US679059A - Process of making coal-gas. - Google Patents

Description

No. 679,059. Patented my 23,. mol. n. s. Moss.

PROCESS 0F MAKING GOAL GAS.

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l No. 679,059.

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ROBERT S. MOSS, OF CHICAGO, ILLINOIS, ASSIGNOR TO L. Z. LEITER, OF SAME PLACE.

PROCESS OF MAKING COAL-GAS.

SPECIFICATION forming part of Letters Patent No. 679,059, dated July 23, 1901.

Application tiled December 17,1900. Serial No. 40,149. (No specimens.)

To all whom, t may concern:

Beit known that I, ROBERT S. Moss, a citizen of the United States, residing at Chicago, in thecounty of Cook and State of Illinois, have invented a certain new and useful Improvement in Processes of Making Coal-Gas, of which the following is a specification.

The usual practice in the manufacture of coal-gas requires in the process the employment of a furnace external to the apparatus where the gas is generated.

The process of the present invention has for its object the manufacture of coal-gas, either illuminating or heating, by the employment of what is known or termed a cokingoven7 of the beehive type without the assistance of any furnace or other heating appliance additional to the oven itself, and the process is of such a nature that by the means employed coal gas, either illuminating or heating, as may be desired, is obtained in addition tothe production of tar and ammoniacal liquor from the coal, as is usual in the manufacture of coal-gas, and these results are accomplished during the operation of coking the coal and without impairing the quality of the coke produced and without the assistance of a furnace or other heating appliance external to the oven.

The invention consists in the several proceedings and steps hereinafter described, and pointed out in the claims.

The carrying out of the process requires the employment of a beehive coking-oven having certain peculiarities of construction, and an oven of this description is illustrated in the drawings, in which- Fignre 1 is a horizontal sectional elevation of an oven adapted to attain the object and purpose of the invention. Fig. 2 is a front elevation showing the body of the oven inA dotted lines back of the front protecting-wall of a battery of ovens; Fig. 3, a vertical sectional elevation showing an oven adapted for use in carrying out the process and provided with a flue for heating the bottom of the oven with the waste consumed gases Fig. 4, a horizontal sectional elevation on line 4 of Fig. 3, showing the heat passage or channel in the bottom of the oven Fig. 5, a detail in section showing the construction of the bottom of the oven of Figs. 3 and 4, and Fig. 6 a detail in cross-section ofthe bottom ot' the oven of Figs. 3 and 4.

The drawings, with the exception of Fig. 2, show only a single oven; but it is to be understood that either a single oven or a battery of ovens can be used in connection with the process, and with a battery of ovens the ovens which constitute the battery are to be suitably connected together, as is the custom with the construction of coke-ovens arranged in series of battery form.

The oven is of the general type of what are known or termed beehive coking-ovens, and, as shown in the drawings1 this oven is formed with a wallA and a bottom B, inclosing a coking-chamber C. The coking-chamber has external air supplied thereto to support combustion and to produce an intense heat by means of apertures or openings D, arranged in the wall A at different points, each with an inclination in dierent directions, so as to produce a circulating blast through each aperture or opening, and, as shown, the apertures or openings have an upward inclination, so as to insure the carrying of the blast over the mass or charge of coal in the coking-chamber. The external air is projected through each aperture or opening from a nozzle or discharge-pipe D', entered into the aperture, and each nozzle or discharge-pipe is connected with a common supply-pipe D2, receiving a supply of air through a pipe D''from any suitable source of supply that will cause the air to be supplied to the pipe D2 under pressure. The top ofthe oven has therein the usual trunnel-head E, with its charging-opening, and at one side the wall is provided wit-h the usual opening F for withdrawing the coke.

