Shed for the discharge side of a coke oven battery
United States Patent Nashan et al.  
 (451 Apr. 22, 1975 SHED FOR THE DISCHARGE SIDE OF A COKE OVEN BATTERY Inventors: Gerd Nashau, 24  
 Hirschkampstrasse. 42 Oberhuusen: Jose! Volmari. i6 Heideibeerweg. 463 Bochum; llelmut Peter. 20. Am Hagen. 4619 Oberaden; Gunter Baton. 4. Lanstroper Strasse. 4628 Lunen. all of Germany Filed: Nov. 21. 1973 Appl. No.: 417.818  
 Foreign Application Priority Data Nov. 22. I972 Germany 22$72l4 Dec. 7. I972 Germany 2259889 US. Cl. 202/263; 202/227; 202/262 Int. Cl. ClOb 27/04; Cl0b 35/00 Field at Search 202/227. 228. 229. 230, 202/262. 263  
 [56] References Cited UNITED STATES PATENTS 3.630.852 i2/l97l Nashan et al 202/229 Primary Eramt&#39;ner-Norman Yudkoff Assistant Examiner-D. Sanders Attorney. Agent. or F (rm-Malcolm W. Fraser [57] ABSTRACT A shed for fitment over the discharge side of a coke oven battery has a roof the ridge of which contains a dust and gas extraction system and the roof slopes downwardly from the wall thereof opposite the battery to the wall thereof adjacent the battery. The dust and gas extraction system is connected to a scrubber wherein impurities are removed from the air flow using water from the supply made available for quenching purposes.  
 9 Claims. 2 Drawing Figures mgminmzziszs 3.879.267 samuufg This invention relates to a shed for the discharge side of a coke oven battery. the coke ovens forming at least part of one of the longitudinal walls of the shed and the traction system islocated-at the junction between ti roof and said opposite wall of the shed.  
  The-flow conditions within the shed will thus faci tate removal o&#39;ffthe emissions produced during di charge of cokefrom the ovens and also the removal t fumes which escape around the oven doors if these a shed having an inclined roof. The opposite longitudinal wail of the shed includes supporting pillars and the shed contains a dust and gas extraction system mounted in the roof thereof.  
 A shed of the kind referred to above surrounds the tracks on which the coke trolleys are arranged to run and fits over the oven doors. The use of such sheds enables one to reduce the obnoxious emissions normally associated with coke oven batteries because the dust and gas extraction systems which are at the discharge side of the battery are of high eiiiciency ttnd the sheds can be kept substantially closed.  
  In a known shed of the kind referred to above. the roof slopes downwardly from the side adjacent the coke oven battery towards the opposite side thereof and consequently the ridge of the roof is located imme diately to the rear of the battery. Because the height of the wall opposite the battery must be at least a predetermined amount. a relatively large proportion of the longitudinal wall of the shed adjacent the battery is not formed by the walls of the ovens. This means that the ovens have to support a substantial weight constituted by the weight of this portion of the wall of the shed.  
  The weight which has to be supported is not. however. merely the weight of the shed structure but also the weight of the dust and gas extraction system. Such system has to be arranged at the ridge of the roof since the airborne &#39;dust and gases will tend to gather at the highest part of the shed because of the internal air flow conditions. The known shed design referred to above thus has the disadvantage that the hot gases and airborne dust are forced towards the walls of the ovens and this means. in particular in summer. that the temperature adjacent the top of the battery can be excesstve.  
  in the structure of the known shed referred to above vertical tie bars are employed together with cantilever beams which project at both sides beyond the supporting pillars. This means that a relatively large space (&#39;ltllside the shed is occupied by the shed structure and that the amottnt of constructional material required is considcrable.  
  it has previously been proposed to employ a perforated gas extraction pipe which is arranged in the ridge of a shed roof. which roof is inclined downwardly from the oven battery towards the opposite longitudinal wall of the shed. Such proposal was. however. included in a shed which was heavy and expensive to produce and it is an object of the invention to provide a shed which does not cause excessive loading of the structure of the coke oven battery. is less expensive to produce than known sheds for this purpose and which further is so designed that the internal air flow conditions are such as to avoid excessive temperature increases adjacent the top or the battery.  
