US1675687A

US1675687A - Coking retort oven

Info

Publication number: US1675687A
Application number: US426415A
Authority: US
Inventors: Becker Joseph
Original assignee: Koppers Co Inc
Current assignee: Beazer East Inc; Koppers Co of Delaware
Priority date: 1920-11-26
Filing date: 1920-11-26
Publication date: 1928-07-03
Anticipated expiration: 1945-07-03

Description

July 3, 1928.

J. BECKER COKIN@ RETORT OVEN Original Filed Nov. 26. 1920 5 Sheets-Sheet NNN.

J. BECKER COKING RETORT OVEN July 3, i928. 1,675,687

original Filed Nov. ze. 1929 5 sheets-sheet 2 Jury 3, 192s. 1,675,687

J. BECKER COKING RETORT OVEN Original Filed Nov. 26. 1920 5 Sheets-Sheet 5 Pl/SHEH. COKE.

July 3, 1928.

J. BECKER COKING RETORT OVEN Original Filed Nov. 26. 1920 5 Sheets-Sheet .mw ...mm .w to obwh.

July 3, 1928. 1,675,687

J. BECKER COKING RETORT OVEN Original Filed Nov. 26. 1 'gs-Sheet 5 Patented July 3, 1928.

UNITED vsTaTEs PATENT OFFICE.

JOSEPH BECKER, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 THE-KOPPEBS QOH-4 PANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION 0F PENNSYLVANIA.

coxme nnronr ovEN.

Application filed November 26, 1920, Serial No. 426,415. Renewed June 18, 1926.

This invention contemplates improvements of general utility in the coking retort oven art, and of especial utility in coking retort ovens of the well known Koppers crossregenerative type exemplified'in Athe patent to H. Koppers No. 818,033 dated April 17,

The invention has foran object the provision of va coking retortoven having, as an important characteristic, a ready adaptability for operation with producer gas as the oven fuel, and constructed, so as to insure delivery of the entire volume of the producer gas supplied to the flame flues in which the gas is burned and to prevent waste of producer gas.

In addition to the general objects recited above, the invention has for other objepts such other improvements or advantages-in construction and operation as are found to obtain in the structures and devices hereinafter described or claimed.

, In the accompanying drawings, forming a part of this specification, and showing for purposes of exemplification a preferred form and manner in which the vinvent-ion may be embodied an'dp'ra'cticed, but without limitingthe claimed invention to such illust-rative instance or instances:

Figure 1 is a composite vertical'section and elevation of a cokng retort oven lembodying features. above specified and equipped with thev improvements of the present invention, the sectional portion of the figure being takenon vertical planes longitudinally of the oven battery indicated by the lines D-D, F-F, E-E and GG of Fig. 2;

Fig. 2 is a vert-ical section taken transf versely through a heating wall of the coking retort oven;

Fig. 3 is a vertical section taken transversely through av coking chamber 'of the coking retort oven; A

Fig. 4 is an enlarged fragmentary top The same characters of reference indicate the same parts in each of the several views of the drawings.

In its present embodiment,` the invention is incorporated in a small coking plant, having features of the well known Koppers cross-regenerative type, exemplified in `the patent to H. Koppers hereinabove mentioned and in my prior' Letters Patent of the United States for coking retort oven No. 1,416,322, dated May 16, 1922. My said prior patent relates to a cokingretort oven having an extreme flexibility in operation exemplified in a ready adaptability of the oven for operation either with producer g'as as the fuel or with coke oven gas burned in an atmosphere of ordinary preheated air, such as is utilized in ordinary coke ovens, or with coke oven gas burned in an ,atmosphere containing both air and aneutral gaseous diluent which is introduced into vthe combustion flues separately from the air. lBecause `of the adaptability ofthe coke oven of my said prior patent for operation with'producer g'as as a fuel, the present invention is incorporated in such an oven, in which' the invention is of particular utility. For conveniencethe present description will be confined to this use of the invention; features of construction and operation are, however,

readily susceptible of other valuable appli-v cations; con'sequently the seop'e of the in-r. vention is not confined to the .specific yuse andl specific embodiment hereinafter described as Aan illustrative example. i

