189 1 to 1905; second, in connec-
tion with thesis work by Mr. F. C. Koch in 1901, there were
assembled by him the results of all analyses of Illinois coals which
had been made by the department of Chemistry previous to that
date. These results were published together with his own work
in a bulletin through the courtesy of Secretary Ross of the Bureau
of Labor Statistics in the report of that Bureau in 1902. They
are designated in the tables by the letters B. L. S. The third
series of results comprises the work on one hundred fifty
samples of Illinois coal collected in 1904 and published in a
separate bulletin in connection with the exhibit of mines and min-
48 ILLINOIS ENGINEERING EXPERIMENT STATION
erals at the St. Louis Exposition. These results are designated
in the tables by S. W. P. The sum total of data which has thus
resulted, while of a somewhat desultory nature, constitutes a very
considerable contribution to our knowledge of the constituents of
Illinois coals. It is to be noted that the processes employed in
connection with this series were confined almost exclusively to the
method of proximate analysis. In the future the more exacting
demands of modern methods will require extended data such as
are furnished by both proximate and ultimate analysis, including
of course the determination of calorific units. It may be well there-
fore, at the present time, to assemble the information obtainable
up to the present date, compiling it as in the accompanying tables,
and also to discuss briefly some of the terms which are used in
connection with the chemical work on coals. The chemist employs
terms and processes which are also used by the engineer, but it
does not always follow that their use of terms is in accord.
Moisture. — Moisture in coal is constantly undergoing a change
as to quantity. The percentage contained at the time of break-
ing out the coal from the vein is greater than at any subsequent
stage of its history, unless possibly it be under the conditions of
rain or snow or drenching with the hose. Some of this moisture
which is normally contained in the coal is lost when the coal is
exposed to the air, being in this respect like water which has been
poured upon the coal. But there remains moisture in the coal
after air- dry ing and which is removed only at the temperature of
boiling water. This moisture is described as hygroscopic. If now
the chemist works upon a sample which is overcharged with mois-
ture, as is the condition when the sample is freshly mined, it will
be constantly losing in weight and modifying his results. Simi-
larly, if he works upon a sample which has been completely dried
in the oven, it will have great avidity for moisture and be con-
stantly gaining in weight throughout his work. He, therefore, pro-
ceeds in his determinations, as a rule, with the coal in that condi-
tion which is least affected by external conditions, viz., in the air-
dry state with the normal amount of hygroscopic moisture pre-
sent, but without the excess of water, which might be termed
water of saturation.
Therefore, we have three distinctly different conditions: first,
the wet coal; second, the air-dry coal; and third, the oven-dry
state. The engineer, however, not having to do with the condi-
TE8T8 WITH ILLINOIS COALS 49
tions under which the chemist works, recognizes only the two
phases, either the wet or dry, and by this latter term he means
the oven-dry state. The failure on the part of the engineer and the
chemist to recognize these terms often leads to misinterpretation
of results. The chemists, therefore, should agree to such use of
terms relating to water as have become firmly established in en-
gineering literature: viz., that dry coal refers to moisture free
coal or to the oven- dry state, and second, that wet coal refers to
the condition as received or previous to any process of air-drying,
and that it is one or the other of these conditions that is of inter-
est to the engineer, regardless of how important it may be to the
chemist to proceed upon the basis of the air-dry condition.
It may not be out of place further to indicate how results may
be transferred from one basis to the other. It is not an uncom-
mon practice for the chemist to report his results on the air- dry
basis, in which case he should also report the amount of moisture
lost upon air drying, provided his sample comes to him sealed in
such a way as to make this factor possible. Suppose, for exam-
ple, that the loss of moisture upon air-drying is 4 per cent, then
all his results reported on fche air-dry basis would be changed
to the wet coal basis by multiplying each by 96 per cent; not by
dividing by 104 per cent as is often erroneously done. This will
make small difference in a constituent which has a low percentage
factor, but the error is very considerable in a factor like the fixed
carbon which is from 40 to 50 per cent. This may seem like a sim-
ple arithmetical problem to mention in this connection, but it is
one not always correctly interpreted.
