January, 1932
I N D U S T R I A L A :ND E N G I N E E R I N G C H E M I S T R Y
A typical elevator installation is shown in Figure 12; the 10 X 6 inch monel-metal buckets on a belt elevator are used for handling salt at’ a western salt plant. Promal chain, which is especially suitable for conveyor use, was developed by the Link-Belt Company of Indianapolis and for the past four gears has proved a very superior tnetal for chains. Promal is a specially processed malleable iron, the process employed transforming it into a material of radically different microstructure and physical properties. This metal has many excellent characteristics which make it extremely satisfactory for use where cast chains are used on conveyors, or elevators where abrasive materials are contacted. Cement mills, fertilizer plants, chemical plants, sand and gravel plants, and coal mines, as well as pulp and paper mills, have been the proving ground for chains made of Promal. Everyone of them has obtained from one and a half to five times the wear from Promal chains that they have from chains made from the best available iron. Some of the physical properties of this metal are:
Yield point lbs./sq. in. Ulti,mate stkenpth, lbs./sq, in. Fatigue strength Ibs /as. in. Elongation, % id 2 inches Modulus of elasticity Coefficient of thermal expansion, inch Specific gravity .4verage Brinell hardness
33 50 000
70:OOO 33,000 10 to 14
26,000.000
0.0000109
7.35
170 to 190
COSCLCSION f h i l e only touching upon the wide field of application and citing few specific examples of installations in the chemical industry, some idea is given of the extent to which mechanical handling enters into the expediting of deliveries, enlarging handling capacities, and reducing production costs. Good engineering must extend to every detail of a conveying system, and must especially consider the nature and size of the material to be handled, whether it is sticky or abrasive, and the manner in which the material is to be fed to and discharged from the system. RECEIVED August 11, 1931
Power and Fuel Gas from Distillery Wastes C. S.BORUFF AND A. M. BUSWELL, State Water Surrey, Urbana, Ill.
D
HOT DISTILLERY wastes containing 3 to the same ( W h ’ and quantity ISTILLERY w a s t e s in 4 per cent solids and 0.2 per cent organicacids of gas as the organic matter from the main always have sewage. been a liability* Methm a y be fermented thermophilically to produce The settling of beer-slop Tvaste ods of s a l v a g i n g t h e m for uge as stock food or fertilizer fuel gas (a mixture O f mdhane and carbon diwith sewage, however, removes oxide) at very low cost. From an average daily only about 30 per cent of the base have been i n v e s t i g a t e d volume of 1,j00,000 gallons of this waste, 3,600,total waste load, leavingtherest a n d some a r e used by dis000 cubic jeet f, gas could be produced. A to be handledbyactivatedsludge tilleries today. Methods of recovering the organic acids and or t r i c k l i n g filter units. The gasijcation of 58 to 72 per cent of the organic. supernatant liquor from a setglycerol have also been studied. The use of this m a t e r i a l as a matter is accomplished in 2 to 6 days. tling tank being treated with 1 binder for fuels and f o r o t h e r A stable inoffensive sludge (residue) is formed, volume of beer-slop to every 9 as well as (1 liquor that can safely be drawn to volumesofaveragesewagewould p u r p o s e s (9) has also been proposed. Kone of these prosewers. still be 2 to 3 times as strong cedures, however, has netted a a s a v e r a g e s e t t l e d sewage. This would place an excessive substantial profit. The sanitary disposal of beer-slop wastes is a serious load on the activated sludge or trickling filter units. “The problem. Usually they are about 20 times as heavy as cost of treating such a strong waste,” Hatfield says, “makes normal sewage and contain a very high percentage of organic its recovery as a by-product within the industry necessary matter. The literature indicates that treatment plants and advisable.” At the time of Hatfield’s studies the Comhandling sewage which contains a moderate amount of this mercial Solvent Corporation