Referring to the drawings: there are illusr trated sectional views of a coke oven battery or plant ofthe by-product type, such as has been hereinbefore mentioned, which coke oven battery embodies in its construction a plurality of crosswise elongated heating walls 11, 11 and a plurality of intermediate crosswise elongated vertical chambers or

ovens

12, 12. The heating walls 11 form the side-wallsof the respective coking chambers l12, as shown more particularly in Fig. 1, and in the present instance are supported by the heavy supporting or pillar walls 13,- 13, extending crosswise ofthe battery and located,- as shown, beneath the respective heating walls 11.

firmly supported upon a flat mat `or platform 14 which constitutes the sub-foundation on which the entire battery rests.

The coal to be coked is charged into the several coking chambers orotfens 12 through charging holes 15 located in the top 16 of the oven `battery and positioned directly above theovens or chambers 12, as shown in Fig. 3. These chargin holes 15 are equipped with the usual remova lefcovers, which -re removed during chargin of the sev al ovens and placed in pesition to close the tops of the ovens during the entire coking operation. f V v Heat for coking the charges of coal in the several ovens or chambers 12 is derived from the heating walls 11, which, as before men-4 tioned, extend crosswise of the battery at` the sides of the coking chambers. In the A angular flues. Hence, a detailed description of the flue construction is not essential to the present specification.

The crosswise regenerators 18 of the battery are located 'at a lower level than the aforesaid heating walls 11 and coking chambers 12, and, in the resent instance, extend beneathl the coking chambers 12 and between the illar walls 13. Below the middle lengt wise line of the heating walls, there is a partition 19, shown more particularly in Figs. 2 and 3, which extends all th way up :from the mat of the battery to the bottom of the overlying coking chamber and from one to the other of the pillar walls 13. With this construction, there are thus formed below each coking chamber and crosswise of the batte two end to end regenerators 18, the meeting ends of which are the partition 19 above mentioned.

Each regenerator 18 is a chamber containing open brickwork commonly called checkerwork and indicated at 20, wlth a'distributing s ol'channel 21 underneath the checker-- .work of each regenerator, the Vchannels 21 forming the lsoles of such chambers and openingup into the checkerwork of their respective regenerators. These regenerators in alternation are heated b the hot combus- V tion products that are ex austed from the f flame or combustion flues herenbefore mentioned and then impart such'heat to the meg dium that they feed into these flame flues, the preheated medium so fed into the ame flues varying in accordance with the character of oven operation, as will hereinafter a ar.

p 'n' accordance with the present embodiment of the invention, the sole channels 21 of the regenerators on both sides of the longitudinal partition wall 19 extend from y.

.of the regenerator on the far side of the partition wall. 4

The reversal in direction of flow through the several regenerators of the battery, and also through the flame or combustion fiucs 0f the heating walls with which the regenerators communicate, takes place crosswise of the battery in accordance with the mode of operation employed in the patent to Koppers above mentioned, ForV example, all of the regenerators 18 on one side of the partition v19 operate concurrently as inflow regenerators, while all of the -regenerators on the other side of the partition 19 are operating concurrently as outflow regenerators, and this is true notwithstanding the medium introduced into the several regenerators. On reversal, by means of the reversing devices hereinafter mentioned, all of the regcnerators on the far side of the aforesaid partition 19 become inflow operating regenerators, while, at the same time, all of the regenerators on the near side of the said partition become outflow operating regenerators.

Each ue 17 of each heating wall has at itsgtopa port or opening 22 for draft and the passage of combustion products or waste gas from the flames within the flues. These por-ts 22 open* up into horizontal fiues 23 formed in the heating walls and connecting all the flues on the pusher side of their re- Bpective heating walls with all the flues on t ecoke side of said heating walls.

