US1912245A - Distillation of tar and production of coke - Google Patents

Description

May 30, 1933. I H. H. BAILEY 1,912,245

DISTILLATION 0F TAR AND PRODUCTION OF COKE Filed June 29, 1929 zsneets-sheet 1 Q v S i Q Q Q s; a g

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/9 frMw/a-r 2 Jar I INVENTOR BY v a ATTORNEY-S May 30', 19 H. H. BAILEY DISTILLATION OF TAR AND IRODUGTION OF COKE Filed June 29. 1929 3 Sheets-Sheet 3 I on P Z lease/l" I 11.11611 Iv, a I

Kane aver INVENTOR BY- l ATTORNEYS Patented May 30, 1933 'UNITED STATES PATENT OFFICE- HENRY H. BAILEY, OF CHICAGO, ILLINOIS, ASSIGNOB TO THE BARRETT COMPANY,

OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY ms'rrtm'nox or ran annrnonuo'rlon or con:

Application filed June 29,

etc. into the coke oven during the later period ofthe coking operation whereby the tar is distilled and a coke residue produced, the tar oils being taken off through a separate main and separately condensed and the coke residue from the distillation remaining in the coke oven as part of the coke.

product.

In the operation ofby-product coke oven .plants a battery or block of ovens is operated as a unit, the individual ovens being charged in rotation at regular time intervals. The coking operation requires a considerable period of time, varying somewhat with the type and construction of the oven, the character of coke produced, the operating schedule, etc. The coking operatlon in the individual ovens may require, for example, from twelve to twenty hours more or less. The ovens are heated by heating fiues so arranged as to heat the oven and the charge therein to the necessary coking temperature. At the end of the coking operation the incandescent coke is pushed from the oven and a fresh charge .of coal charged into the incandescent oven. During the early portion of the coking period a relatively large amount of gases is given off and the gases are rich in tar constituents.

During the later ortion of the coking period the volume 0 gas given off from the charge 'is much less and the gases are commonly referred to as .lean gases, being relatively low in tar constituents.

4 The tar produced at by-product coke oven plants is commonly shipped to tar distillation plants to be there distilled to produce merchantable distillates and pitch residues. The pitch residues may be further distilled in a coke still or oven to produce coke there- 1929. Serial No. 374,800.

coke oven plant with utilization of t e coke ovenitself for the distillation. The transportation of the tar to a tar distillation plant is eliminated and the provision of a separate tar still at the coke oven plant is obviated. The distillation is carried out with existing equipment except for the provision where necessary of a separate vapor main and condensing system for drawing off and condensing the vapors and admixed gases from the distillation. The distillation of tar, moreover, can be carried out without the intermediate production of pitch so that only distillate oil, coke and as are produced. By collecting the tar at t e coke oven plant and returning it and distilling it in the coke ovens, according to the presem invention, the entire coke oven plant can be operated, or can in part be operated, so that the tar is utilized and coke, distillate and gas produced therefrom, making unnecessary the sale or shipment or transportation of tar to a tar distillation plant or the provision of separate tar stills or of separate coke stills and eliminating the problem of pitch disposition.

In carrying out the present invention, the coke oven operation is carried out in the usual way during the early portion of the coking period. Durin a later portion of the coking period, pre erabl near, the end of the coking period, tar is introduced into the top of the coke oven with resulting distillation of the tar and the production of distillate oil, gas and coke. The gases produced by the coke oven during the period of tar distillation are drawn off through a separate main which will permit their collection separately from the normal gases given off from the other ovens- That is, the' gases given oil from the ovens during the earl portion of the coking period, and from all top of the incandescent oven it is rapid p at the by-product coke oven plant.

by spraying the same and which are derived from the coking of,

the coal rather than the distillation and coking of the tar.

The present invention is of particulardistillation of coal tar produced Such tar, as ordinarily collected, contains a small percentage of water. Instead of introducing the wet tar into the coke oven to distill it, it may be first dehydrated and the dehydrated tar then introduced into the coke oven to efi'ect its distillation. Instead of distilling tar in the coke oven, the tar can be partly distilled in 'a separate still and the resulting pitch introduced into the coke oven and there further distilled and coked; Other coke-forming residuum can be similarly introduced into the coke oven and there distilled and coked.

