US1276427A - Process of treating coal. - Google Patents

Description

I C. H. SMITH.

PROCESS OFATHEATING COAL. APPLICATION miv 1AN.20,191.

Patented Aug. 20, 1918.

kv@ 01N Ik tsm lm Q fr0/mins CHARLES HowAnD sMIrH. or Snom:

HILLS, NEW JERSEY, ASSIGNOR TOl INTER- NATIONAL'COAL PRODUCTS CORPORATION, OF RICHMOND, VIRGINIA, A CORPO- RATION OF VIRGINIA.

' PROCESS 4OF TREATIN G COAL.

Specification of Letters Patent.

Patented Aug'. 20, 1918.

Application led January 20, 1916. Serial No. 73,106.

To all whom t may concern.'

Be it known that I, CHARLES HOWARD SMITH, a citizen of the United States, and a resident of Short Hills, in the State of New Jersey, have invented a new and Improved Process of Treating Coal, of which -the following is a specification.

My invention relates to a new and useful` process of treating solid fuels, such as coal, which soften on heating, and to the resulting products which are recovered from said fuels by the carrying out of said process:

Some of the objects ofmy invention are:

(l) A continuous process of heating coal so as to distil off some of the volatile substances contained therein and change the coal or solidA fuel to a plastic condition; (2) to subject coal to a relatively low heating, thus placing.l in suspension the air, moisture,

gases and vapors which are produced at low temperatures, then carrying the heat to a higher point so as to produce in a state of vapor or gas other substances which do not pass to the state of vapor or gas at lower temperatures, utilizing this property of some of the constituents to dilute and wash out the gases and vapors produced at lower temperatures; (3) to regulate and-control the pressure of the gases within the retort and their passage through the con'densing and purifying apparatus by means of an exhauster; (4) to regulate and control the heat in all parts of the apparatus in which the coal is heated so that the total heat applied during the period of its application is less than the amount required for ultimate destructive distillation during such period; (5) to'prcvent the access of sufiicient air into the retort while the distillation is taking place to produce combustion within the retort and raise the temperature sufficiently to produce coke; (6) to discharge'the residual mass while still in the plastic condition from the retort; (7) to subject the residual mass to a partial compression prior to subjecting it to final compression in order to exclude some of the entrained gases and prevent the occlusion of air when the mass is exposed to the air; (8) to introduce an admixture of either partially distilled coal or coke throughout the plastic material prior to final compression; (9) to lower the temperature of the residual mass by the introduction of this admiXture; (10) to absorb by this unsaturated admixture any remaining entrained gases or condensates within the plastic mass; (11) to then form the entlre mass into briquets; suitable means of conveying the material from the retort to the presses without undue exposure to the the hot briquets to the atmospheric temperature; (14) to recover the by-products from the coal distilled within the retort; (15) to produce a denatured fuel of uniform size approximating 1n physical and chemical quahties a natural coa-l of substantially the same volatile content when compared on an equal ash basis; having a fuel value different from the raw coal or fuel from which it is made'but having substantially the same fuel value as a coal of equal ash and equal volatile content; (17) to produce a substantially tarless vfuel of particular value for certain purposes; to recover some of the more valuable constituents contained in the coal Without reducing its fuel value per pound of fuel by elimination of the volatlle ingredients most conducive to the formation of smoke; and (19) to produce a fuel composed either of coal and partially distilled coal or coke and partially distilled coal.