'In the operation of the battery, the several flues on one side of the longitudinal dividing' line L operate as upburning fiues, while concurrently the several flues on the other side of such dividing line operate as downburning or exhaust flues, the several flucs 0n each side of such dividing line exchanging functions on reversal of the oven. The horizontal channels or bus flues 23 just men- -tioned serve to direct the exhaust gases issuing from the ports 22 of the upburningr ues into the similar ports of the ldowniburning fiues on the opposite side of the longitudinal dividing line. The draft through the ports 22 may be regulated byY means of the usual movable dampers or sliding bricks 24, positioned in the ordinarv way in the Iitlv .bottoms of the horizontal flues 23 and adapted to be'reached by access lues 25 ,which extend from the top of the channels 23 in each heating Wall to the top 16 of the battery, there being an access flue positioned over each flame or combustion flue of each heating wall. Extending crosswise of the battery in each pillar wall 13 and located beneath the heating wall 11 thereabove, is a pair of gas supply channels 26 and 27, the channel 26 being located'above the channel 27, as shown in Figs. 1 and 2. These channels 26 and 2 7 are for the purpose of supplying coke oven gas to the several flues on each side of the dividing partition L, and for this purpose, the channel 26 communicates with the-individual flues 17 on the pusher side .of the dividing line L by means of ducts 28 that lead from such channel 26 individually into the bottoms of individual flues; and the channel 27 which supplies the several fines 17 on the coke side of the dividing line L communicates therewith by means of /similarly connecting ducts 29. Within the several ducts 28 and 29 are disposed the usual nozzles 30.

The supply of coke oven gas to the channels 26 and 27 of the respective heating walls 11 is derived from a coke oven gas main 31 located, in the present instance, on the push= er side of the battery, as shown'in Figs. 2, 3 and 5, and extending longitudinally therealong. VA series of supply connections, designated generally by the reference character 32 and conveniently of the general nature and arrangement disclosed in my before mentioned prior Patent No. 1,416,322, connects the coke .oven gas main 31 with the several pairs of channels 26 and 27. A detailed description of the construction of such supply connections 32 is not thought to be 4necessary in the present specification and it will be sufiicient to state that said supply connections 32 embody mechanism which operates, at each periodicreversal of the battery, to admit a supply of coke oven gas either to all of the channels 26 or to all of the channels 27 and to turn off the gas from the others. For example, while the channels 26 are receiving a supply of gas from the main 31, the channels 27 are shut oil' from such main and viceversa, in accordance with reversal in direction of flow through the llues 17. as hereinbefore explained.

The ducts by which the several regenerators communicate with the lues 17 are in their general arrangement similar to those disclosed in my prior Patent No. 1,312,301 dated August 5, 1919 and the prior patent to Joseph van Ackeren No. 1.312,372 dated August 5, 1919. `Each regenerator communicates with the corresponding flues of the two heating walls adjacent to such regenerator by means of forked regenerator ducts 33, each extending first obliquely and then vertically up into the heavy wall pillar 13` and positely facing contiguous flues. These twoV branches of such forked duct become substantially vertical under the flue into which each becomes a port, and are so offset from the main channel ofthe duct, at its place of forking F, as to equalize the regenerator lo'w from such channelpinto and through such branches of the fork.

Referring now m'ore particularly to Figs. 2, 3 and 4, the sole channels 21 of each pair of regenerators positioned endwise beneath a coking chamber respectively communicate with air ducts located, according to the present embodiment of the invention, on the pusher side of the battery, that is to say, the sole channel 21 of each regenerator on the coke side of the partition 19 communicates with a flow box 36, and each regenerator on the pusher side of the aforesaid longitudinal partition 19 communicates with a flow box 37; this results in the arrangement of two series of flow or

air boxes

36 and 37 along the pusher side of the battery,u the air box of the series 36 being respectively in communication with the pusher side regenerators and the air boxes 37 being respectively in com- Amunication with the coke side regencrators.

