US1901170A - Gasification of carbonaceous material - Google Patents

Description

March 14, 1933. Q KARRlCK 1 1,901,170

GASIFIGATION oF CARBQNACEOUS MATERIAL original Filed oct. 29, i926 La (im JKM JNVENTOR.

fe/aw( ATTORNEYS.

Patented 'Max'. 14, 1.933

PATENT OFFICE LEWIS CASS KAREICK, F SALT aAJiE CITY, 'UTAH GABIFICATIDN 0F CARBONACEUB MATB-IL @riginal application aled october 29, 19% derlei No. 144,647. Divided and .this application tied December itt), 1927.

rlhis invention relates to a process for the production of gas and other products from coal and other carbonaceous material. llt is a division of my application Serial No.

t 144,947, tiled Uctober 29, 1926. 'lhe solid raw material is reduced to a granular or pulverized condition, such as will permit it to be conveyed through a heated tube by a'current of steam acting as a carrier tor the material,

l@ and as a suitable medium in which to heat it terials wherein large quantities of enriched.

Water-gas are formed with a minimum amount ol tars and coke residue. rlFhe process may be operated so as to vary the yield and character or heating value of the gas formed from any given carbonaceous substance, and the gas maybe generated under high pressure.

Advantages are obtained in this invention by the means provided for operating under high pressures, whereby the volatile products are formed under high pressure and the resulting gas may be transmitted under pres- 5 sure to very distant points without the use of compressors. Also by virtue of the pressures used throughout the system, the volatiles may be cooled and condensed in relativelysmall heat exchangers and be caused to give up their contained heat to generate the process steam for operating other units simultaneous- 1y at lower pressures.

According to the present invention prior operating diiliculties in the carbonizing and gasifying of coals, due to their fusibility, low rate of heat conduction, and low reactivity, are overcome to such extent that the coal can be distilled and gasied rapidly regardless of its fusing property or slagging tensemi No. arias?.

dency, or of its tineness, or of the percentage ot mineral matter or ash therein.

llt is Well known that carbon will react with steam when the temperature is high enough and when heat is supplied at the needed temperature in sudicient amounts to produce water gas. According tomy process, coal or coke in granular but preferably in pulverized form is introduced into a heated tube throu h which steam is tlowin so that the coal or co e is carried through t e tube, by the steam, being heated in contact with the steam as it moves through the tube until little or no solid matter is left except ash. When the raw material is coke the resulting gas is that known as blue water gas and this 1s separated trom. any excess steam in a cooler or condenser, after having previously been separated from vthe ash. It is however possible to wash the hot solid material discharged from the heated tube and so to separate solid ash and residual carbon, steam, or other vapors, trom the blue water gas in a sin le step. When coal is gasitied, t e temperature oi the steam may be raised above 1200 F. so as to remove all the volatiles and form some water gas. My process when using colte, is a, continuous Water gas process, producing blue water gas in which the heat required is absorbed by the steam and coke through the tube walls and at temperature high enough and sustained long enough by the heating conditions of the tube. When usingcoal, the volatiles of the coal are added with some decomposition, to the blue water gas formed from the carbon, and the resulting gas is carburetted water gas, the amount of carburation depending on the ratio or hydrocarbon volatile to fixed carbon in the coal and to some extent on its lchemical nature, and on the amount of water gas formed to volatiles contained therein.

When usino c'oal as the raw material, the coal may be iirst distilled and its coke separated in one apparatus, and then the coke introduced into a second similar apparatus operated at higher temperatures, or the two steps of .distillation and carbongasification may be carried out in a single apparatus as seems most expedient.

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with a shell of coke efore the main mass ofV the lump becomes hot enough to soften. The latter treatment prevents neutral dilution of the final gas. VIn all cases whether coal or coke is used an initial heatinglof the solid ma` terial or a superheating of t e steam or both is provided so that there will be no condensa tion of steam as a result of contact. If complete gasification is desired, the final temperatures to which the carbon, coke, and steam, are heated is always high enough and maintained long enough to gasify all or substantiall all of the solid combustible, leaving no soli but ash.

I have used final temperatures from 1350 F. to 1950 F., and have obtained gas of caloriiic values between 250 and 1050 B. t. u. per cubic foot from Utah coal, and 275 and 525 B. t. u. per cubic foot from its coke. I lhave used steam velocities to carry the solid raw material through the tube from 100 to 600 feet per second, and steam pressures from about 100 lbs. per square inch downward preferably withturbulence. The gas is thereby generated at pressures suiiicient-ly high for economical long distance .transmission of the same.