  According to the invention there is provided a shed having the features set out above and for fitment over the discharge side of a coke oven battery wherein the roof is inclined upwardly front the side adjacent the battery towards the opposite wall thereof and wherein the ridge ofthc roofwhich contains the dust and gas exnot properly sealed. By arrangement of the dust and g extraction system adjacent the wall remote from ti oven battery. the gas and dust is drawn away from tl ovens and; this means that the electrical equipme which is normally arranged above-the coke receivit trolley on the discharge side of the battery is less a fected by corrosion.- Moreover. because the weight the extraction system is immediately adjacent the su porting pillars of said opposite wall of the shed. the ro loading is reduced. the roof being of cantilever desi; and further the load transmitted to the roof of the ow battery is also reduced.  
  Tie bars for supporting the roof and the wall of t shed spaced from the battery are preferably provid which are inclined downwardly from the roof ridge. ti arrangement providing considerable economies in th it avoids the use of roof beam sections which overha the supporting pillars of said wall. it also provides f a reduction in the total weight of the shed structure in order to regulate the supply of air to the interi of the shed. the wall of the shed spaced from the b: tery can be provided with adjustable flaps. Openings the side walls of the shed through which coke wago pass into and out of the shed are preferably automa caily opened and closed. This arrangement enables o to control air flow conditions within the shed and pt mits dissipation of the hot gases and vapours to ti wail of the shed away from the battery.  
  The invention enables one to reduce the height those parts of the shed other than the longitudinal w spaced from the shed and the roof and that part of t shed wall adjacent the battery not formed by the wt of the ovens may be supported through roller bearit on the roof of the coke oven battery. These roller be ings may be spring&#39;loaded and it has been found t this form of resilient sttpport does not adversely aft the structure of the coke oven battery.  
  in an alternative arrangement. the roof of the shet designed so that it is solely supported by the wall of shed remote from the battery. The shed can be a sl structure with a sheet ntetal lining. Alternatively it n be of reinforced structure with a lightweight conct lining.  
  The dust-and gas-laden .air which is drawn from shed must. of course. be cleaned before it is releaset the atmosphere. Centrifugal separaters and filters c taining fabric materials are known bttt these have permitted removal of the smoke and tar fractions wi the air has contained. Attempts have therefore b made to remove these materials by spraying water the air before the air passes through a series of fan blowers.  
  A large scale trial in respect of the above proved successful and it was found that deposits tendet form on the rotating parts of the fans or blowers c ing these to become unbalanced. Another attcmp precipitate the emitted dust and gases in a eyclont stalled after the fan or blower produced a numbe problems which were concerned primarily with high solids contents of the residues. the solids cau blockage of the flow lines. Thus. in accordance \vi further feature of the invention. improved means are provided for removing the dust..smoke and condensable constituents from the air drawn out of the shed. A part of the water employed to quench the coke is diverted and is used to wash the dust-and gas-laden air extracted from the shed. the air being washed beforeentry thereof into the blowers.  
  By use of a portion ofthe water employed toquench the coke as a washing agent for the dust-and gas-laden air. the washing water containing the impurities can be cleaned in existing filter plants and can therefore be circulated continuously. The amount of water required for quenching purposes is considerably greater than that required to remove the impurities from the air flow and thus no additional pumps need be installed and the quenching water circuit is readily extendable.  
  The residues removed from the scrubbing water will consist mainly of coke particles which can be delivered into the coke quenching water settling tank since these are identical with the coke slag. Unexpectedly. it has been found that. by using a scrubbing process as set out above. tar vapour impurities are readily removed because the tar is absorbed by the coke particles and is removed together with the coke particles. The problems previously encountered concerning the formation of deposits upon the rotating parts of the blowers are thus avoided. During the scrubbing operation the dustand gas-laden air drawn from the shed can be caused to flow in counter-flow relation with the scrubbing water. the air being allowed to flow upwardly and the water being sprayed downward through it.  
  In an alternative arrangement. the dust-and gas-laden air is caused to flow in the same direction as that portion of the coke quenching water which is diverted for scrubbing purposes. this water being atomised so as to saturate the air-stream at the commencement of scrubbin g whereas. at the end of the scrubbing operation. the water is introduced as larger drops to precipitate coarse impurities in the air.  