The bottom of the oven has therein on each side of the center a channel or passage G, each extending, in the arrangement shown, diagonally from the front toward the rear of the oven and each having its top provided with perforations or slots which open into the coking-chamber beneath the mass or charge of coal when in the chamber. Each passage or channel extends through the front wall of the oven and has connected therewith a pipe H, which leads to and is .sealed in a hydraulic IO manuel.

main (not shown) in the usual manner of ening the temperature, and at the same time the tering and sealing pipes in the hydraulic main for gas apparatus, and each pipe H has a controlling-valve for opening or closing the pipe, as may be required. The coking-chamber has in the wall thereof an opening into which the end of a pipe l leads, which pipe is extended to the same hydraulic main as the pipes l-l and is sealed therein in the usual The channels'orpassages G, with their conducting-pipes H, furnish the means for withdrawing the gas and products of coking, such as tar and ammoniacal liquid, from the bottom or lower portion of the cokr5 ing-chamber, and the pipe 1 furnishes the means for withdrawing the gas and products of coking from the top or upper portion of the coal, so that in operation the gas and other distilled products will be drawn by one educzo tion or the other from the entire mass or charge of coal.

It is desirable in employing the process t0 furnish a uniform heat throughout the mass or charge from the top to the bottom thereof,

and an arrangement for this purpose is shown in Figs. 3 and 4, in which a flue J is formed with or attached to the wall of the oven, with its mouth openingl into the coking-chamber, at the top thereof, and its lower end commu- 3o nicating with a passage K, formed in the bottom of the oven, by means of vertical partitions, each alternate partition terminating short of the wall of the oven, so as to leave an opening at its end, forming a sinuous or zigzag passage or channel for the heat to travel beneath the coking-chamber and finally discharge at a iue L, the lower end of which communicates with the bottom passage or channel for discharging the gases car- 4 4o ried through the bottom into the atmosphere,

and this discharge-flue can be formed with or attached to the Wall of the oven. The flue J is controlled by a damper M, the stem or handle of which extends through the wall of the oven, so that the damper can be moved or turned to have the flue opened or closed, as required. The consumed gases at the upper portion of the coking-chamber are of a high degree of heat, and these gases are 5o drawn into the mouth of the Iiue J when the of the high heat of these gases the bottom-ofthe coking-cbamber becomes highly heated from the passage of the gases therethrough, and this highly-heated bottom acts upon the bottom or lower portion of the mass or charge 6o of coal, imparting heat thereto, which heat acts to evolve and expels the gas and volatile matter from the bottom of the mass or charge forsuch evolved and expelled gases and volatile matter to pass upward through the mass or charge and mingle with the air-blast projected into the coking-chamber, increasing combustion and as a necessary result increasoperation of evolving and expelling the gases and volatile matter is conducted throughout the entire charge or mass of coal instead of at the upper portion thereof, as would be the case with a cool bottom instead of a hot bottom for the coking-chamber.

The @cking-chamber is supplied with the charge or mass of coal to be coked through the trunnel-head E, and when the charge is entered into the coking-chamber the front of the oven is sealed and the trunnel-head left open, as usual in the operation of coking coal. After the coal ignites a blast of air suflicient to create complete combustion and produce a distillation of the coal is entered into the coking-chamber, and when a sufticien tly-high temperature has been obtained the supply of air is shut off, the oven is made gas-tight, damper M is closed, the proper gas-valve is opened, and the products of distillation collected in the manner hereinafter set forth. rI he blast of air can be entered through the openings D in the coking-chamber above the mass or charge of coal or be entered into such chamber through suitable supply pipes and openings or perforated ovenbottom at the bottom of the mass or charge; but in either case after an air-supply of the requisite amount to raise the temperature sufficiently high to produce distillation has been entered the supply is to be shut o.

The process of withdrawing the gas and distilled products is carried out through the eduction channels or passages in the bottom of the oven or through the eduction-pipe l, which is situated just above the mass of coal in the oven. The lower eduction passages or channels and their connecting-pipes on the bottom are employed when the ignition and combustion is from above, which will be the case when the air-supply is admitted into the upper portion of the coking-chamber,in which case the gas and the distilled products are ,drawn down through the mass or charge of coal into the eduction passages or channels to enter the pipes and be discharged into the hydraulic main for further treatment, as is usual in the production of coal-gas. The upper eduction-pipe I is employed when the airsupply for combustion is entered at the bottom of the coking-chamberin which case the ignition and combustion will be from the bot- -tom, and the coal-gas and distilled products Will be drawn upward to pass out through the upper pipe and enter the hydraulic main for tom of the. mass or charge of coal; but it is to be understood that for some purposes and lwith som'e kinds of coal either one or the other of the air-supplies alone can be employed, as best adapted for the treatment of the coal, and this can be determined upon IOO IIO