The amount of tar produced at a by-product coke oven plant varies somewhat with the kind of coal coked and the conditions of operation of the coke oven plant. It may be, for example, around eight to ten gallons of tar per ton of coal coked which represents around four to five percent by weight of the coal charged. When the tar is part1 distilled and only the resulting pitch in roduced into the coke oven for further distillation and coking, the pitch will value for the represent a correspondingly smaller perby weight of the initial coal charge.

In carrying .out the process, pitch'is introduced into the to oven after the coke has forme therein and preferably near the end 015 the coking opera-. tion. After the coke is formed, the top of the coke and the top arch of the oven are incandescent and when tar is introduced in regulated amount into the top of the" oven itis rapidly distilled and the'residue coked. Similarly when pitch is introduced into tll1e y distilled and coked.' The period during which tar or pitch is introduced can 'be vari'ed with the amount of tar or pitch to be distilled andcokd, the rate of introduction, etc.

The tar or pitch is preferably introduced 7 at a numbercf places so as-to distribute it- It can be in over the incandescent coke. troduced in the form of small streams or 7 through suitable spray nozzles or other devices for breaking up the tar-or pitch and distribu'tin it in the top of the coke oven and over tge of the coke incandescent coke therein. The tar' or pitch will be heated by direct contact with the hot gases escaping through the top of the oven, by direct contact with the coke andby radiation from the incandescent top walls of the oven. The coking of the pitch produces not only coke but also gas in considerable amount. This gas, together with the gas given off from the coal will assist in sweeping the vapors from the distillation out of the oven and into the separate vapor main. If a larger amount of tar is introduced it may spread out in the form of a film over the coke and may rundown through the coke charge to a greater or less extent. The introduction of an excessive amount of tar or pitch should in general be avoided.

In order to collect the distillate from the particular ovens employed for the distillation, I provide a separate vapor main into which the gases and vapors are passed during the distillation period so that they do not enter the ordinary gas main containing the ordinary tar laden gases. In a by-product coke oven plant provided with rich and lean gas mains for separately collecting rich and lean gases, .one of the two mains can be employed in carrying out the present process. In that case, the lean gas main, for example, will be connected to the ovens in which the distillation of tar is being carried out and during the periods of such distillation so that the distillate will be separately collected. The gases from the other ovens and the gases during the early period of cokin when distillation is not carried out will ie collected in the other main and separately passed to the condensing system connected thereto. The distillate from the ovens employed for the distillation, together with the gases from such ovens given off total condensate or heavier and lighter con- I densates by fractional condensation.

The distillates produced by the present distillation mixture wit gases given off will be relatively rocess will be recovered in a tar constituents carried by the from the coal. These gases lean gases and the tar constituents which they contain will be of relatively high gravity. These tar constituents will be recovered-0n cooling thegases and va rs at the same time that the distillate rom the distillation of the tar or pitch is cooled and condensed. The composite condensate recovered from the present rocess will be of a distinctive character.

It the gases and vapors coming from the ovens and resulting from the distillation are directly cooled, the condensates will be tarry oils containing more or less tar constituents,

' tion;

including heavier pitch constituents. By sub'ecting the gases and vapors while at a hig temperature to a suitable cleaning operation, as by a hot pitch scrubber or by an electrical precipitator at a high temperature, the ases and vapors can be cleaned and freer? from heavier pitch constituents and the cleaned gases can then be cooled to recover clean marketable oils therefrom, such as creosote oils, or creosote and tar acid oils, etc.

The distillation of tar, etc., according to the present invention can be combined with the ordinary operation of a by-product coke ovenplant by providing for the introduction of the tar, pitch or residuum during asuitable portion of the coking period and by providing for the separate withdrawal of the gases and vapors during the distillation. The distillation can be carried out in all of the individual ovens of a battery, by providing for'the introduction of tar, etc., during a selected later portion of the coking period, or a part onl of the ovens canbe employed for the distillation. A smaller number of ovens can be employed and a relatively much larger amount of tar distilled in each oven, in which case a larger proportion of pitch coke will be contained 1n the composite coke product at the end of the coking operation.