The several air boxes of the series 36 are provided with lids 38 for opening and closing the interior of the respective air boxes to the outer air, and the several air boxes of the series 37 are provide-d with similar lids 39. Each air box lid 38 is provided with a lid-operating lever 40 and each air box lid 39 is provided with a similar lid-operating lever 41. As shown in Fig. 4, the several air boxes ofthe series '36 are disposed in alternation with respect to the several air-boxes of the series 37 and, as a result of this arrangement, the air boxes may .be grouped into pairs, each pair comprising an air box 36 and an adjacent air box 37. The lidoperating levers 40 and 41 to alternate pairs H of such air boxes are controlled and operated by a single cable 42, whereas the lid operatlng levers 4() and 41 of the pairs K of the air boxes that are intermediate such alternate pairs of air boxes aforesaid are controlled and operated by a single cable 43.

The

cables

42 and 43 are respectively provided With stops 44 and 45 suitably positioned therealong for engaging and operating the several levers 40 and 41 which they control,y such stops being adapted on movement of the cables in one direction to engage certain of the aforesaid levers and operate them, While concurrently releasing other levers permitting the coresponding air box lids to yremain in or be'returned to closed position. Both the cables 42 and 43'are -movable into three positions, i. e.. into' neutrah right and left positions. When eitheriof the

lUU cables

42 and 43 are in neutral position` the lids of all the air boxes that such cables control are in closed position. The operation of one of the cables to its left position, for example the cable 43, results in the opening of the lids of alternate air boxes of the series 36, whereas the lids of the series 37 that are controlled by such cable remain in closed position. Conversely, on movement of the same operating` cable 43 toward the right, the lids of such air boxes of the series 37 as it controls are opened and the previously opened lids of air boxes of the series 52 are permitted to close. The other cable 42 controls the pairs of vair boxes H, in exactly the same manner as has just been described. Consequently, by operating both cables simultaneously in the same direction all of thc air boxes of either

series

36 or 37 may be opened, this depending on whether the cables are moved to the right or left positions. Either cable, however. may be operated independently of the other and as each cable controls only alternate pairs of air boxes, the operation of one cable to right and left positions, while the other cable remains in neutral position, would result in opening the lid of onlv every fourth air box while the lids of all the other air boxes remain in closed position; The operating` connections for the air boxes are thus capable of great flexibility of control, all of which is taken advantage of in the conversion of the oven operation into one of theseveral modes of operation. as hereinafter set forth.

Extending along the pusher side of the battery is a producer `gas supply main 46 leading from a suitable source of supply of producer aas and adapted to be opened up to or shut off from its source of supply by means of any improved controlling valve. The valve that controls the supply to the producer gas main 46 is not herein illustrated for reason that the specific construction of such valve is wholly immaterial to the present invention. Leading into each air box of both

series

36 and 37 is a branch supply pipe 47. Connected with the branch pipes 47 that feed the pairs H of air boxes are producer gas supply pipes 48 which are individually connected with the producer gas main 46 by means of vertical pipes 49. The vertical pipes 49 are provided with individual valves 50 for controlling the tlow of producer gas into the branch pipes 447` with which such vertical pipes 49 are connected In accordance with' the invention. two waste gas tunnels ,51 and 52 extend longitudinally of the battery and merge at their discharge ends into a single tunnel 53 which leads to a stack 54. Within each of the

tunnels

51 and 52 is a valve 55 permitting each tunnel to be opened up to or shut oil from communication with the stack 54 as desired.

-Each air box of the series 36 is provided with a port 56 that leads to a channel 57 which opens up into the aforesaid waste gas main 51; similarly each air box of the series 37 is provided with a port 58 leading to a channel 59 which communicates with the waste gas main 52. With this construction the waste gas main 51 is connectedby channels 57 with the series of air boxes that control the exhaust from pusher side regenera-4 tors and the waste gas tunnel 52 is independently connected by a further series of channels With the air boxes that vcontrol the flow from the. coke side regenerators. As none of the pusher side regenerators operates for outflow while the coke sidev regenerators are operating for inflow and vice versa, it is not essential that both of the

waste gas tunnels

51 and 52 be concurrently connected with the stack 54. but only one of said tunnels 5l or 52 need'be so connected, while the other is disconnected from the stack 54. Suc-h connection or disconnection of the

tunnels

51 and 52 with respect to the stack 54 may be readily accomplished by operation of the `valves 55. By the invention, the entire group of inflow operating regcnerators, whether the inflow is on thc pusher or on the coke side of the battery. may be entirely shut off from the stack, with the result that the gaseous medium which flows rfto the inflow operating regenerators is altogether removed from any possible influence of the stack pull. This feature of the invention is of great advantage, particular` when operating with producer gras for fuel, us will be hereinafter more fully explained in 'connection with the. description of the operationof the battery.