IIS

from the nature of the coal by an analysis and from its physical properties. The process embodies the principle of heating either the top or bottom layer of the mass or charge of coal to a fairly-high temperature, then shutting oic the air-blast, closing up the oven, making it gas and air tight, and then by opening the valve of either the eduction-pipes H or the eduction-pipe I connecting the oven with the hydraulic main to withdraw the products of distillation from either the top or bottom, according as to whether the distillation of the coal is at the top or bottom layer thereof. If the combustion, before making the oven gas or air tight, takes place at the upper portion of the mass or charge, the eduction of the gas and distilled products will be from the bottom of the mass or charge through the passages or channels and their pipes; but if the combustion, before making the oven gas or air tight, takes place at the bottom of the mass or charge the withdrawal of the gas and distilled products will be from the top through the eduction-pipe I, aud such distillation will continue in either case so long as the walls of the oven retain a sufficient amount of heat to produce the required distillation. It will be understood that the distillation will continue for a longer or shorter period of time, depending upon the heat retained by the walls of the oven, by the heat of the layers of coal, by the readiness with which the volatile matter is evolved and expelled, and also by the amount of volatile matter contained in the coal under treatment, and upon these conditions also will depend the period of drawing off the gas and distilled products before renewing the charge of air for further treatment of the coal.

The combustion of the coke on the bottom of the oven should beprevented after the whole of its volatile matter has been expelled and it is found necessary to admit ai'r through the bottom, so as to increase the temperature in the interior of the mass of coal, and for this purpose the products of combustion from the top of the oven can be returned to the bottom and there mixed with the air, thus diluting the oxygen of the air to such an extent as to prevent combustion of the fixed carbon, while it will readily consume a portion of the volatile matter in the interior of the mass or charge. By this means the temperature of the interior of the mass or charge is raised sufiiciently high for the continued distillation of the layer of coal above it. The air-supply is then shut off, the oven made gas or air tight, the upper eduction-valve opened, and the products of distillation are drawn off.

When the temperature has fallen below the point of distillation, the proper eduction valve or valves is or are closed and the oven is again opened up and recharged with a blast of air to produce rapid combustion, thus again raising the temperature of the coal. In so doing it may be well to reverse the blast-that is to say, if in the first operation the air was blown in at the top of the coking-chamber the next operation should have the air blown in at the bottom of the chamber, and, if necessary, the bottom of the chamber can be heated by opening the flue J, so as to supply the bottom of the oven with heat from the highly-heated consumed gases. It will be understood that when the necessary supply of air is projected into the chamber either at the top or bottom, the supply is to be regulated in proportion to the evolved volatile matter expelled from the coal, thus again bringing it into a condition for rapid distillation, and the evolving of gases and volatile matter to be again drawn off until the temperature falls below the point of distillation. The gas, tar, and distilled liquors should preferably be made to pass off through the eduction passages or channels in the bottom of the oven when the air-supply is entered at the top, and when the air-supply is entered from the bottom the gas, tar, and ammoni'a'cal liquor should preferably be made to pass off from the top, as by this arrangement the heavy gases do not pass through a hot layer of coke or coal, which would crack them up into lighter gases, thus reducing the illuminating power by deposition of carbon. The process of alternately drawing the gas and distilled products from the top and bottom of the mass or charge is continued until the entire mass or charge has been operated upon, when the resultant product will be a coke of a high degree of efficiency, it being understood that after the entire amount of gas and distilled liquid which can preferably be expelled is drawn o, leaving only sumcient for coking the coal, the remaining portion of the charge or mass is to be treated by leaving the oven open for the admission of the air-blast, if necessary, and so proceed with the coking until completed. If care is taken not to withdraw too much of the volatile matter from the coal before proceeding with the final coking process, the resultant coke will be equal to and in some cases superior to that obtained in the ordinary process of coking, and this coke will be in addition to the gas, tar, and ammoniacal liquor obtained by the operation of theprocess in the production of gas.