The coke produced from the distillation of the tar and the coking of the resulting pitch will be combined intimately with the coke produced from the coking of the coal.

If the coking of the pitch takes place only in the u per part of the oven, the composite co e comprising coal coke and pitch coke, will be contained onlyin the upper part of the coke charge. If the tar or pitch runs down to lower levels before it is distilled and coked, the pitch coke may be distributed throughout a greater portion of the coal coke.

The invention will be further described in connection with the accompanying draw-.

lngs which illustrate certain embodiments of'the apparatus of the invention which are adapted for the carrying out of the process of the invention, but it is intended and will be understoodthat the invention is not limited thereto.

Fig. 1 is a plan view of a coke oven battery equipped for carrying out this inven- Fig. 2 is a longitudinal section through one of the ovens of the battery;

Fig. 3 is a section along the line 3-3 of Fig. 2; I

Fig. 4 is a detail in vertical section of Fig. 2; and

Figs. 5 and 6 are a plan view and elevation respectively of a modified form of apparatus.

Instead of providing only a single collector main for collecting all of the gases from all-of the ovens, or instead of providing two mains for separately collecting rich and lean gases, the apparatus shown in Figs, 1 and 2 provides both for the separate drawing ofi of rich and leangases and the separate drawing off of the vapors and admixed gases from the distillation.

In Figs. 1 and 2 of the drawings the coke ovens 5 of the battery are connected through uptake pipes 6 and goose-necks 7 with three collector mains 8, 9 and 10. The collector main 8 is for rich gases, the collector main 9 for lean gases, and the main lOis a vapor main for the collection of vapors resulting from the distillation of tar or pitch within the coke ovens. Each oven-1s connected with each of the mains through an uptake I pipe 6 and a goose-neck 7. Valves 8', 9 and 10 are provided to direct the fiow of gases and vapors from each of the ovens to each of the mains, as desired. The ovens are fordinarily charged in rotation so that the valves will ordinarily be manipulated in rotation to direct the gases and vapors from corresponding periods of the coking operation in each of the ovens to the same collector main.

The ovens are charged with coal through the openings 12. The coal is coked in the ordinary manner and the coke roduced is represented at 13. Flues for heating the ovens are shown at 14. Regenerators 15 alternately are heated by the -products of combustion and heat the air used to burn the gases in the well-known manner.

, The gases in the gas collector mains 8 and 9 are cooled in any usual manner, as by ammonia liquor sprays. liquor are drawn off from these mains into the decanters 16 and 17'. The tar is sepa-- rately collected in the tanks 16 and 17. The gases'from the collector mains are further cooled in the condensers 18 and 19 to separate tarry oils. Tarry oils and ammonia liquor are drawn off from the condensers into the decanters 20 and 21. The tarry Tar and ammonia oils are separately collected in the storage proceeded to a point where a large part of the volatile matter contained in the coal has been distilled ofl, the tar or pitch to be distilled is delivered to these ovens. This may be the tar from the tank 24. It may be supplied to the ovens through the pipes 21,

'WhlCll are connected with the tank 24 by into the collector tank or means of the pump 28 and lines 29. Tar

when no tar is passing through it. For this purpose the pipes 27 are connected with the supply pipes 29 through toggle joints 27'. When not used for spraying, the pipes 27 may beremoved from the oven as indicated in dotted lines in Fi 2, and they may be doubled up and laid Eat upon the top of the ovens. After using they are preferably blown with a fluid, such as steam, to remove all tar or pitch in order to prevent coking of tar or pitch in the pipes and stoppage of the pipes while not in use. After the pipes 27 have been removed from the ovens, the holes through which they enter the ovens are plugged up in any suitable manner to prevent the escape of gases from the ovens and the entrance of air 1nto the ovens. That portion of the pipes 27 which is exposed to great heat may be coated with a protective refractory coating.