was fermenting corn mash. The residue from this fermentation (1,250,000 gallons a day) waste will operate with difficulty ( 6 ) . Danok (5) suggested a pure culture method of decompos- had a total solids content of 11,196 p. p. m. Hatfield calcuing such wastes. He states that the success of his method lated the population equivalent of these wastes to be about depends on the use of a sterile waste and a pure culture of 800,000. Since that time the Commercial Solvents Corporaspecific bacteria. A British patent ( 1 ) outlines a process tion has used rye and the solids content of its waste has for the aerobic or anaerobic decomposition of such wastes been materially increased. by the addition of “betaine-destroying organisms.” h’eave Gas YIELDSFROM FERMENTED WASTES and Buswell ( 7 ) , in 1928, reported studies on the anaerobic stabilization of slops from an alcohol plant. I n their batch On the basis of related studies ( 2 ) by the writers, it was experiments they found that slop diluted 1 to 4 still inhibited thought advisable to see what gas yields could be obtained bacterial growth, but that when it was diluted 1 to 9 with by the fermentation of the undiluted Commercial Solvent sewage and inoculated with sewage sludge itr fermented waste. As the temperature of the raw waste ran from smoothly a t 77-81” F. (25-27” C.), with the formation 194” t o 203’ F. (90’ to 95’ C,),it was decided to t r y a thermoof carbon dioxide and methane, but with the destruction philic digestion. Such fermentations have long been recognized as much more rapid than those conducted a t ordiof only 55 to 65 per cent of the solids in 73 days. Hatfield (4), after studying the rate of settling and gasifi- nary mesophilic temperatures. Table I gives an analysis cation of Commercial Solvent beer-slop waste, reported of the waste used in this investigation. About half the that when diluted with 6 to 13 parts of sewage the solids solids were found to be filterable. This waste is much were easily settled out. He found that the sludge was heavier than that used in the mesophilic studies by Neave readily digested with sewage solids and that it produced and Buswell ( 7 ) and by Hatfield (4).
INDUSTRIAL AND E N G I N E E R I N G CHEMISTRY
34
Anaerobic fermentation tanks (1 to 2 gallon capacity) were constructed with tubes for feeding and withdraning liquor, residue, and gas. The gas was collected in gasometers and analyzed frequently. These fermentation tanks were started by adding liquor and sludge from a therniophilic tank in which an active culture of gasifiers had heen developed. All tanks were operated a t 127" F. (53" C.). The fermentation tanks, after they were well started, were fed a t different rates. For example, one tank was fed a t the rate of one-half its volume of waste per day (tank volume = twice the volume of waste), and another a t the rate of one-third its volume of waste per day (tank volume = 3 times volume of waste). These experiments extended over seven months. The first three months were devot'ed to a determination of the rate a t which the sour slop liquor could be fed to the fermentation vessels without inhibiting the bacterial action. The data submitted were obtained from a subsequent uninterrupted 4-month. run. T.4BLE I.
AkN.41.YSIS 07
C O M W E X Z I 11, 4 STE
. .
Figure I and Table I1 summarize the gas data. By feeding slops a t the rate of 1 volume a day to a tank of twice this volume, 14 volumes of gas per volume of slop, in other words, 7 volumes of gas per unit of tank volume, can be obtained daily. If, on the other hand, the tank has a 4volume capacity, giving the waste a longer detention period, 16.8 volumes of gas may be recovered each day from 1 volume of waste fed. If the same volume of waste is fed each day to a tank 6 times this volume, giving the waste a detention period of 6 days, 18 volumes of gas, or 3 times the fermentation tank volume per day, can be recovered. The gas recoveries for the different tank volume to waste volume ratios are given in Table 11. TABLE11. GASPRODUCTIOU D ~ T AND A R E L 4 T E D CALCULkTIOAS
3
4 6
5.2 4.2 3.0
TNTEREST,~
IYORTIZATION AND
. 4 N 4 ~ i ' S I b OF
CHI
Cot
%
%
55
43
..
58 58
..