My process operates to withdraw in an unconsumed condition all volatile matter which is not necessary to the production of heat for the operation of coking the coal, and in use the heat of combustion and of the oven is utilized to throw off the volatile matter to an extent only that will leave a remainder sufficient to continue the production of coke from the coal, and the volatile matter thus thrown off is collected in the form'of gas, tar, and liquor and withdrawn through the eductionpipes and delivered to the hydraulic main for such further treatment common to the production of coal-gas as may be necessary. The result of the process is the obtaining of a IOC IIC

good quality of coke and in addition thereto the saving of the volatile matter which heretofore has been wasted in the production of coke. It is well known that in the treatment of coal for the production of coke there is always a considerable margin between the to tal heat represented by the combustion of the volatile matter and the heat necessary to coke, and it is this dilerence which is saved by the use of my process. It is also well known that only a very small quantity of the heat generated in coking coal and obtained from its volatile matter is made eective. It is this waste volatile matter which is utilized and rendered effective in my process, thus sayin g a large portion of the total volatile matter in the form ot' gas and tar,with the nitrogen in the coalsaved in the form of ammoniacal liquor. The amount of gas, tar, and liquor obtained per ton of coal coked will depend upon the amount of volatile matter in the coal, its facility for coking, and the temperature at which the Volatile matter is evolved and eX- pelled; but in any case a greater or less amount of gas, tar, and liquor will be produced and saved bythe employment of my process.

When it is desired to obtain producer-gas,

4my method or process is used by blowing air into either the top or bottom of the mass or charge of coal, such air being regulated so as to insure a partial combustion of the volatile matter in the coal, at the same time drawing olf through the e'duction pipe or pipes the consumed gases, together with the unconsumed volatile matter. This drawing oft' is reversed from time to time, the air being blown in at the bottom and the gases taken off through the upper eduction-pipe, afterward blowing air in the top and drawing the gases oft through the lower eductionpipes, and this plan of an upper and lower blast and reverse drawing oft is continued for such length of time as is necessary without'injury to the fixed carbon. The length of time necessary can only be determined from the nature and properties of the coal, its amount of volatile matter, and the rapidity of its expulsion under varying degrees of heat. The volume of gas obtained and its heat units per cubic foot can by this process For instance, if the operbe Varied at will.

ation is conducted at a llow temperature, less gas will be obtained, the heat units of which per cubic foot will be very high,and more tar than when operated at a higher temperature. At a very high temperature a large volume of gas will be obtained, the heat units of which per cubic foot will be very small, and no tar. Between these extremes by my process gases of almost any degree of heat per cubic foot can be obtained. The maximum amount of heat which it is possible to Obtain per cubic foot of gas will depend upon the amount of volatile matter inthe coal and the manner of operating.

By the use of my process there can be obtained at will a gas very high or very low in heat units, thus giving a greater range and that, too, in a much more simple manner than has heretofore been possible with any other process. v

What I claim as new, and desire to secure by Letters Patent, is

l. The process of producing coal-gas, which consists in charging a beehive coking-oven with coal, admitting air to the coking-chamber of the oven to produce combustion and heat the walls of the oven and the charge or mass of coal, making the oven gastight, after closing the air-supply, forthe heat to distil the gases and volatile matter, and alternately educting the distilled gases and products from the top to the bottom layers of the charge or mass of coal, substantially as described.

2. The process of producing coal-gas, which consists in charging a beehive coking-oven' with coal, admitting air to the coking-chamber of the oven to produce combustion alternately at the top and bottom ofthe mass or charge of coal, and heat the walls of the oven and the charge or mass of coal, making the -oven gas-tight, after closing the air-supply,

for the heat to distil the gas and volatile matter and educting the distilled gas from the bottom when the combustion is at the top of the mass or charge of coal and from the top when the combustion is at the bottom of the mass or charge of coal, substantially as described.

ROBERT S. MOSS. Witnesses:

THOMAS A. BANNING, OsoAR W. BOND.

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