The tar is fed to the ovens preferably near the end of the coking operation in each oven. The coke is discharged through the door 31. All or only a portion of the ovens of the battery may be employed for the tar or pitch distillation. The vapors resulting from the distillation of the tar or pitch pass up through the uptake pipes 6 and goosenecks 7 of the selected ovens into the vapor main 10. Connection between each of the ovens and the vapor main 10 through the uptakes pipes and goose-necks is controlled by the valves 10'. The uptake pipes and goosenecks leading to this vapor main 10 are advantageously insulated as indicated at 6' This main 10 may be equipped with spray means for cooling the gases. Distillate condensing within the vapor main is drawn ofi' decanter located at 35 and any uncondensed vapors passed to the condensers 36.

The condensers 36 are here shown as direct condensers. The distillate together with the ammonia liquor which is drawn ofi from the condensers is collected in the decanter 37 and from there the oils are separately collected in the distillate storage tank 38. Distillate from the condensers 36 may be combined with the distillate oils from the vapor main 10, collected in the tank 35, or the two fractions may be kept separate. If a total distillate is desired the condensate from the main 10 together with any ammonia liquor which may be present is collected in the tank 35 and pumped from there by ,the pump '39 through the line 40 to the debe distilled are provided with a second uptake pipe 53 at the rear of the ovens. This uptake pipe connects with a vapor main 54. -Valves are provided at 55 and 56 for directing the flow of the gas so that during the period in which tar or pitch is to be distilled, the gases and vapors will pass to the vapor main 54 and during the remainder or the coking operation the gases will pass to the as collector main 52.

The tar or pitc is supplied through pipes 57'similar to the means shown in connection with the preceding figures. The valve 55 is closed and the valve 56 is opened while the tar or pitch is. sprayed into the ovens. The gases resulting from the distillation of the coal during the period in which the tar or pitch is distilled pass off of the oven through the vapor main 54 together with gases and vapors resulting from the distillation of the tar or pitch.

According to the plan shown in Fig. 5, only a portion of the ovens of the battery are connected with the vapormain. Only those ovens connected with the vapor main are employed for distilling tar or pitch. The gases and vapors resulting from this distillation are collected in the vapor main and ass from the main to a separate condensmg system which is here shown as a single direct condenser 58. From the condenser the gases pass through the exhauster 59 to means for the recovery of ammonia, light oils, etc.

The vapor main 54 is provided with sprays 60 through which ammonia liquor is sprayed into the' gases and vapors pass The resulting partially cooled gases then pass to the condensers 58 where further cooling is efiected and further distillate is the condensers 18, 19 and I 36 pass through the exhausters 41, 42 and 43 Each of the ovens v separated from the gases. The ammonia liquor and distillate from the vapor main 54 are drawn off into the decanter 61. The distillate is then separately collected into the storage tank 62. Distillate and ammonia liquor from the condenser 5-8 are drawn oil into the decanter 63. From the decanter the distillate is separately collected in the storage tank 64.

The gases coming from the ovens .connected with the vapor main 54 during eriods in which there is no distillation o tar or pitch in these ovens and also the gases from those ovens not connected with this vapor main are collected in the gas collector main 52 and treated in the usual manner. They may be sprayed in the collector main with ammonia liquor or they may be cooled by flushing the main with a mixture of tar and ammonia liquor. The partially cooled gases pass through the cross-over main to the condensing system 71 and thence through the exhauster 72 to means for the recovery of ammonia and light oils.

The tar or pitch to be distilled is supplied to the ovens from any suitable source 73.

- n' carrying out the invention the ovens employed for thedistillation of tar or pitch are connected with a vapor main and also with one or more gas collector mains. A single gas collector main may be employed with-apparatus such as that shown in Figs; 1 and 2 and more than one gas main may be employed with apparatus such as that shown The gases and vapors in Figs. 5 and 6. passing through the vapor main may be cooled to separate higher boiling distillate from the gas in this main and then be further treated in a condensing system to separate additional distillate.