40 40
REPAIR CHARGES PER Gtsa 1000 C L B t u I T Gxs
550
..,
580 580
Cents 2.34 3.15
3.90 5.46
KO. 1
of gas per tank volume per day (Table 111). This has been considered a very rapid digestion. The writers have been able to feed 930 pounds of volatile matter per day per 1000 cubic feet of tank capacity and to recover 7 volumes of gas per unit of tank volume per day. With the lower rate of
SOLVEUT BEER-SLOP
pH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 . 5 - 5 . 3 Total solids, p. p. m.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28,000-40,000 . . . . . . . . . . . . 26,000-36,000 Volatile matter, p. p. m.. . . . . . . Volatile acids (as acetic), p. p. m. ............ 1,800-2,400 14-86 Ammonia nitrogen, p. p. m . . . . . . . . . . . . . . . . . . . . . . . . . . . . Total nitrogen, p. p. m.. . . . . . . . . . . . . . . . . . 1,400-1,900 .... B. 0. D., 5-day, p. p. m.. . .............. 17,000 Oxygen consumed, p. p. m.. . . . . . . . . . . . . . . . . . . . . . . . . . . . 10,000-20,000 194-203 Temperature of waste as drawn, O F.. . . . . . . . . . . . . . . . . . . Total solids: Ash, % . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Protein (org. N X 6.25), %. . . . . . . . . . . . . . . . . . . . . . . 32 Fats and oils, Yo., ................................ 8 21 Total carbohydrates (less cellulose) as glucose, 70. , , , Undetermined (crude fiber, etc.), % . . . . . . . . . . . . . . . . . . 29
YIELD OF GAS (Volumes per Tank Volume T A N K per VOLUMEDay) Tzmes volume of waste 2 7 0
Vol. 2 i .
CHARACTER OF RESIDUAL WASTE
Sludge fairly stable, overflou liquoi unstahlec Liquor unstabled Liquor unstable6 Liquor fairly stable, but contains only 10 per cent of original solids$ sludge stable cent Nn.
Heukelekian and Rudolfs (6) reported that they can feed thermophilic sewage digestion tanks a t a rate as high as 77 pounds of volatile matter per day per 1000 cubic feet of tank capacity (23.5 grams per day per 19-liter tank). From this digestion they were able to recover 1.2 volumes
v a u w of FEwWmnw
TANK
OR DETLMIW TlYE
FIGURE1. PRODUCTION OF FUELGAS FROM BEER-SLOP WASTE. Based on continuous feeding experiments. feeding, whereby the waste is more thoroughly stabilized, an average of 3 volumes of gas per unit of tank volume can be recovered. DIGESTIOX T.4BLE 111. COMPARATIVE R.4TE.9 O F THERMOPHILIC OF FRESHSEWAGE SOLIDS AND BEER-SLOPWASTE MATERIAL Sen-age solids (6) Beer-slop waste
RATEOF FEEDING (Volatile Matter per VOLUMES OF GAS 1000 cu. ft. Tank RECOVERED PER TANK Volume per Day) VOLUME PER DAY Lbr. 77 1.2
tE
The gas from a tank having a volume twice that of the waste fed each day contains 55 per cent methane and hence has a B. t. u. of 550, which is about the same as that of coal gas (Table 11). The gases from the fermentations carried out in larger tanks (4 to 6 times the volume of waste) contain a little higher percentage of methane (58). This difference in methane content is due to the fact that the volatile organic acids, which tend to remain high in a tank that is being fed a t a high rate, are decomposed if held longer in the digestion tank. These acids give a higher ratio of CH, to CO, (8).
GAS PRODUCTION COSTS On the basis of 50 cents a cubic foot, a 1000-cubic foot concrete digestion tank would cost $500. Such a tank should last from 10 to 20 years. This investment, a t 12 per cent, would mean a yearly cost of $60, or 16.4 cents per day per 1000 cubic feet of tank capacity. The 12 per cent should easily take care of interest, amortization, and repairs. On this basis a tank of twice the volume of the waste to be treated, and capable of delivering 7 times its volume of gas per day, would yield gas of 550 B. t. u. a t a cost of 2.34 cents per 1000 cubic feet. In a tank having a volume 3 times that of the waste (Table 11) more gas will be formed
I N D L S T R I A L -4 \ D E N G I N E E R I N G C H E 31 I S T R Y
January, 1932
per unit of waste, but less gas per tank volume (5.2 volumes of gas per tank volume). This gas could be produced a t a cost of 3.22 cents per 1000 cubic feet. If the industry wanted to stabilize the waste and reduce the putrefactiveness to such an extent that the sludge could be drawn into a lagoon or fill and the liquor run into the sewer or river, it would be compelled to build a tank 6 times the volume of the waste. Then 3 volumes of gas per tank volume would be produced a t a cost, of only 5.48 cents per 1000 cubic feet. TABLE I\i.