  It is preferred that the scrubbing process described above be carried out in a spray scrubber which does not include baffle plates. Relatively high air velocities and high spray densities can be obtained and this ensures not only effective dust removal but also effective removal of the tar vapour in the air-stream. Blockages in the scrubbing system are avoided and the low pressure drop in such a scrubber has a favourable effect on the power consumption of the fans or blowers of the dust and gas extraction system.  
  The treatment plant may include a vertical scrubber situated in the extraction line before the fans or blowers of the dust and gas extraction system. the vertical scrubber having a connection at its upper end for the introductionof the dust-and gas-laden air with a series of nozzles at different levels within the scrubber. the nozzles at the higher level or levels being so designed that the water issuing therefrom it atomised whereas the nozzles at the lower level or levels are such as to form droplets of the coke quenching water. the scrubber being provided at its lower end with a discharge outlet for the passage of the scrubbed air to a cyclone the lower end of which is provided with means for carrying out a rinsing operation using the scrubbing water collected in the scrubber.  
  The invention will now be described by way ofexampic with reference to the accompanying drawings wherein:  
  4 FIG. 1 is a diagrammatic cross-sectional view of a coke oven battery and a shed designed to cover the discharge side of the battery and.  
  HO. 2 is a schematic viewof acoke oven battery. shed and extraction equipment? The battery of coke ovens l hasa top 2 over which the usual charging truck 3 canbe. traversed longitudinally of the battery. The usual clearingtruck is movable along the front 4 of the battery although this has not been showmAt the opposite side 5. normally referred to as the discharge side. a coke delivery trolley 7 runs on rails 6. the trolley being operated through trolley wires 8. The discharge side 5 of the battery of ovens is covered by a shed structure 9.  
  One of the longitudinal walls of the shed structure is partially formed by those walls l0&#39;of the ovens which face towards the discharge side. A small part of this longitudinal wall of the shed is marked it and consists of dependant rods 12 to which a lining i3 is attached. the lining being made up of sheet metal or light concrete sections. The shed roof 14 is inclined. lts beams rest upon vertical pillars l5 and obliquely extending tie bars 16 are provided which terminate at foundations l7. Stiffeners l8 link the tie bars l6 and the pillars 15.  
  The roof ridge [9. i.e. the highest point 19 of the roof which slopes downwardly towards the coke ovens l. is at the junction between the roof and that longitudinal wall 20 of the shed which is disposed opposite the oven walls. The longitudinal wall 20 of the shed. like the roof l4. consists of sheet metal liners or lightweight concrete liners supported on the pillars i5 and the roof beams.  
  At the ridge [9. there is a dust and gas extraction systern including a pipe 21. The fans and the dustseparation equipment associated with this pipe 21 have not been shown. The tie bars 16 terminate at the ridge l9 of the shed.  
  To regulate the air supply to the shed. that longitudinal wall 20 of the shed which is located opposite the ovens walls 10 is provided adjacent a coke ramp 26 with an adjustable flap. Also. the transit openings for the coke delivery trolleys 7 are equipped with automatically opening and closing doors. Other flaps 23 regulate openings 24 which are provided adjacent the ridge 19 of the shed. i.e. near the top of the longitudinal wall 20. The air supply to the shed is controlled by means of the flaps 22 and 23. which can be connected together through a linkage 28. A catwalk 25 is suspended from the pillars l5 and enables operators to observe not only the flaps 22 and 23 but also associated openings of lighting systems arranged in the top part of the shed. as well as the equipment housed in the shed. this including coke discharge wagons 27.  
  The coke oven battery has been marked 20! in FIG. 2. its discharge side 203 being covered by a shed structure 204. The shed has vertical pillars 205 set in foundations 206. and a roof 207 inclined downwardly towards the coke ovens 201. When the coke oven doors are opened. a convection flow is obtained in a direction towards the higher parts of the shed structure 204 and a dust and gas extraction system 209 is located substantially at the ridge of the shed 204.  
  Of this device. in the drawing. only. a collecting line 210 has been shown and this is provided at spaced intervals with inlet connections 21 1. During discharge of the coke from an oven into the coke wagons 212. there is a considerable emission of dust and obnoxious gases.  