The hot products from the gasifler tubes may be caused to give up their heat so as to yboil Water to make `steam at a lower temperature and pressure and such steam may be used to supply a second or a series of similar gasiers working at lower pressures. A r

The accompanying drawing is a side view with parts in section of an illustrative form of apparatus for carrying out my process: Steam from a source such as a turbine exhaust, an accumulator, or from another coaltreating unit (not shown), is carried by a valved heat-insulated main 34 through a steam separator 35 and past a valve 37 and i into the gasier tube 38 in which the granular or pulverized carbonaceous material is introduced.

Steam from any convenient source enters through the valved pipe 37 into the coil 38 which occupies the annular space between the heat-insulating outer wall 40 and core 41 of a furnace setting. The coil 38 is conveniently heated by products of combustion from burners 42 at the base of the furnace. The 4hot combustion gases pass up around the tubes of the coil, heating the lower part to the highest temperature, and pass off through a stack 43 which surrounds a feed-bini44ffed by a valved magazine 45.

A .feeding device 46 controls the rate at c5 which the raw fuel is fed into the tube. A

the accumulated ash` from dust collector 49.

A well insulated gas outlet 51 is provided by which the gases and vapors may be transi ferred to a condenser or othercoolingelement -52 forming part of the heat exchange device which also serves as van -evaporator. The pressure and therefore the tem erature of the gases and vapors in the condult 51 will be so high, while condensing, that the water in the device 52 yields steam, at lower pressure,.. which may be used in a second coal treatingunit. The condensed vapors, water, etc., together with uncondensed gases'low out of the coil 53 by a valved pipe 54 into a separator 55, without material reduction in pres,

sure. ',Ihe uncondensed gases and any condensates that may collect in the separator 55 may be withdrawn'by means of valved outlet pipes 56. The valves in the pipes 56 alsoV serve to regulate or control the pressure. throughout the system and to provide for delivering gas at high pressure. Instead of connecting the conduit 51 directly to the heat exchange device 52, it may be connected to a lump coal carbonizer so that the hot gases will carbonize the coal aridbecome partially cooled before they pass to the device 52. This is shown in detail in the parent application Serial'Number 144,947.

Coal, coke or other solid carbonaceous fuel in the raw state, or after a previous treat-f ment, is fed through magazine 45 into bin 44 Where 'preheating to any desired temperature is accomplished. The fuel is then fed by device 46, at a predetermined rate as required, into gasiier tube 38 in contact with a stream of steam that is admitted through valve 37, which carries it along and reacts therewith. The suspended or rolling solid particles then move at a high velocity through the tube counter flow to the movement of the combustion gases and into zones of increasing temperature.

I claim:

1. A continuous proces-s for producing wa-la.

ter gas from material such as coal, coke and the like whichcomprises preheating granular particles of said material in a chamber,

.periodically delivering material from the preheated chamberl into a second heating chamber which is maintainedunder pressure,

. and thereafter continuously discharging `said -Inaterial from the second chamber and passvZing' the same at high pressure by means of lsteam in a' generally downward directionV through an externally heated tube of extendmotivo ed length and of restricted cross section at a temperature and period of time sufficient to effect substantially gasification of the carbon constituent of the material, the material while being heated inthe pre-heating chamber being maintained under the workin pressure of the second chamber by the medlum maintaining pressure therein.

2. A continuous process for producing Water gas from material such as coal, coke and the like which comprises preheating granular particles of said material in a chamber, periodically delivering material from the preheated chamber into a second heating chamber which is maintained under pressure and thereafter continuously discharging said material from the second chamber and passing thesame'at a pressure of the order of one hundred pounds per square inch in a generally downward direction through an externally heated tube of extended length and of restricted cross section at a temperature and period of time suicient to eect substantially gasification of the carbon constituent of the material, the material while be ing heated in the pre-heating chamber being maintained under the working pressure of the second chamber by the medium maintaining pressure therein.

3. A continuous process for producing water gas from material such as coal, coke and the like which comprises preheating granular particles of said material in a chamber, periodically delitering material from the pre-heated chamber into a second heating chamber which is maintained under pressure, thereafter continuously discharging said material from the second chamber and passing the same at high pressure by means of steam in a generally downward direction through an externally heated tube of extended length and of restricted cross section at a temperature and period of time sullicient to eiect substantia ly gasification of the carbon constituent of the material, and introducing a scouring material and effecting its passage through said tube.

LEWIS cAss KARRICK

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