COMP.~R.ATIVE COSTSOF Co.4~.N . ~ T u R G4s, .~L DIGESTOR G 4 s FRo\f REER-~LOP ~'.~STE FUEL
AND
1,000,000 B. T. u . Cents Soft coal (12,000 B. t. u.) a t $1.50 per ton.. . . . . . . . . . . . . . 6 . 2 Natural ga8 (1000 B. t. u.) a t 15 cents per 1000 cu. f t . ,. . 1 5 , 0 Digestor gas: From tank, twice volume of waste . . . . . . . . . . . . . . . . . 4.2 From tank, 6 times volume of waste.. 9.4 COST PER
On a heat value basis the smaller tank would partially stabilize the waste and produce gas a t a cost of 4.2 cents per 1,000,000 R. t. u. The larger tank would stabilize the waste and still deliver the fuel gas a t a cost of only 9.4 cents per 1,000,000 B. t. u. These costs compare favorably with those of heat from soft coal, as !yell as with those of heat from natural gas piped from the southwestern states to B. t. u. of heat from soft Peoria, Ill. The cost of ~,OOO,OOO coal having 12,000 B. t. u., a t $1.50 per ton is 6.2 cents (Table IV). 9gaseous fuel always has a decided advantage over a solid fuel. The B. t. u. of gas from the fermentor could be readily increased by washing the gas with n-ater (with or without alkali) under pressure, which would remove much or all of the carbon dioxide. This carbon dioxide could be recovered for synt'hetic purposes or for the production of dry TABLE v. EFFECTO F VARIOUS
tank n a s very fibrous and contained only 70 per cent moisture after having drained S hours on sand. After a 3-day drying (indoors) it had a moisture content of 51 per cent. The dried sludge possessed only a slight odor. The sludge had a I-day biochemical oxygen demgnd (B. 0. D.) of only 615 mg. per 1 per cent of rolatile matter. Rudolfs and Fischer ( 1 1 ) state that a sludge of a I-day B. 0. D. of 1000 to 1500 mg. per 1 per cent of volatile matter is ready to be drawn and will not create a nuisance. The sludge as drawn produced only 44 cc. of gas per gram of volatile matter in 24 hours at 52" C. This is it lower volume than that noted for m o d well-digested mesophilic se!? age sludges (IO).
The overflow liquor from this tank (2-day capacity) was too unstable to be drawn into the open air. It had a n average R. 0. D. of 5700 p. p. m. and contained 2000 p. p. m. of volatile organic acids. Sludge drawn from a tank having a volume 6 times that of the daily volume of waste (6-day capacity) was very stable. It was not as fibrous as that from the smaller tank (2-day capacity). After a n 8-hour draining on sand it had a moisture content of 84 per cent, but after a 3-day drying (indoors) this was reduced to 66 per cent. Its 1-day B. 0. D. per 1 per cent of volatile matter was 357 mg. iis drawn it had only a slight sewage sludge odor, and after drying this had entirely disappeared. The liquors from this tank still had a high 5-day B. 0. D. (3000 p. p. m.). Its organic content (volatile matter) was 3200 p. p. m., but the volatile organic acids were only 200 p. p. m. This overflow liquor contained but 10 per cent of the original organic matter of the waste, and was so stable that i t could be run into the sewer without jeopardizing the operation of the treatment works. This additional load would still keep the organic content of the combined waste within that of normal sewage. In addition to the routine here reported, the fairly stable
r)JGESTION TI\fES
(TANKC4PbCITY) OX STABILITYOF \V.kSTE"
ORIQINAL
FROMTASK,T W C E BEER-SLOP VOL. O F \TASTE (2-D &Y C IPACITY) WASTE Percentage of organic matter gasified 58 Sludge Liquor pH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.0 Total solids, p. p. m... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33,000 Total volatile solids, p. p. m.. . . . . . . . . . . . . . . . . . . . . . . . . . . 30,000 Settleable solids, p. p. m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Volatile acids (as acetic), p. p. m . . . . . . . . . . . . . . . . . . . . . . . . 2,006 Ammonia nitrogen, p. p. m . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 Total nitrogen. D. D. m.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,600 Oxygen conlumkd,'p. m.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16,000 Immediate (30-min.) 2 demand, p. p. m.. . . . . . . . . . . . . . . . . . . .... B. 0. D., 5-day, p. p. m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17,000 B. 0. D., 1-day, p. p. m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6,000 2,400 1,800 1-day B. 0. D . , mg of 0 2 per % volatile m a t t e r . . . . . . . . . . . . . .... 2,000 615 Co. gas per gram, volatile matter in 24 hours.. . . . . . . . . . . . . . . .... 44 Cc. gas per gram. volatile matter in 10 days.. . . . . . . . . . . . . . . . .... 148 .... Moisture in sludge after draining 8 hours, % . . , . . , . , . , , , . , . , 70 .... Moisture in sludge after drying 3 days, % . . . . . . . . . . . . . . . . . . .... 51 Odor as d r a w n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .... Bad .... Odor after 3 d a y s . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Moderate .... Volumes of sludge drawn per 100 volumes of waste f e d . . . . . . . 23 .... 4 Average representative analysis.