 This emission passes into the collection space at the top of the shed and is drawn upwards into the line M and fed to a scrubber 213. The scrubber has a connection 214 at its upper end for the line 2l0 and. within the scrubber. a plurality of nozzles 215 and 216 are arranged in groups at two different levels.  
  Both groups of nozzles receive scrubbing water from a line 217. which water is drawn from a quenching water vessel 218. The quenching water vessel 218 forms part of a coke-quenching tower 219 in which the quenching water is sprayed downon to wagons 212 holding the glowing coke. The spent quenching water collects in a settling tank 220 from which it is extracted by means of a pump 22! and recycled through a line 222 to the vessel 8.  
  A sump 223 is used to collect the solids which are drawn oil by means of a pump 224 through a line 225 into a coke breeze bunker 226. As can be seen. the quenching water circuit is a closed circuit. and thus it is only the losses occurring during the quenching operation which have to be made good by the addition of further water.  
  The top group of nozzles 2 l5 atomise the water delivered therefrom so that the air introduced into the scrubber 213 at 214 is saturated. The group of nozzles 216 arranged at the lower level. produce larger droplets at a relatively high density. Thus. smoke particles. tar vapour and larger dust particles are precipitated. The descending water droplets collect in a sump 230 at the bottom of the scrubber 213. The scrubbed air is drawn oft at BI and fed into a cyclone 232 which is connected to one or more blowers 233 which deliver the air to the atmosphere at 234. The scrubbing water is drawn from the sump 230 and fed through a line 235 to the bottom part 236 of the cyclone 232. and thence together with the residues from the cyclone through a line 237 into the settling tank 220. Here. the solids. mainly coke particles. pass into the sump 223 by sedimentation. The dust-and gas-laden air passes downwards through the scrubber 213. As a result. high gas velocities and a multi-stage water jet system. can be used.  
 We claim:  
  I. A shed structure for covering the discharge side of a coke oven battery. comprising an upright wall spaced laterally from the coke oven battery and forming with the side of the oven battery an enclosure. a roof inclining upwardly and outwardly from the top of the oven battery to said upright wall. a dust and gas extraction system located within the shed structure at the ridge or junction between said roof and said upright wall. said upright wall including vertical reinforcing pillars extending throughout the height of the wall and upon which said roof rests. and tie bars supporting said roo and wall inclining downwardly and away from sail ridge.  
  2. A shed structure as claimed in claim I. comprisin a relatively short wall portion of the shed constitutin substantially an upward continuation of the adjacen oven battery and to which the lower end of the incline roof is fixed. I  
  3. A shed structure as claimed in claim I. comprisin flaps for regulating the air supply to the shed. said flap including flaps at the lower portions of said upright wa and flaps at the upper portions of said wall. and linkag connecting said upper and lower flaps for actuatin same.  
  4. A shed according to claim 2. wherein the roof an that part of the longitudinal wall of the shed not consti tuted by the walls of the ovens on that side of the she adjacent the ovens is supported by roller bearings upo the roof of the coke oven battery.  
  5. A shed according to claim 4. wherein the rolle bearings are spring-loaded.  
  6. A method of operating a shed for a coke oven bai tery which includes a dust and gas extraction system lc cated adjacent the ridge of the root of the shed. sai method being characterised in that the dust-and gas laden air extracted from the shed is scrubbed wit water before passing to blowers forming part of said ct traction system. this water being part of the supply use for coke-quenching purposes.  
  7. A method according to claim 6. wherein the wate used to scrub the dust-and gas-laden air is thereafte fed to a settling tank of the quenching system.  
  8. A method according to claim 6. wherein the dus and gas-laden air flows in the same direction as th water used for scrubbing purposes and wherein th scrubbing water is introduced as a first portion whic is atomised to saturate the air and a second portio which is in the form of droplets and serves to precip tate solid impurities.  
  9. Apparatus for use in the removal of impuritii from the dust and gas extraction system of a shed ft a coke oven battery. said apparatus including a vertic scrubber which has a connection at its upper end it the introduction of dust-and gad-laden air and is pr vided with nozzles at a first level through which at mised water is introduced with further nozzles at lower level which form droplets of water. the scrubb being provided with an outlet at its lower end and ti outlet being connected to a cyclone which includ means for carrying out a rinsing operation on the scru bed air using the scrubbing water collected in t1 scrubber.  
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