Conversely, if it is desired to change factors to the dry coal
basis, each factor should be divided by 100 minus the percentage
content of water in that condition from which the transfer is be-
ing made. For example, if we are calculating this coal from the
air -dry state, supposing it to have 6 per cent of moisture present,
each factor should be divided by 94 per cent, but it should be noted
that if we are calculating from the wet-coal condition our divi-
sor will not be 100 per cent minus the sum of the two factors, 6 and
4, as in the above illustration, but 100 minus 96 per cent of 6
plus 4, or 90.24. Here again is a not uncommon place for stum-
bling in what might seem to 'be a simple arithmetical problem.
Volatile Matter. — When coal is subjected to high temperature
out of contact with the air, a considerable amount is driven off as
50 ILLINOIS ENGINEERING EXPERIMENT STATION
volatile matter. This includes, also, of course, any moisture in
the sample, if we start with a portion which has not been dried in
the oven. Now an even greater discrepancy in the use of terms
has come into use in connection with this constituent than is the
case with different forms of water. One of the oldest terms is
that of volatile carbon. This is both incorrect and meaningless
because carbon is not volatile, and because the constituents of this
material are numerous and complex. The term that is perhaps most
frequently met designates this material as volatile combustible.
This again is incorrect and misleading, as this material in the or-
dinary bituminous type of coal has from one-third to one-half of its
weight made up of non-combustible material. It is evident, there-
fore, that the only proper term among those commonly in use for
this constituent is that of volatile matter. The only restriction in-
deed in connection with this term is to understand, as is the uni-
form custom, that the moisture of the coal is not included. A word
may be in place here in connection with a term which is occasion-
ally met, and is likely to be more frequently used than formerly.
This term is intended to designate that part of the volatile matter
which does not burn. This constituent is sometimes referred to
as "water of composition". It is not included in any of the re-
suits listed in the following tables, and hence its use does not en-
ter into any of the discussions in this bulletin. It is noted in this
connection, however, in order that it may not be confused with
any of those terms which are intended to designate the water in
its ordinary form and which are capable of being driven off at
the temperature of boiling water. This property does not belong
to the water of composition, as this substance like the other part
of the volatile matter, requires a red heat for its dissociation.
Fixed Carbon and Ash. — Concerning these constituents there
is no disagreement as to the use of terms unless it be the occasion-
al use of the word coke. Coke in its proper and technical sense
should apply to the residue including the ash after subjecting the
coal to destructive distillation. It is, therefore, not proper to
designate the fixed carbon as coke, though it would be proper, of
course, to use the term "coking carbon" in this connection. The
preferable term and the one commonly employed, however, for
this material is that of fixed carbon.
Methods of Analysis. — The methods of analysis employed are
those in common use and their description is so easily accessible
BBECKENBIDGE. 1 FTTlrr TT^qT^^ftl^tf V£xs*#nTQ PO A T Q ^ 1
PARR AND DIRKS J U -^ L ^8 J »fc*SLl±-ai»4rnN U S L/UAL.S
that no repetition is necessary here. Reference may be made to
the report of the committee of the American Chemical Society on
coal analysis.1
Calorific Value. — The determination of heat units in coals is,
of course, a necessity in connection with any well conducted boiler
test. Two systems of units are employed, viz. , the kilo calories
and the British Thermal Units, designated as B. T. U. Each unit
is the measure of heat imparted to the water by an equal weight
of coal. They would, therefore, be identical if it were not for the
fact that the one is read on the Centigrade scale and the other on
the Fahrenheit scale. The transfer, therefore, of calories per
kilo over to B. T. U. per pound is effected by multiplying by the
ratio of 9:5 or 1.8.
There are four types of instruments in use for measuring the
heat value of coals. The first and most elaborate is the Mahler
instrument which has numerous modifications as to detail, but
which embodies the use of a steel bomb capable of maintaining
oxygen from twenty to twenty- five atmospheres pressure. The
next in the order of time is the Fisher calorimeter which burns
the sample of coal in a small chamber supplied with oxygen at at-
mospheric pressure. The third type may be designated as the L.