The several air boxes of the series "36 are each provided with mushroom valves 60 for opening and closing the ports 56 with respect to the channels' 57 leading to the waste gas tunnel 51: similarly the several air boxes of the series 37 are provided with mushroom valves 61 for opening and closing the ports llt)` 58 with respect to the channels 59 that leadv f to the waste gas tunnel 52.' The mushrooln valves 60 are operated by valve-operating l levers 62 and the mushroom valves 61 by valve operating levers 63. All of t-hevalveoperating levers of the series 62 are controlled and operated by a single cable 64 and similarly allof the valve-operating levers of the series 63 are controlled and operated by a single cable 65. Concurrently, by operation of the two controlling cables 64 and 65. during the reversal period. hereinbefore mentioned. the several regenerators on one side of the longitudinal dividing line L are shu't olli' from communication with the waste gas tunnel.

Extending longitudinally .along theI pusher side of the battery or plant, is a return waste gas or exhaust supply main 66, which is supplied with waste gas or products of combuslli tion discharged into the waste gas tunnel 53. Suitable connections may be provided for leading aportion of the waste gas'from the tunnel 53 into the waste gas supply main 66, said connections being preferably located at or in the vicinity of the stack. It is furthermore preferable to pass the waste gas from the tunnel 53 through a cooler of any approved construction before feeding such gas into the waste gas supply main 66, as the gas in the tunnel 53 is still too hot, in most cases, for being fed back through the supply main 66 and subsequently into the valve control connections leading from said main 66. The supply of waste gas to the main 66 may be opened up or shut olf at will at the point wl'ere the main 66 is connected with the. tunne 53.

The air boxes of both series H and K are,

cable operated valves 69 having valve operating levers 70, as Shown in Figs. 4, and 5. According to the present arrangement, the pairs of valves 69 corresponding to alternate pairs of air boxes o f the series H are opened when their valve operating levers 7 0 are moved in one direction whereas the pairs of valves 69 corresponding to the pairs of air boxes of the intermediate series K are opened only when their valve operating levers 70 are moved in the opposite direction. All of the valve operatingdevers that control the flow in the branches 47 leading into the entire series of air boxes 36 are operated by a single cable 71 and similarly all of the valve operating levers 70 that control the flow into the air boxes of the entire series'37 are` operated by a vsingle cable 72.

The operation of the battery, when using a special generator gas, such as ordinary producer gas, as a fuel is as follows: the return waste gas main 66 is cut` olf from its source of supply of waste gas by va proper operation of the main controllingmalte-OTE` said main; the supply "of coke oven gas to the coke oven gas main 31 is also shut olf;

the result is that both the return waste gas main 66 and the coke oven gas main 31 bear inoperative relations to the oven, in so far as producer gas operation is concerned. A supply of producer gas is however turned on intputhe producer gas main 46, by open- -ing the-mam valve of such producer gas main and the producer gas enters the vertical pipes 49 and passes into the branch pipes 47 to the pairs of air boxes of the series H, from which branches the gas may flow intolthe regenerators 18 that operate to preheat the producer gas before delivering it into the combustion liues. Assuming that the several regenerators of the pusher side group are operating as inflow regenerators and that the several regenerators of 'the coke side group are operating as outfiow heated air and preheated producer gas.