Heretofore in processes which have been attempted for treating solid fuels such as coal for the purpose of converting the same into briquets, it has been found that the resultant product or briquets have been of little commercial value due to the brittleness of the briquets, thereby militating against their shipment. Such brttleness 1s due to a number of causes such as the compression of entrained gases in the residual niass at the time of compression; also due to the condensation of the volatile substances on the surface'of the individual particles of the residual mass prior to compression, this condensation interfering with coherence between the particles when under compression; also to the imperfect cooling following the briqueting. By my improved process, I remove or eliminate these entrained gases from the plastic heated mass after it passes from `the retort. Some of l2) to providev air; (13) to cool slowly (16) to produce a briquet iro these gases are condensed or driven back into the retort by partial compression, the remainder are absorbed by the introduction of a percentage of either partially distilled coal, or coke, introduced throughout the mass Vand possessing a power of absorbing any entrained gases or condensates remalning in the plastic material as the temperatures of the two materials equalize. then compress'the residual mass into briquets of suitable shape or size without the further admixture of a binder, and properly cool the briquet through the stages subsequently thereto.

rthe process may be best described with reference to an apparatus for carrying out said process, this apparatus and the various steps of the process being illustrated diagrammatically in the accompanying drawing, in which the figure represents a typical apparatus for carrying out the process.

Referring to the drawing B represents a crusher of the usual type adapted to crush or pulverize coal A; C an elevator to elevate the coal to the hopper D; E a spout which feeds the coal to the stoker ld". llihe stoker F is provided with suitable means, such as a plunger for conveying the coal into the retort G, located within the furnace H. The furnace H is provided with means, such as anY arch-shaped heating chamber, below which is located a bed of refractory material and suitable gas and hot air burners, arranged to heat the retort G uniformly.

rllhe retort G is provided with a mixer and conveyer J, located therein, the retort and mixer being so constructed and arranged that the coal within the retort G is mixed, distilled, passed through, and continuously delivered from the retort G. The retort G is connected with the screw conveyer L by the hopper K. rlfhe screw conveyer L is so arranged and constructed that as the partially distilled coal passes from the hopper K through the conveyer L, it first receives an admiXture of either partially distilled coal, or coke, and thereafter undergoes partial compression, for the purpose mentioned above.

rThe plastic coal is delivered from the screw conveyer L to the apron conveyer N through the chute M. ri`his chute is provided with a gate 'lf for sealing off ihe air from entering the retort G at any time that the hopper K and conveyer L are not sealed with plastic material.

rl`he conveyer N is inclosed to prevent eX- posure of the material to the atmosphere and is connected to the feed box 0 of the briqueting press l). As the material passes through the'briqueting press, it undergoes a nal compression, the resulting product being briquets X, which maybe of any desired size and shape. Suitable cooling retratar V means Q are rovided for slowly cooling the briquets as they come from the briqueting press P.

ln order to offset the resistance arising from the passage of the products of distillation through the condensing and purifying apparatus, and to balance the pressure of the gases and vapors within the retort, l provide an eXhauster U connected to the hydraulic main V rlhe retort G should be provided with a dome or riser, which is connected with the hydraulic main V for the receiving of the gases. As the coal in the retort is subjected to gradually increasing temperatures the various gases and vapors developed at the lower temperatures are swept out by the further evolution of gases and vapors produced only at higher temperatures, whereby the procedure may be carried out as a continuous process.

The gaseous pro/ducts and vapors which are given ofi during the heating fof the coal in the retort G pass off by their own pressure to the hydraulic main V, thence they are further conducted by the exhauster and separated by the usual condensing and distilling processes well known to those skilled in this art, into resulting by-products, including tar and oil products l, ammonia 2, benzene and homologues 3, heating gas l and commercial or illuminating gas 5. rlhe heating gas is preferably utilized in my process for heating the retort G.

lin carrying out my preferred process', the coal A is first crushed or pulverized in the crusher B. From this Crusher the coal is fed through the elevator C to the hopper D, thence to the spout E, and then by the stoker F to the retort G in the furnace H. By means of the mixer contained in the retort G the coal is distilled and conveyed through the retort. rThe heating is first at. a relatively low temperature in order to expel the air and any gases, moisture and vapors which are produced at these temperatures. As the coal progresses through the retort the heating is continued to a higher tem perature so as to produce in a state of vapor or gas other substances in the coal which do not pass to the state of vapor or gas at the lower temperatures, and to utilize these additional vapors and gases to dilute and wash out the gases and vapors produced at the lower temperatures. rllhat is, by my process the temperature of the coal is raised progressively as it passes through the retort, thereby making it possible to utilize the properties of these additional vapors and gases to dilute and wash out the vapors and gases produced at the lower temperatures.

lf it is desired to secure fractional distillation, a series of retorts may be utilized, and each of these retorts being heated to a different degree of temperature, so that as the heated coal passes from one retort to the during the period of its application must bel less than the amount required for ultimate destructive .distillation in the same, period.

