DE19510993C1 - Device for thermal exhaust gas treatment, in particular of oxidizable carbonization gases - Google Patents

Abstract

The invention concerns a device for the thermal waste gas treatment, in particular of oxidizable low-temperature carbonization gases, the device comprising a first reactor (4) with a heat-accumulator body (A), a heating zone (6) and a second reactor (5) with a heat accumulator (B). Waste gas is alternately fed to and removed from the reactors arranged in series. The reactors (4, 5) are disposed in an elongate horizontal situation with heating zones arranged therebetween. The ends (11, 12) of the reactors are provided with inlets and outlets (13, 14, 15, 16) with controllable flaps (20, 21, 22, 23) for the waste gas.

Description

The invention relates to a device for thermal exhaust gas treatment, in particular of oxidizable carbonization gases, with the Features of the preamble of claim 1.

EP 0 472 605 B1 describes a system and a method for thermal exhaust gas treatment known in which the reactors as vertical towers are arranged. There will be at least two Reactor towers used. The entry and exit of the exhaust gases is provided at the bottom of the reactor towers. The top ends of the Reactor towers are connected via a deflection housing. There there is also a combustion chamber with burners. The reactor towers are filled with ceramic bodies. The one with organic Raw gas laden with pollutants enters a reactor tower and is when flowing through the hot heat storage body heated. In the heating chamber, the raw gas is burned ners, e.g. B. natural gas burner, for the afterburning of the organic harmful gases heated temperature necessary. The heated, cleaned exhaust gas is drawn to the second reactor tower directs and releases them from the store in the first tower heat taken up and added in the deflection channel is as complete as possible dig in the second tower to the storage again. The cooled down Clean gas, which is only one when exiting the second reactor tower has a little higher temperature than the raw gas when entering the first reactor tower, is then over the chimney derived.

The gas flows are at regular intervals, e.g. B. from approx. two to three minutes, switched. The second takes over Reactor tower now the function of heating the raw gas, while the storage in the first reactor tower the heat of the hot Clean gas.  

The construction of reactor towers is for static reasons complex. The introduction of the storage trimmings into the reactor towers is cumbersome. In addition, the guidance of the exhaust gases is like it is also difficult to remove deposits.

It is also be in such systems knows to use a single reactor tower in which the two reactors arranged one behind the other with intermediate the switched combustion chamber in an extended position. Also the disadvantage here is that for statics reasons an expense ger construction is required. The individual trimmings are also to intercept the reactors with appropriate support grids, which again for complex static and thermal reasons must be built.

The invention has for its object a device for to create thermal exhaust gas treatment that is easier Design with simplified statics possible. In addition, should the insertion and removal of the memory in the device be relieved. The removal of deposits and that Leading the exhaust gas flows in the device should improve who the.

The invention solves this problem with the Merk paint of claim 1.

The stretched, lying device for thermal exhaust gas deal with reactors with combustion chamber in between simplifies the statics and thus the construction of the reactor ren. There is thus the possibility with reasonable techni higher storage masses to let. This can come up as soon as the temperature rises fluctuation of the exhaust gases to be cleaned or alternating Pollutant concentration must be managed.  

As a result, longer switching cycles between gas up can occur heating and cooling can be selected without the afterburning process is adversely affected. This results in how the lower the amount of unpurified gas coming from the dead space volume during the switching process result. So it will only a small proportion of unpurified exhaust gas animals. As a side effect, there is a lower mechanical load stung, z. B. Wear of the movable parts of the switching flap pen a.

The possible higher storage mass also requires a higher one free flow area. This will make a lower one Cross-sectional load of the device reached. Especially with higher dust and soot loading of the exhaust gas to be cleaned the danger of the free cross-sections increasing in the front direction practically excluded. Associated with this is a lower total pressure loss of the device. this means a lower expenditure of electrical energy for operation of the exhaust fan.

Finally, there is also an extension to be carried out subsequently tion of the device easily possible. The Vorrich device in modular design. When extending the pre direction, one or more modules can then be added.

The stretched, lying arrangement also improves the guidance of the exhaust gas. So the pressure loss due to the omission of an order steering channel reduced.

According to one embodiment of the invention, the reactors are included Heating chamber designed to rest on the floor.

If there is no space, it is also possible to have one Attach device above other overall system parts.  

According to another embodiment of the invention, everyone is heat storage made of refractory bricks with slots between in Longitudinal successive rows of stones built. Through the setting slots, the mixing of the Exhaust gases. Auxiliary burners and / or circulation are in the setting slots fans can be used.

Preferably, chamotte multi-hole Stones use.

According to a further embodiment of the invention, the stones each heat accumulator to its longitudinal direction with the Lochkanä len arranged obliquely, the oblique channels in the lower half against the channels in the upper half run. As a result, in the subsequent open spaces, e.g. B. combustion chamber or hood-like ends, an improved Mixing of the exhaust gases achieved.

According to a further embodiment of the invention, as Stones Solid stones for transverse tapes in the heat store be used.

The stones are preferably arranged as double impacts successive distances to form the setting slots point.

According to a further embodiment of the invention Ceiling and / or the side walls of the heating chamber opposite de, in terms of height offset burner provided. Here through a circulation of the exhaust gases in the heating chamber he enough.

To be able to easily walk through the heating chamber, e.g. B. Deposit remove one side of the heating chamber with a Provide door over which a burner is arranged.  