During the period Within which the regenerators and lues on the pusher side of the battery are operating for upflow, the several controlling devices assume relative ositions as follows: the mushroom valves o the entire series 61 are open thus communicably connecting the outflow operating coke side regenerators with the channels 59 leading to the waste gas tunnel 52; on the other hand, the mushroom valves of the entire series are closed to shut oli communication between the air boxes of the series 36 and the channels 57 leading into thewaste gas tunnel 51. l1`he gate valve 55 of the`waste gas tunnel 51 is shut whereas the gate valve 55 of the waste gas tunnel .52 is open; consequently only thoserregenerators andair boxes, in which outflow is bein maintained, are subject to the stack pul, and the regenerators and airt boxes which areoperating for inflow are entirely shut olf from any possible influence of the stack, pull. TIE result is that no air or producer gas which enters theV air boxes of the series 36, operating for inflow, can be drawn past the closed mushroom valves of the series 60 into the stack rand wasted. 'The air box lids 38 ofthe 4side regenerators and flowing outwardly through the air boxes of the series 37 and the open mushroom valves 61 pass into the waste gas tunnel 52 to the stack 54.

On reversal of the battery, the coke side lues and regenerators are operated for inflow whereasl the pusher side flues and regenerators are operated for outflow. During this period of operation, the entire series of air boxes 36 is connected with the waste gastunnel 51 which is communicably connected with the stack 54 by opening its gate valve 55. The waste as tunnel 52 is shut olif from the stack by c osin the valve 55 of sald waste gas tunnel 52. he air boxes 37 of the groupv H are connected with the producer gas main whereas the air boxes 37 of the group K are opened up to the atmospheric air.

In operatin the battery with coke oven gas in the or inary manner, both the producer gas in the main 46 and the waste gas in the main 66 are shut off and at the same time both cables 71 and 72 are operated to positions to close the entire series of valves 69. On reversal of the battery from the pusher side to the coke side and vice versa, both air box

lid controllin cables

42 and 43 are operated simultaneousy in the same direction to open either the ent-ire series of air boxes 86 to the outer air or vice versa to open the .entire series of air boxes 37 to the outer air, Ithis depending on whether the inflow i`s maintained throu h the regenerators on the coke or pusher side of the battery. The cables 64 an 65 are operated in alternation at the end of each reversal to connect either the entire series of air boxes 36 with the waste gas tunnel 51, or the entire series of air boxes 37 with the waste gas tunnel 52. When one of said waste tunnels is in communication with the stack the other is shut off from communication therewith in the manner hereinbefore described. When operating in this manner, all of the regenerators on one side of the battery operate as air regenerators, while all of the regenerators on the other side of the battery operate in the usual way as outflow regenerators. On reversal the outow regenerators become air regenerators and the air re enerators become outflow regenerators. e coke oven gas is turned on into the coke oven gas mam 31 and the supply connections 32 are operated at each reversal period to permit coke oven gas to ilow t the upburning lues and concurrently to cut off the lsupply of coke oven gas from the downow operatin flues.

Whenuburning co e oven gas as fuel, combined with a supply of neutral gaseous diluent to'the u burning ilues, the followingis the mode o operation: the supply of producer gas to the producer as main 46 is turned ot and the supply o coke oven gas to the coke oven gas mam 31 is turned on.

- than the cokin The reversal of coke oven as to the flues on the opposite sides of t e longitudinal dividing line L is effected in the same inauner as in the ordinar coke oven gas operation just described. y operating the main controlling valve of the return waste gas main 66 a supply of cooled waste gas is permitted to ilow from th'e waste gas tunnel 53 into said main 66. When one series of regenerators operate as air regenerators, the regenerators intermediate such air regenerators operate as return waste gas regenerators for supplying neutral gaseous diluent to the ues. This is accomplished by operating the lvalves 69 of alternate inflow operating regenerators in such manner as to connect these regenerators with the return waste gas tunnel 66. The outflow into the stack 54 is controlled in exactly the same manner as hereinabove described. n

If desired, each

waste gas tunnel

51, 52 may be provided with a damper 73, for controllin the outflow to the stack 54, when the va ve is open.

The invention as hereinabove set forth is embodied in a particular form of conStruc tion but may be variously embodied within the scope of the claims hereinafter made.