6.
....
....
~~~
.... .
.
I
.
ice. The residual gas (methane) could be burned or used in synthetic reGIct'ions.
KASTE STABILIZATION Table V gives representative sanitary chemical data collected during a 7-month small-scale continuous feeding experiment on the gasification and stabilization of Commercial Solvent beer-slop waste. The sludge and overflow liquor from a tank having a volume twice that of the waste fed per day (2-day capacity) was still somewhat unstable, although 58 per cent of the organic matter had been gasified. The sludge drawn from the
35
....
FROMTAXX, 4 TIMES VOL. O F TvAsTE ( & D A Y CAP.4CXTY)
FROXT A N K6, TIMES VOL. OF WASTE
DAY C ~ P A C I T Y )
.6 7
72
Sludge
Liquor
Sludge
Liquor
650 3,000
600 1,000 1,300 150 3,700 1,500
750 3,000
600 850 1000 230 3000 1000
.... ....
4,600 1,500 464 28
83 80 nfbhkrate Slight 22
....
.... 3,200 1,000 357
....
....
....
....
....
.... .... ....
....
.... 84 66
Slight Humur 21
...
...
... ...
... ... ... ...
fibrous sludge could be drawn from a 2-day capacity tank and only the overflow liquor from this small tank given further treatment. This method would require a much smaller total tank volume for the complete treatment of the waste, as the sludge drawn would amount to 23 per cent of the volume of the original waste fed. The volume of the tank for the final 4-day detention of the 6-day period could he proportionately decreased. LITERATURE CITED (1) Aktieselskabet D a n s k Gaerings 284,267 ( J a n . 28, 1927).
Industri,
British
Patent
INDUSTRIAL AND ENGINEERING CHEMISTRY Boruff a n d Buswell, IND. ENG.C H E x , 22, 931 (1930). D a n o k , U . S. Pub. Health Eng. Abstracts, E-919a,120. Hatfield, ISD.EBG.CHEST., 22, 276 (1930). Heukelekian a n d Rudolfs, Sewage W o r k s J . , 3, 3 (1931). M o r g a n a n d Beck, Ibid., 1, 46 (1928). Neave a n d Buswell, IND. EKQ.CHEW.,20, 837 (1926). N e a w a n d Buswell, J . Am. Chem. Soc., 52, 3308 (1930).
Vol. 24, No. 1
(9) P a r t r i d g e , IND. ESG. CHEM.,23, 482 (1931). (10) Pearson a n d Buswell, Ibid., Anal. E d . , 3, 359 (1931). (11) Rudolfs a n d Fischer, Public W o r k s , 57, 171 (1926).
RECEIVED September 10, 1931. Presented before the Division of Water, Sewage, and Sanitation Chemistry a t the 82nd Meeting of the American Chemical Society, Buffalo, N. Y., August 31 to September 4, 1931.
Development of Dakota Lignite VI.