It is also essential to prevent the access of air to the retort during the distillation in such quantities as will produce combustion sucient to raise the temperature Within the retortto the point Where coking Will take place. Y Y

It will be found lthat the required amount of heating will depend upon the character of the-coal, treated for the reason that different coals must be heated to varying' degrecs vof temperature in order to secure the desired results. j The gases and vapors which are given oli' vwhile the coal is being heated are rich in hydro-carbons. These gases and vapors pass olf from the retort or retorts by their own pressure to the hydraulic main V and the subsequent resistance overcome by the. exhauster U. They are then separated by the usual condensing and distillation processes into gas for illuminating and heating purposes and into tar and oil products, ammonia and other by-products.

After the coal has'been suiiciently heated, it is forced into the hopper K and conveyed from the hopper K b the conveyer L. Duringthis period of trans ation the heated .material undergoes a partial compression with the material, such as and admixture partially distilled coal or coke, in order to exclude and absorb any entrained gases.

The function of the conveyer N is to slightly` further lower the temperature of the residual mass and to concentrate the output of the one or more reto-rts at thefeed box O ready for compression into briquets X.

In the feed box .O the materiall from one or more retorts is suitably mixed and the residual mass fed to the briqueting press P Where it is subjected to the final compression so that the resulting briquet X will be suii'iciently hard in structure for commercial shipment or use.

For further cooling to atmospheric temperature, I have provided suitable cooling means Q so that as the briquets are delivered from the press they will be cooled gradually before, exposure to temperature.

YIn carrying out-my process, I have found the coal Ain a gaseous the air at atmosphericthat the finished product or briquet, which may be o f any desired shape or size, approximates in burning qualities a natural coal having substantially equal ash and equal volatile content. While this resulting briquet has a fuel value di'erent from the.

raw coal from which it is made, .yet it has substantially the same fuel value as raw coal having equal'ash and equal volatile content.

By m duce. a While it tion of the material containing sucient binding qualities for the entire mass. In my process the heat in all parts of the apparatus in which the coal is'heated should be regulated and controlled so that the heat process it is not essential to intromder mto the material before or is being briqueted, the plastic por? applied during the process and the period of its application is less than the amount required for ultimate destructive distillation.

The ultimate percentage of volatile matters or lhydro-carbons can bev controlled Within a considerable range by my process so as to vary thecharacter of the briquets and by-products as desired.

By my process the relative` quantities of -the constituents of the raw coal are changed ,by lpw temperature distillation and limited carbonization, so that the resultant product, after it has been briqueted, is a dense, hard,

,denatured fuel, comparing favorably with coal having equal ash and equal volatile content suitable for commercial shipment. This density and hardness of the briquet are due to the substantial removal, condensation, or absorption of some of the constituents of state, which are either removed, solidified or absorbed prior to bri-- queting, and also due to the reduction to a lminimum of internal strains Within the briquet.

The resultant product, substantially smokeless and tarless,

A. fuels of this character are required.

By the expression ultimate destructive distillation as tial elimination of all the volatile constituentsl of the coal.