Thompson calorimeter, wherein the coal is mixed with a chemical
which in itself supplies the oxygen for carrying on the combus-
tion and in which the gaseous products are allowed to bubble up
through the water, thus imparting their heat to the liquid. The
fourth type may be designated as the Parr calorimeter which also
employs a chemical having its own supply of oxygen, but which
absorbs the gaseous products, thus retaining all the heat of the
reaction for more accurate measurements by the thermometer. Of
the second and third types, it may be said that owing either to in-
completeness of combustion or to loss of heat by transmission of
the gases, results are obtained which are not of sufficient accuracy
for reliable work. Results from the Thompson calorimeter are
reported by certain authorities to admit of variations amounting
to 15 per cent. The Mahler type of calorimeter is accurate when
operated by one thoroughly familiar with such processes. The
Parr calorimeter is the one used in connection with the analyses
in these tables of all coals made since 1900, and is now the instru-
IJour. Am. Chem. Soc. Vol. XXI. p. 1130.
52
ILLINOIS ENGINEERING EXPERIMENT STATION
ment most commonly used in technical work. A brief description
of this apparatus follows :
Pig. 13 shows the relative position of parts. The can A. A.
for the water has a capacity of 2 litres. The insulating ves-
sels B.B. and C.C. are of indurated fiber. The charge of coal and
chemical is put in the cartridge D. Upon ignition, the heat gen-
erated is imparted to the water and the rise in temperature is in-
dicated on the finely graduated thermometer T. The cartridge
or bomb rests on the pivot F and is made to revolve, and by aid
of the small turbine wings attached effects a complete circula-
tion of the water and equalization of temperature.
The reaction accompanying the combustion may be repre-
sented by the equation:
56Na2O2 -j- C25H18O3 = 25 Na2CO3 -f- 18 NaOH -f 22 Na2O
Sod. perox. Coal Sod. carb. Sod. hydrate Sod. oxide
FIG. 13
FUEL TESTS WITH ILLINOIS COALS 53
With certain substances such as coke, anthracites, petrole-
ums, etc., a more strongly or vigorously oxidizing medium is
needed than exists in the peroxide alone. This may be secured
by various additions. The most effective are: A mixture of po-
tassium chlorate and nitrate in the proportion of 1 to 4 and this
mixture used in the ratio of 1 to 10 of the sodium peroxide; an-
other effective mixture is an addition of potassium persulphate in
the ratio of 1 to 10 of the sodium peroxide. Other substances fa-
cilitate the oxidation, notably ammonium salts and certain organic
substances, as tartaric or oxalic acid, benzoic acid, etc. In the
work on Illinois coals, while ordinarily no extra chemical would
be necessary, still in certain cases, such as extra slaty coals and
coals with excessive volatile matter, and also to guard against
variations in the quality of the sodium peroxide, a mixture as first
described above, of chlorate and nitrate, has uniformly been
used throughout these tests.
Further extension of the use of the instrument to other types
of coal and to petroleum has made it necessary to extend still fur-
ther the oxidizing power of the chemicals employed beyond what
is afforded by the chlorate mixture. In addition to this the use
of the residue for determining the total carbon and sulphur has
made it highly desirable in such additional chemicals to avoid the
use of compounds containing carbon or sulphur. To meet these
conditions, the so-called "boro- mixture" has been devised. It
consists of:
Boric acid 11 parts
Potassium chlorate 4 parts
Magnesium powder 1 part
Its correction factor is found by trial with a pure chemical of
known heat value, such as napthalene or by burning with a coal
whose heat value is already accurately known. This mixture has
the further advantage of carrying on a combination with material
so low in carbonaceous matter as to be non burning by ordinary
methods, such as ashes and coals of very high ash content.
