US1810878A - Process of producing an artificial fuel - Google Patents

Description

Patented June 16, 1931 UNITED stares 1? TENT- ems GLENN w. TRAER, or CHICAGO, ILLINOIS, ASSIGNOR T0 NORTHERN LIGNITE-COAL cot v i PANY, or CHICAGO, ILLInoIs, A ooRroRArIoNor DELAWARE rnoonss or PRODUCING An ARTIFICIAL runt 'an artificial fuel and the process of producing the same from coklng coal whose'coking properties have been removed.

The fuel produced is in the natureof what is well known in the art as char, which is a much more desirable fuel for general purposes, and especially in briquettes for domestic use, than high volatile coking coals.

Itis common practice to reduce caking or coking coals to coke by depriving the coking coal of its volatile constituents by heating it in a retort or oven to a degree above its mel ing or fusion point, so that the resultant coke is in a practically common mass and is mainly fixed carbon in a substantially homocellular.

or porous state. But this novel fuel is no coke and such coking is prevented.

The parts of coking coal which cause cokmg n ordinary processes are believed to be bituminous and resinous matters which, when heated to a sufficient degree, partly will volatilize and partly will melt; thosewhich volatilize will pass off and those'which do'not volatilize, unite with the fixed carbon to form thehard cellular mass known as coke. Some of these hydrocarbons will volatilize at lower temperatures than are required to melt and fuse the coal into a mass. It is the, custom in coking practice to subject the body of coal to the highest degree ofheat required for coking as early in the process of heating as is practicable and to maintain the heat at' 'such observedthat Volatilization begins at or about degree throughout the process It hasbeen six hundred degrees Fahrenheit (600) and that melting or fusion begins at or about seven hundred degrees Fahrenheit (7 00). These temperatures have variations for different coals; incipient volatilization appears to begin between 550 F. and 600 F. in various coals and incipient fusion appears to begin at temperatures varying from perhaps 680 F. to perhaps 720 F.

I have discovered that the coking property is eliminated from coking coal if the portion of the bituminous matter which will volati- Application filed June. 15,

I925.- Serial 'No. 373384;

lize at degrees ofheat belowthe melting or fusion point is driven off; and that nielting or fusion will not take place andmass coke will not be" formed from coking coal which has been so treated, even though the coal be then subjected to a sufiicient degree of heat to drive off all recondensable matters. This process requires that in this second stage the coal be heated to a temperatureof approximately 800 to 1100 F. I

A large part of the-bituminous matter which is volatilized in the coking processis recondensable into tar and the remainder passes oif-as fixed gas. That part which is recondens able is the cause of'smoke whenbitumino'us coal is burned in many of the come mon practical methods of combustion. In ordinary methods of combustion, bituminous coking coal to a considerable degree meltsin the firebox, tending to blanket the grate, re-' sulting in: obstructions to tliecirculation of air through the body of fuel and interfering with efficient combustion. f Coking coal which has'been passed through combustion still further promoted.

The object therefore of this invention is to provide an artificial dry, partially volatile and smokeless, fuel and process ofproducing the same.

Other objects of the invention will more fully appear fom the following description and will bep'ointed outinthe annexed claims.

In producing thisartifieia'l fuel there may be employed any ofthe common-forms of ovens or retorts which maybe recognizedly suitable'for the purpose The size of the coking-coal used 'morethan two inches. Internal heat is ap-. le-

higher ranges of heat which would have caused coking except for such prior heat treatment. 'Inother words, this treatment prevents the coking of coking coals. The fuel which has been'so treated is preserved in substantially the same form as it was prior to such treatment. After such novel treatment'of coking coal, the resultant fuel may be heated in the oven or retort'up beyond the coals former fusion point and it will not coke while further smoky and tarry volatiles are driven off so as to produce a substantially non-smoking, non-coking fuel. If desired, such fuel may be ground and briquetted by the addition of pitch and a small percentage of coking coal and/or glutinous matter.

In producing this novel fuel and carrying out this process, a cokingcoal soplaced in a suitable retort or oven is heated to its incipient volatilization temperature. This should be at least six hundred degrees (600) F. as it so has been observed that substantially no'volais the fusionpoint of the coal and it varies as somewhat with the particular coking coals used'but so far as applicant 18 now aware,

such upper limit should not exceed substantially seven hundred degrees (700) F.

The volatilization of the coking coal so heated, between these volatilization'and fusion points, may be observed by the emission of smoke and vapors. p

The periodof time during which the coking coal is maintained between the permissible limits varies with the composition of the dif ferent coking coals from different mines but in actual practice is sufficient to raise the temperature of the coal being treated until the characteristic smoke or vapor is being driven ofi, care being taken-notto permit the temperature of the treated coal to exceed the fusion point, at least until after the cessation of emission of the smoke orvapor while the coal is being maintained at a temperature below the fusion point.

After this new fuel is obtained, it may then i be utilized'as' such; or, it may then be further the fuel and then adding pitch and arelative- 1y small percentage of coking coal and/or characteristic of that temperature range substantially ceases.

2. A process of producing a non-coking fuel. from a coking coal which comprises subjecting the coking coal to a temperature above 1ts 1nc1p1ent volatilization temperature and below 1ts fuslon temperature and mainta ning the coal-temperature between these temperatures until the coking tendency has been practically eliminated. I

a 3. A process of producing a non-coking and smokeless fuel from a coking coal which 9 comprises subjecting the coking coal to a temperature above its incipient-volatilization temperature and belowits fusion temperature and maintaining the coal-temperature between these temperatures until the coking tendency has been practically eliminated;

and then subjecting the coal to a higher degree of heat sufficient so as to drive ofi substantially allthe tarry and smoky volatile substances without causing the coal to substantially change-its form. v 5

4:. A. process of producing a non-coking fuel from a coking coal which comprises subjecting the coal to temperatures substantially .within the range of from600 degrees Fahren- 05 .heit to 700 degrees Fahrenheit, and maintaining the coalwithin this range until emission of volatilessubstantially ceases.

' 5. .A process of producing a non coking fuel from a coking coal which comprises subj'ecting the coal to temperatures not less than i 600 degrees Fahrenheit and not more than 700 degrees Fahrenheit and maintaining the charge .Within this range until emission of volatiles substantially ceases. V a

Inwitness whereof, I have hereunto set my hand this 12- day of June 1925.

GLENN W. TRAER.