While I have described the use of partially distilled coal or coke, as the material to be mixedwith the plastic coal, yet I do notvwish to limit. myself to the use of these materials only, for. my invention comprises the admixture with the plastic coal of any combustible material which has the property of 'absorbing the residual gases and condensates used herein, I mean substan is of particular meritwhere contained in the material extruded from the retort before the same is pressed into the 'form .of briquets. Y

Nor do I Wish to limit myself to the admixture of said materials with the plastic coal after it has passed from the retort, for

1n my process the Icoke, or a material of slmllar characterlstlcs may be lntermixed with the plastic coal at any time after the plastic coal-or the plastic coal residue as 1t may be called-has left the heating zone and carried through the remaining steps of 5 the process, with the same result of absorbing the residual gases and condensates in the plastic material.

What l claim is: l. The process of forming briquets coni@ sisting in eating coal to a plastic condition, removing the coal while in said condition from the heat zone, partiallyv compressing said removed coal and introducing into said plastic coal an admixture of combustible material which will absorb gases and condensates entrained in said plastic coal, and mixing and subsequently pressing into briquets said material while in a heated condition.

2. rlhe process of forming briquets consisting in heating coal to a plastic condition and distilhng gases therefrom, removing the coal residue while in said heated condition from the heat zone, subsequently introducing into said coal while in plastic condition .an admixture of coke to absorb the gases and condensates entrained in said plastic coal and partiall. compressing said removed plastic coal resi ue, and mixing and subsega quently pressing into briquets said heated coal residue and said coke while in heated condition.

3. lThe process of treating coal consisting in heating coal to a plast1c condition, re-

moving it from the zone in which it has been heated, then introducing into said plastic coal a combustible material which will absorb the gases and condensates entrained in said plastic coal, then partially compressing a@ the mass and finally molding it into pressed briquets.

4. The process of treating coal consisting in heating coal to a plastic condition, removing it from the heat zone, then introduca5 ing into it and mixing therewith coke for the purpose of absorbing gases entrained in the coal, then partially pressing the mass and finally compressing and molding the mass into briquets.

l 5. rl`he process of treating coal consisting in subjecting the coal to a series of varying temperatures so that the total amount of heat applied during the successive periods of its application is less than the amount required for the ultimate destructive distillation, removing said coal from the heat zone .and introducing into said heated coal a combustible material for absorbing the gases and condensates contained in said coal,

aat/agar subjecting the mixture to a^ partial compression and ultimately subjecting it to a final compression and molding it into briquets.

6. rl`he process of treating coal consisting in heating coal to a plastic condition and While it is in said condition introducing therein and mixing therewith a combustible material such as coke for the purpose or' absorbing the gases and condensates entrained in said coal and also while in said condition subjecting the coal to a plastic compression, and subjecting the mass when partially cooled to a final compression and molding it into briquets.

7. The process of treatingA coal consisting in heating coal in a manner to distil gases therefrom and until the coal residue is in a plastic condition, removing the coal residue :from the zone in which it has been heated, then introducing into said plastic coal residue a combustible material which will absorb gases and condensates entrained in said plastic residue, partially compressing the mass and finally molding into pressed briquets.

' 8. ln the manufacture of briquets the method which comprises heating coal in order to eliminate some of the volatile material contained in the coal and until there results a plastic coal residue, removing said plastic residue from the heating zone, thereafter mixing therewith material for the purpose or absorbing gases and condensates entrained in said plastic residue and subjecting said plastic residue to a partial compression, and finally forming the resulting mass into briquets by pressure.

9. ln the manufacture ot briquets the method which consists in heating coal in a manner to partially devolatilize the coal and until the resulting residue is in a plastic condition, removing said residue from vthe heat zone and introducing therein and mixing therewith material such as coke for the purpose of absorbing gases and condensates entrained in said residue, subjecting said residue while in plastic condition to a partial compression, allowing the mass resulting from the mixing of the coal residue and the coke to become partially cooled and finally subjecting the partially cooled mass to a final compression during which the mass is molded into briquets.

rThis specification signed and witnessed this 18th day of January, 1916.

, CHARLES HOWARD SMlTH.

Signed in the presence of- G. MGGRANN, W. C. MAReEsoN.

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