Still further modifications relate to the bomb as shown in
Fig. 14, and have to do mainly with the avoidance of screw
threads on the interior of the combustion chamber, especially in
the upper part, where particles tend to lodge and thus escape
combustion; also in jacketing the lower part of the chamber to
avoid direct contact with the water, thereby avoiding rapid
54
ILLINOIS ENGINEERING EXPERIMENT STATION
cooling of the parts and extending somewhat the period of high
temperature, thus securing a more perfect combustion.
a
FIG. 14
Calorific Values By Calculation. — Numerous methods for calcu-
lating the calorific value of coal have been proposed, but no
method can be said to have any value which is not based on a
knowledge of the percentage constituents of the total carbon,
available hydrogen and sulphur. Even under these conditions
the results by calculation are not always in agreement with the in-
dicated results by means of the calorimeter, and in any event, of
course, results from proximate analysis do not furnish the neces-
FUEL TEST8 WITH ILLINOIS COALS 55
sary data for this calculation. When this method is used the Du-
long formula is considered the most nearly accurate and is as
follows:
Gal. = 8080 + 34,500 H + 2250 S
In the results here recorded the necessary factors were not
always available for applying this formula, but it is the one used
wherever calorific values by calculation are included.
56
ILLINOIS ENGINEERING EXPERIMENT STATION
BBECKENBIDGE. ~|
PAKB AND DIRKS J
FUEL TESTS WITH ILLINOIS COALS
57
i— o «— cc « w eo
— owi- • -irtt-osco -OTf — <oeoooooo
0 oo « eo c» eo cc w os co
r- o • «o oo «D o >c co w s kr
'--— • eeccc
IIIIIII i
»H 8- tj ^ S_ ti !H .
O) 0> <D <U 01 <D <D •
ooooooooooooo
SSSS
CCCCQflCfi
oooooooo
= = = =
58
ILLINOIS ENGINEERING EXPERIMENT STATION
S|-a
^8
*°%
«£Q
— — ^ • C-l -H
Volatile
Matter
xed
rbon
Analys
Obtain
from
of
sis
1 Q PL k cc t/5 -Ji (n c/5 j/i PH dl c/i en c/5 Q til CU (^ CL^ PL! ol C^ di
£S
: :
S * 0>
plRRCANDRmR!s] FUEL TESTS WITH ILLINOIS COALS
59
^eoosco'wcoeo ~-~ :Mweo«^a>f •••••• '« ' «o « «^o cj co -HCO -£eo eo : :oo-^(N :*ieococo
^SS^ScS!
58^SS2^?
:g>owgtf»2<
gS2S8So888SS2SS8S58 SScoSS?
_ jj j J^-^iJ J J j J JJ JJ JJJ^^^
X5 QO 00 C
35 I- O5 J
^5f2?!s ! • -a^ !.:::: ^>>>>> |
a : • & : : •' : : : :| :'
S*'rt* " W * * * ™ " G f ~ ' '
• •q- -S B- • -f-c _••
•H^^:^-^ fe 3 : -o':' -'Co
c/} : • c/3 '• •^^"^>"'^^'a)-2cfi£^aoa • ^ Q. • Q. • ® "S
B§^35gl|l|-C :-s :-=^^-2 ^ :a"^"^l>.SSSSsl3a'isl j :^^bt«
MMiJiiliU
60
ILLINOIS ENGINEERING EXPERIMENT STATION
S.2-
BgJ
H'O^
-cxsQ
Volatile Mn
Matter 1V
Fi
Ca
Analysis
Obtained
from
of
sis
COOOOGS • • • oo cO •^^wrocccocc^fi
CO <N ' ' •* CO <
i^oocooo • • » IN -f « — i
t-oc»O5O5i^»nt-os«3cocooo
^cfic/3^CupME^(-!!iipLj(iic/i7}x(-5IXDHP4P-c/2c/)c/ic/i
rr -r Q r
:S^
s :
. . . ea .
