US1927968A - Apparatus for carbonizing briquettes - Google Patents

Description

Sept. 26, 1933. E. wlLLsoN 1,927,968

APPARATUS FOR CARBONIZVING' BRIQUETTES original Filed Nov." l, 1928 im EJWLL WSZW@ Patend sept. 26, 1933 UNITED STATES APPARATUS FOR CARBONIZIN G BRIQUETTES Edwin L. Willson, Glenside, Pa., assignor to The Lehigh Coal and Navigation Company, Philadelphia, Pa., a corporation of Pennsylvania 1 claim. (C1. 2ozn This application is a division of my co-pending application Serial No. 316,596, filed November 1,

My invention relates to an apparatus for carbonizing briquettes.

Heretofore, considerable difculty and much annoyance has been experienced with the usual solid-hearth plates used in connection. with carbonizing processes. Such plates deteriorate very rapidly in service and, by reason of their ,relatively large expense, greatly increase the cost of the carbonizing operation. Moreover, when the hearth is replaced, the furnace as a whole must be shut down, with the result'that a further loss occurs. One object of my invention, therefore, is to provide a hearth which overcomes the abovenoted dimculties-my invention contemplating the use of an automatically-renewable porous bed of hot material as a hearth. A bed of this character may be formed of mine refuse having a very low market value.

Other objects and applications of my invention, as well as details of construction and operay tion, whereby my invention may be practiced, will be apparent more fully hereinafter, when taken in connection with the accompanying drawing, wherein The single gure of the drawing is a View partially in section and partially in side elevation of a structure embodying my invention.

Referringv to the drawing, a chamber 1 of a furnace 2 is provided with a passage 3 which extends therefrom through an upper, horizontal side wall 4 to an exteriorly-positioned hopper 5 containing the material to be treated. This material, in one installation, took the form of briquettes, which were first pressed into shape by means not shown and then deposited in the hopv per 5.

In accordance with my invention, the briquette passage 3 terminates in an open end 6 which is positioned just above a fuel bed 7 constituting an automatically removable hearth. The fuel bed '1 is supported on a movable grate surface 8 af,- forded by an upper side 9 of a traveling grate stoker 10. A front end 11 of the stoker 10 extends through an opening` 12 in the front portion of the furnace. bonizing chamber 1 is provided with a fuel-passage opening 14, whereby a carbonaceous fuel 15 such as coke breeze or small sizeof anthracite, may pass. from an exteriorly-positioned hopper 16 through the opening 14 onto the movable grate surface 8, as shown in the single figure of the A front wall 13 of the car".v

drawing. A door 17 serves to control the rate of fuel supply.

The green coal 15, upon entering the chamber 1, is preferably heated to the point of incandescence, the air necessary lto support combustion at this point being at least partly supplied by means of air passages 18, 18 positioned directly under the grate surface. These passages may be supplied with air through ducts 19 which are connected to the passages 18, 18 by 65 tuyres 21. Additional air passages 22, 22 and 23, 23 are positioned under the grate surface 8 and supplied with air through ducts 24 and 25, respectively, so that the fuel bed '7 may assume the general form shown in the drawing, wherein it is noted that an intermediate portion 26 is .formed of incandescent coal, while a rear end portion 27 is formed of hot ashes. These ashes are dropped from an inner end 28 of the stoker 9 into an ash-pocket 29 which is formed be- 75 tween the stoker 9 and a rear wall 31 of the chamber l.

As shown on the drawing, the inner open end 6 of the passage 3 is spaced from the front wall portion 13, so that the briquettes are deposited on the front portion of the incandescent part of the fuel bed '7. The forward movement of the stoker 10 causes the supermposing of a layer 32 of briquettes on the fuel bed 7. While the fuel bed'l, and the superimposed layer 32 of briquettes are 85 moving rearwardly'through the chamber l, the briquettes are heated as a result of direct contact with the fuel bed 7 and the air which passes` upwardly through the porous fuel bed 7 and the layer of briquettes 32. As a result, carbonization of the briquettes occurs and certain of the gases in the briquettes 32 are driven off, mingling with the hot gases passing from the fuel bed 7.

In order that the gases from the heated briquettes may be caused to burn, and thus afford an additionai supply of heat to that furnished by the fuel bed 7, a plurality of air openings 33 may be formed in the carbonizing chamber 1 immediately adjacent to an upper rear wall portion 34 thereof. The burning of the fixed carbon in' l the layer of briquettes is prevented by the control of the amount of air supplied to the 'underside of the fuel bed '7, and to the air openings 33, as well as the control of the rate of operation of the stoker 10. In one installation the rate of l stoker operated was such that a coking period of only thirteen minutes was required. The hot gases formed in the carbonizing chamber 1 may be passed upwardly therefrom through a passage 35 vto a boiler system 36, which serves as an l 'energy-translating means, converting the heat of the gases to steam.-

In operation, assuming the presence of the porous fuel bed 7 on the grate surface 8, as shown in the drawing, movement of 'the stoker 10 results in the' formation of the layer 32 of briquettes. These briquettes, upon being deposited on the fuel bed '7, are heated by conduction due to direct contact with the fuel bed 7 by convection due to the air passing through the stoker110 and the bed 7 thereon, and by radiation from the heat incident to the burning of the gases in the chamber 1. As a result, the briquettes are heated and evolve a gas which mingles with that passing through the fuel bed 7 and burns in the upper portions of the carbonizing chamber 1. When the briquette finally reaches the rear end `28 of the Stoker 9, carbonization to the desired extent has occurred and the briquettes, as Well as the ashes, are passed into the pocket 29 which is provided with a quenching tank 37 in the bottom thereof. The fuel bed 7'thus serves as an .automatic renewable hearth which is formed of material having an exceedingly low market value. Experience has shown that such type of hearth permits an increase in the thickness of the layer of briquettes without sacrificing the uniformity of carboniZatiOn, as compared with the solid type of hearth vheretofore used. Should it be desirable to interrupt the briquetting operation, the energy developed by the boiler 36 may be maintained substantially constant by merelyincreasing the amount of refuse fuel feed to the Stoker 9 from the hopper 16.

While I have shown only one form of embodiment of my invention, for the purpose of describing the same and illustrating its principles of construction and operation, it is apparent that various changes and modications may be made therein, without departing from the spirit of my invention. For example, the porous bed of hot material constituting the hearth may be formed of a non-carbonaceous material, as, for example, sand, and satisfactory operation still obtained. I desire, therefore, that only such limitations shall be imposed thereon, as are indicated in the appended claims or as are demanded by the prior art.

I claim: l

In carbonizing apparatus, the combination with a carbonizing chamber, of a grate, means located externally of the chamber for feeding fuel to said grate, means within the chamber for supplying material to be carbonized to said grate, means for passing a current of air upwardly through said superposed layers to raise combustable gases from saidlayers and to support combustion of said gases, and means for injecting supplementary air into said chamber above the uppermost of said layers for mixing With said gases to stimulate combustion thereof above the layer of material being carbonized. I

EDWIN L. WILLSON.

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