Effects of Blending and Mechanical Pressure on Coking of Lignite
A. W. GAUGER,J. R. TAYLOR, . ~ X DC . W. ULNIEN, Division of Mines and .Mining Experiments, University of North Dakota, Grand Forks, N. D. PRECARBONIZA TION of Dakota lignite temperatures. Thus, a t 815" C. p r o p e r t i e s of Dakota the gas distilled from Dakota 4500 eliminates most of the carbon dioride. lignite is that destruclignite contained 30 per cent carCarbonization of the char from precarbonized t i v e d i s t i l l a t i o n produces a dioxide, as against 43 per lignite mixed with Skelb' petroleum Pifch and residue consisting of a powdery cent a t 550" C.and 62 per cent certain bituminous coals yields a$rm coke. char instead of the a d h e r e n t at 400" C . ( 1 ) . It must be recoke o b t a i n e d under similar membered, however, that the abklechanical pressure during carbonization has conditions from most h i g h e r solute yield of carbon dioxide a markedeffect on the structure ofthesolid residue. rank coals. If a commercially was higher a t the higher temAddition of aluminum chloride hydrate greatly s u c c e s s f u l p r o c e s s of manuperatures, the variation in peraids the formation of a coke residue. facturing a suitable domestic centage being due to the much c o k e f r o m l i g n i t e could be more rapid increase in quantity devised, the development of the vast deposits of S o r t h of combustible constituents with temperature. Dakota would be stimulated by additional market outlets. EFFECTS OF BLENDING The University of Korth Dakota, as part of its work in developing the mineral resources of the state, has been engaged The lignite was crushed to 0.5-cm. size and precarbonized in a study of the carbonization of lignite under different for 1 hour a t 450" C. in an iron retort. The residue was conditions for a number of years. This paper briefly pre- ground t o pass a 14-mesh sieve and kept in sealed Mason sents some of the data obtained during the past three years. jars until required. Table I gives the proximate analysis Gauger and Salley ( 2 ) demonstrated that addition of cer- of the original lignite and the char (450" C.), calculated to tain inorganic materials-notably AlClp.6H20-to the lig- the dry basis. Mixtures were made of this char and difnite before carbonization influenced the process so markedly ferent tars and pitches, the method of mixing being varied that an adherent solid residue,. which they termed pseudo- to suit the material. In every case an attempt was made coke, was obtained instead of the usual powdery char. The to insure thorough mixing. work has since been extended t o a study of the effect of blending lignite, both raw and partially carbonized, with certain TABLEI. PROXIYATE ANALYSESOF LIGNITE.4UD CHAR OY DRYBASIS organic materials for the purpose of producing a domestic VOL.4TILE FIXED B. T. E. coke and a suitable combustible gas. MATTER CARBOX .4sx PER L E . Ordinarily the distillation of lignite yields a gas rich in Original lignite 45 3 47.9 6 S 11,040 450' ohm 19 0 67 7 12.4 12,110 carbon dioxide. It was observed in some other experimental work that carbon dioxide is given off from lignite a t comThe mixture was then formed into briquets in a cupel paratively low temperatures, from which the senior author surmised that it might be possible to remove a large portion of machine and carbonized in an aluminum or nichrome retort, this noncombustible gas by precarbonization a t some tem- depending upon the temperature of carbonization. After perature below that of ordinary low-temperature carboniza- retorting, the residue was examined and the gas analyzed. tion. A study was made of the effect of temperature on the S o attempt was made to obtain tar yields because of the yield and composition of gas from the destructive distilla- difficulty in separating the tar from the water with any detion of lignite. These experiments were carried out in an gree of accuracy. The following materials were tested for effect upon coking apparatus consisting of an aluminum retort, tar condenser, and gas holder with continuous-sampling device. The set- of lignite char: up was essentially the same as that described by Gauger 1 . Bituminous coal-tar pitch. and Salley ( 2 ) . 2. Skelly pitch, consisting of a petroleum residue described by The results which were obtained are represented graphi- Rittman as "Bituminous Coal from Petroleum." The proximate cally in Figure 1. Inspection of this figure indicates that analysis was volatile matter 45 per cent, fixed carbon 51 per cent, per cent (.5). a t approximately 450" C. the ratio of carbon dioxide to total ash3. 4 Illinois bituminous coal, received from S. W. Parr of the combustible gases is a t a maximum. That temperature University of Illinois. This coal swells and blisters badly on was, therefore, selected as the desirable precarbonization carbonization. 4. Red Diamond coal mined in Tennessee. temperature, No attempt was made t o distil at tempera5. Blue Diamond coal mined in Kentucky. tures in excess of 550" C., previous experiments in the School 6. Gold Edge coal mined in eastern Kentucky. of Mines having demonstrated that the gases contained a 7. Wheelwright coal, a gas coal mined in West Virginia and lower percentage of carbon dioxide a t the more elevated used by the local gas company.
0
S E of the characteristic
c.