p. : :^ o
.g : :.aa
CJ S : : « fl
c c c c a a c
FUEL TESTS WITH ILLINOIS COALS
61
ao i OD oo t 0 —
» > 0 a
« o» »o « <o a «e t ie »o b » o c> o o o o
^w^wwwwwwwwww~'w^wwiwJ^wp^;F^;p-3;^cg -^
62
ILLINOIS ENGINEERING EXPERIMENT STATION
I — C* OO CO O* <N — CO — <N CO JO CO (M <N • N 9* • •*»»-««
10 Oi <o ao — co -coco •<* . c> 3. _ .000 • -o»neo
t-5i~— «•»*—' -oooo — -floor- -ao— • . -^ ^ ^
ffi^eowfrieo • "^ • • • • • '-M '-^n ' '-~<n '• :«eoco
"
FUEL TESTS WITH ILLINOIS COALS
63
— 9t — « (MM CO O ft — (M CO CO •* CO CO O CO — CC ^H <N — < I
^
'^fi
^.^^ j'^'|^^^^ j j^ § j ^ j j j>* § § j j^^^ g § §
co^tfSMcnco'(«tfSapQocPcpc«(«cdpdcd6«
64 ILLINOIS ENGINEERING EXPEEIMENT STATION
• • • »ft t~ ^* co t>- -os --^aco^ • • coo *n *»•* — oo . o CD »~eo t-
• • -ookftoooo • «o -co^Ofc • • co ^ c* >ft co c» co • wxocoM
• • •^T-.^wti -co • — co oo co • • co t- in iO — ,-1 •* • — ^-iftirt-^-i
co -cocofo
coco-«wcoe(? • • • cocoffeoMeo • -COIN -coeocccoco"
HI
IP
ft ft ft ft
eaaa
: :§§§ : :
' Gft
.2 a a
3 ftftcS O c3
y
c c c :tf
S £ £ £ fl G c c -~ •- -H ^ :r- r ^ -r :rr r - ; S S S <u a> ® > > > > > > 5 £ 5
rrrS:r.rH.".s.J->->->->>->->->>>->gggaft&!^^^^:^!^^r^fa.
oo 1 1 11111 i§«iii5§is gll'SECS'l^S'g'Sia ^^
ccpsp .s^ss^^^^^^^22222222222°2222222
". I S | SSS55 1 f § 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
r
pABB°ANDBDmKS] FUEL TESTS WITH ILLINOIS COALS 65
c§ e§ 08 £J w" 55 co' eS
QOCfll
ggjSi
§ : §|| :' : : iSS^SSSg.SSS :
i-a • cflcflcfl •
> t- t- r- • ; ; t- t- t- t-
! ffi • • O * • ; ;
p, . . • . . o ^ d "5 * . ; • ; • "3, • •
'. '• [a-4«'*«««<z<s3^^1i< |^' | g : : i
^— jdj
I'SjDjOkS
: "> "> "> '> "> "> '> '> '
csSSSSS- -
bus e83SS *
3 =- f- o O O 3
CQ[lJ^^'W^Ww"~'W^W~"w
" d d c3 d d d d d d d d o o a o c c o s c c
!WllllllsIilI|
13
66
ILLINOIS ENGINEERING EXPERIMENT STATION
TABLE VIII
LIST OF ILLINOIS COALS ANALYZED. ARRANGED BY TOWNS
Town
County
Ref . Number
in Table of
Analyses
Assumption .
Christian
8-12
Astoria
Fulton
28-30
Athens
Menard .
185-188
Auburn
Sangamon
359-255
Barclay ....
Sangamon.
256-258
Benton
Franklin
27
Bloomington ....
McLean
110-116
Braceville
Grundy
50-51
Braidwood
Will.
327-328
Breese
Clinton
20-21
Briar Bluff
Henry
57
Brighton
Macoupin
124
Bush
Williamson
332
Buxton . . .
Clinton
22
Cable
Mercer
196-197
Canton. . .... . .
Fulton
31-32
Cantrall
Sangamon
259 260
Carbondale
Jackson
62-65
Cardiff
Livingston
95-96
Carterville
Williamson
334-345
Catlin
Vermilion
296-299
Centralia
Marion
145-148
Colchester.
McDonough
109
Coif ax
McLean
117
Collinsville
Madison.
138-139
Cuba
Fulton
33-36
Danville.
Vermilion. .. .
300-310
Dawson
Sangamon
261-264
Decatur . .
Macon
118
Delafleld
Hamilton .
54
De Soto
Jackson
66-71
Divernon
Sangamon
265
Donkville
Madison
140-141
Dunfermline .
Fulton
38
Du Quoin
Perry
210-223
EdwardsviUe. . .
Madison,
142-143
Eldorado
Saline
239-243
Elm Grove
Ad ams ...
1-2
Elmwood
Peoria
203-207
Etherly ...
Knox
76-77
Fairbury
Livingston
97-98
Fairmount
Vermilion
311-313
Farmington.