It will thus be seen that the present inven-' tion provides an improved process for dis tilling tar, pitch or residuum with direct production of coke and of distillate in which the distillation and coking are carried out as a part of the same operation and as a part of the coking operation at a by-product coke oven plant. The-coke ovens are themselves employed for the distillation so that the pitch coke produced from the distillation is combined w1th the coal coke and so that the distillate from the distillation is recovered in a separate gas handlin and condensing system. With plants w ich are now provided with two separate gas collecting and condensing systems, the present rocess can be carried out with a minimum 0 alteration merely by providing for the introduction of the .tar or pitch into the coke ovens during the selected later portion of the coking period, and with utilization of one of the gas collecting and condensing systems for collecting and cooling the vapors and gases from the distillation to recoverthe distillate therefrom. With plants which do not have two gas collecting and condensingcoke and distillates which comprises introducing a coke-forming hydrocarbon in limited amount into the incandescent upper portion of a .coke oven containing a coal charge which has been at least partially coked therein, and thereby rapidly heating and distilling the hydrocarbon and coking the residue, withdrawing from the coke oven the gases and vapors given of]? during the distillation of the hydrocarbon therein separately from the gases and vapors given off during the coking of the coal prior to such distillation, and separately cooling the gases and vapors to recover cohdensable constit- I uents therefrom.

2. The method of distilling pitch-containing hydrocarbons and of producing therefrom coke and distillates which comprises coking coal in a coke oven until coke has formed from a considerable part of the coal, withdrawing the gases and vapors given off from the coal during such coking and cooling thesame to separate tar therefrom, in-

we I

troducing a pitch-containing hydrocarbon into the incandescent upper portion of the coke oven during a later portion of the cok-' ing of the coal therein and thereby rapidly heating and distilling the hydrocarbon, and coking the residue, separately withdrawing the gases and vapors given off during such distillation, and cooling the same to recover the distillate therefrom.

3. The method of distilling tar and producing therefrom coke and distillates which comprises charging coal to a coke oven and coking it therein, drawing off the gases and vapors given off during all but a later portion of the coking of the coal through at least one collector main and passing the same to a condensing system to recover tar therefrom, returning at least a part of the tar and introducin it in limited amount into the coke oven uring the later portion of the coking of the. coal therein thereby rapidly distilling the tar and coking the residueand separately drawing off the gases and vapors from the oven during such distillation of tar therein, separately cooling such gases and vapors, and separately recovering the distillate.

4. The method of distilling pitch and producing therefrom coke and distillates later which comprises charging coal to a coke oven and coking'it therein, drawing off the gases and vapors given off during all but a p} rtion of the coking of the coal throng at least one collector main and passing the same to a condensing system and recovering tar therefrom, introducing pitch in limited amount into the coke oven during the later portion of, the coking of the coal therein thereby rapidly distilling the (pitch and coking the residue and separatel rawing OK the gases and vapors from t e oven during such distillation oi pitch therein, separately cooling such gases and vapors, and separately recovering distillate. 5. The method of distilling tar which comprises charging coalinto a coke oven'and heating the oven to coke the coal therein, introducing tar into the coke oven after coke has formed in the incandescent upper lportion of the oven before all of the coal as been converted to coke, distributing the tar over the-incandescent upper portion of the coke to bring about rapid heating and distillation thereof and coking of the residue, drawing off the gases and va ors from the oven during such distillation 0 coal and tar, collecting the same separately from gases and vapors given off from the coal prior to the introduction of the tar, separately cooling and separatel collecting the distillate.

6. The method of distilling pitch which comprises charging coal into a coke oven and heating the oven to coke the coal thereintroduoing pitch into the coke oven after coke has formed in the incandescent upper portion thereof before all of the coal has been converted to coke, distributing the pitch over'the incandescent upper portion of the coke to bring about rapid heating and distillation of the itch and coking of the residue, drawing 0% the gases and vapors from the oven during such distillation of coal and pitch, collecting the same separately from gases and vapors given off from the coal prior to the introduction of the pitch to the oven, separately cooling them to condense distillate, and separately collecting the distillate.

t In testimony whereof I afiix my signaure.

HENRY H. BAILEY.

them to condense distillate,-

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