I claim:

1. In a coke oven battery, in combination: a plurality of horizontally elongated coking chambers arranged side by side;

chambers and respectively constituted of vertical combustion flues; horizontally elongated regenerators located at a lower level chambers and the heating walls and para el therewith, said regenerators being grouped into pairs crosswise of the battery and. communicably connected with combustion flues of said heating walls; a producer gas main located on one side of the battery; reversing valve connections between said main and -alternate pairs of said regenerators; reversing valve connections for connecting the pairs of regenerators that are intermediate such alternate pairs of regenerators 'with'. ythe outer air; a stack; a pair of waste gas tunnels located on the same side of the battery as said producer as main and adapted to be communica ly connected with said stack; valve connections between one of said tunnels and the pusher side regenerators on one side of the oven; valve connections between the other of said tunnels and the coke side regenerators on the opposite side of the oven; and controlling valve mechanism for communicably connecting one of said tunnels with the stack while shutting oil' the other from communication therewith; substantially as sccified.

2. a coke oven battery, in combination: a plurality of horizontally elongated coking chambers 'arranged side by side;

4heating walls4 contiguous to such coking gated pusher and coke side'regenerators on` opposite sides of the oven located at a lower level than the coking chambers and the heating walls and parallel -therewith and communicably connected with combustion iues of said heating walls; a producer gas main located on one side of the battery; reversing valve connections between said main and some 'of said regenerators; reversing valve connections for connecting other regenerators with the outer air; a stack; a pair of waste gas tunnels both. located on the same side of the battery as said main and adapted to be communicably connected with said stack; valve connections between one of said tunnels and the pusher side regenerators on one side of the oven; valve connections between the other of said tunnels and the coke side regenerators on the opposite side of the oven; and controlling valve mechanism connectingone of said tunnelsv with the stack while shutting off the other from communication therewith; substantially as specified. 4

3. In a coke ovenbattery, in combination:

i a plurality of horizontally elongated coking chambers arranged side by side; heating walls contiguous to suchl coking chambers and respectively constituted of vertical combustionfiues; horizontally elongated regenerators located at a lower `.level than the cok ring chambers and the heating Walls and Vparallel therewith, said regenerators being grouped into pairs crosswise of the battery 'andcommunicably connected with combussuch regenerators; reversing valve connections for connecting the pairs of regenerators that are intermediate :such alternate pairs of regenerators with the outer air; a stack; a pair of waste gas tunnels both located on one side of the battery and adapted to be communicably connected with said stack; valve connections between one of said tunnels and the pusher side regenerators on one lside of the oven; valve connections between the other of said tunnels and the coke sfide regenerators on the opposite side of the oven; and controlling valve mechanism for communicably connecting one of said tunnels with the stack while shutting off the other from communication therewith; substantially as specified.

4. In a coking retort oven, in combination: a pluralityy of horizontally elongated coking chambers arranged side byi side; ilued heating Walls contiguous to such coking chambers; horizontally elongated crosswise regenerators for gas and air, operating alternately for inflow and for outflow, said gas and air regenerators being alternately disposed longitudinally of the battery and communicably connected with said flued heating walls; Va produced gas main` communicably connected with all the gas'regenerators; a stack; a pair of waste gas tunnels both located on one side of the battery and adapted to be communicably connected with said stack and with said regenerators; and means for communicably connecting with the stack the waste gas tunnel that is' in communication with the outflow operating regenerators, while shutting off from the stack the waste gas tunnel that connects with the inflow operating re'generators; substantially. as specifled.

5. In a coking retort oven, in combination: a plurality of horizontally elongated coking chambers arranged side by side; lued heating walls contiguous to such coking chambers; horizontally elongated crosswise'` regenerators for gas and air, operating alternately for inflow and for outiiow, said gas and air regenerators being alternately disposed longitudinally of the 'battery and communicably connected with said flucd heating walls; a producer gas main communicably connected with the gas regenerators; a stack; a pair of waste gas tunnels both located on the same side of the battery as -said producer gas main and adapted to be communicably connected with said stack A and with said regenerators; and means for communicably connecting with the stack the waste gas tunnel that is in communication Awith the outflow operating regenerators` while shutting o from the stack the waste gas tunnel that connects with the inflow operating regenerators; substantially as speciied.

JOSEPH BECKER.