Fulton
39-42
Fiatt
Pulton
43
Flatrock
Crawford .
26 '
Forest-
Livingston
99-100
French Village
St. Glair
233-234
Galatia
Saline.
244
Galva
Henry
58
Gilchrist
Mercer . . ....
198
Glen Carbon
Madison
144
Grape Creek
Vermilion
314-316
Greenview
Menavd
189-191
Greenridge
Macoupin
125-126
Harrisburg .
Saline
245-251
Herrin
Williamson
346-352
Holies
Peoria
208-209
Ivesdale
Champaign
7
Joliet
Will
329-331
49
Kangley
La Salle
79-80
Kewanee
Henry
59-61
Kinmundy
Marion ...
149-150
Ladd
Bureau
3-4
Lake Creek . . .
Williamson. . .
353
BRECKENBIDGE, ~]
PABB AND DIBKS J
FUEL TESTS WITH ILLINOIS COALS
67
TABLE VIII (Concluded)
Town
County
Ref . Number
in Table of
Analyses
La Salle
La Salle
81-84
Lauder
Williamson ...
354
Lincoln. .
Logan
101-106
Litchfleld
Montgomery.
201-202
Bureau
5
Lowder
Sangamon . ...
266
McLeansboro
Hamilton
55
Marissa
St. Clair
235-238
Middletown
Menard .
192-193
Moweaqua
Shelby
289-295
Mt Carbon
Jackson.
72
Mt Olive
Macoupin .
127-132
Mt Pulasld
Logan.
107-108
Perry
"24
Murphysboro
Jackson.
73-75
Niantic . . . .
Macon
119-123
Norris
Fulton
44-45
Oakwood
Vermilion
317-322
Odin
Marion .
151-178
Oglesby
La Salle
85-88
Palmyra
Macoupin. . .
133-135
Pana
Christian
13-19
Paradise
Coles ....
25
Peru
La Salle
89-90
Petersburg
Menard. .
194-195
Perry
225-226
Rido-ely
Sangamon
267-268
Sangamon
269-274
St David., .
Fulton
46-48
St John
Perry
227-228
Sandoval . . ...
Marion
179-181
Sherrard
Mercer
199-200
Soperville . ...
Knox
78
Sparta
Randolph
229-230
Sangamon
275
Springfield
Sangamon.
276-283
Sangamon
284
Spring Valley
Bureau
6
La Salle
91-94
Sugar C**eek
Wabash
326
Williamson
355
Tilden
Randolph
231-232
Toluca
Marshall
182
Trenton .... ....
Clinton
23-24
Virden
Macoupin.
136-137
Marshall
183-184
Westville
Vermilion
323
S Westville
Vermilion
324-325
S Wilmington
Grundy
52-53
68 ILLINOIS ENGINEERING EXPERIMENT STATION
PUBLICATIONS OF THE ENGINEERING EXPERIMENT STATION
Bulletin No. 1. Tests of Reinforced Concrete Beams, by A. N.
Talbot. 1904.
Circular No. 1. High-Speed Tool Steels, by L. P. Brecken-
ridge. 1905.
Bulletin No. 2. Tests of High- Speed Tool Steels on Cast Iron,
by L. P. Breckenridge and Henry B. Dirks. 1905.
Circular No. 2. Drainage of Earth Roads, by Ira O. Baker.
1906.
Bulletin No. 3. The Engineering Experiment Station of the
University of Illinois, by L. P. Breckenridge. 1906.
Bulletin No. 4. Tests of Reinforced Concrete Beams, Series
of 1905, by A. N. Talbot. 1906.
Bulletin No. 5. Resistance of Tubes to Collapse, by A. P.
Carman. 1906.
Bulletin No. 6. Holding Power of Railroad Spikes, by R. I.
Webber. 1906.
Bulletin No. 7. Fuel Tests with Illinois Coals, by L. P. Breck-
enridge. 1906.
UNIVERSITY OF
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AMICS, and the GRADUATE SCHOOL.
A Summer School n
A Military Regiment is
Feel i am i ; oung
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ural Hi> Minois
Rivf
Engineering Experiment Station riized
. • ^ring
•
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phlets.
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