According to a further embodiment of the invention, the outside jacket of the system is formed by a housing at each end a collecting hood with connections for incoming and outgoing connections has connections for the exhaust gas and sockets with control flaps for the alternating lines.

Any collector hood that is tubular with rectangular or round Cross-section is formed, can have a flat end face zen, which is designed as a lifting gate. You can use this lift gate the storage inventory of each reactor, e.g. B. by a forklift be retracted and extended. The memory stocks can in terms of their structure, size and composition to changed conditions, e.g. B. modified exhaust gas values written limit values and the like.

The outer housing is preferably inside and / or outside heat isolated.

In order to also remove deposits from the heat stores in the setting slots in the middle near the bottom led, lockable pipe socket available. Make this possible the introduction of a suction hose for vacuuming the Deposits.

To improve the heating of the heat storage can Ends instead of stones tube stack made of good heat-conducting material, e.g. B. copper.

The insertion slots of the heat accumulator can be used to store heat the pourable material. This will Heat storage value increased.

Further refinements of the invention result from the other subclaims.

The invention is described below with reference to a drawing illustrated embodiment explained in more detail. In the Show drawing

Fig. 1 is a schematic representation of the top view of the device according to the invention,

Fig. 2 is a cross section along the line II-II in Fig. 1,

Fig. 3 is a partial end view of a heat accumulator,

Fig. 4 is a partial plan view of the heat accumulator, and

Fig. 5 and Fig. 6 views as in Fig. 1 and 2 a changed embodiment.

The raw gas to be burned is fed via a raw gas line 1 to the device for thermal exhaust gas treatment 2 . The device 2 has an outer housing 3 made of internally and / or externally insulated metal.

The outer housing 3 can be assembled in the longitudinal direction from divided modules in a manner not shown.

The outer housing preferably has a fire for insulation most inner lining, e.g. B. from chamotte, ceramic fibers or similar. The steel outside of the housing can also be insulated in a similar way. It should be noted that the occurring temperature does not fall below the dew point.

In the housing 3 reactors 4 , 5 are in a lying position with inter mediate heating chamber 6 , preferably one, angeord net. The device 2 preferably rests on the floor 10 . Due to the horizontal arrangement, the statics and construction are considerably simplified.

The ends 11 , 12 of the outer housing 3 of the device 2 are hood-shaped. They have connecting pieces 13 , 14 , 15 , 16 . In these controllable flaps 20 , 21 , 22 , 23 are arranged.

The opposing connecting pieces 14 , 16 are connected via an external pipeline 25 . Likewise, the connecting pieces 13 and 15 are connected to one another via an external pipeline 26 .

The pipes 25 , 26 are depending on the position of the Klap pen 20-23 in one way or another through the exhaust gas through-flow.

The hoods 27 , 28 at the ends 11 , 12 have drivable doors 30 , 31 . The spaces of the ends 11 , 12 delimited by the hoods 27 , 28 can be cleaned of exhaust gas residues via them. In addition, the components of the heat accumulator 35 can be introduced into the outer housing 3 .

The heat accumulator 35 is divided into two groups A, B. Each of the groups A, B is formed by a trimming body 38 . This preferably consists of chamotte multi-hole stones 39 .

The trimming body 38 is preferably formed by rows of stones 45 running at an angle to one another. The stone rows 45 are separated from one another by slots or spaces that form oblique channels 45 a. The arranged in the upper half chamotte multi-hole stones 39 are opposite to the arranged in the lower half stones 39 opposite duri fend. This results in a better swirl effect (mixing).

A band 47 of multi-hole stones is preferably provided in height in the middle. The detailed trimming of the fireclay multihole bricks 39 is shown in Fig. 3 and Fig. 4 ersicht Lich. All stones 39 are of the same design. They have a large number of perforations 48 transverse to their longitudinal direction.

The upper layer 49 and the lower layer 50 are formed by stones 39 which adjoin one another laterally and at the front without a large distance from one another. The longitudinal axes of the stone rows are opposite to each other and oblique to the flow direction 55 .

The stones 39 of the middle layer 47 are arranged perpendicular to the flow direction 55 of the exhaust gas. The stones 39 are arranged abutting one another at the end face. In the flow direction 55 of the exhaust gas, they are spaced 45 b apart.

The trimming body 38 , which is formed by the chamotte multi-hole bricks 39 , has transverse slits 36 running transversely to the flow direction 55 . This creates transverse body discs 37 . These are preferably constructed from the multi-hole stones 37 . A number of solid stones can also be distributed in these facing body disks 37 . This creates an additional deflection and thus better mixing of the exhaust gas.

The trimming body discs 37 are generally constructed as double impacts, which are at a distance from one another to form the setting slots 36 . The slits 36 achieve a certain calming of the exhaust gas flow and a temperature equalization.

Additional auxiliary burners can be arranged in the slits 36 as ceiling and / or side burners. As a result, the circulation of the exhaust gases in the setting slots 36 is improved. In addition, a temperature equalization in the reactor 4 or 5 is achieved. Temperature fluctuations are also smoothed out.

Between the two heat storage groups A, B, the heating chamber 6 is arranged in a row and in an extended position. As can be seen from Fig. 2, the outer housing 3 preferably has a substantially rectangular cross-section, preferably quadratic cross-section. Two burners 40 , 41 are preferably arranged as main burners in this heating chamber 6 . Side burners can also be used. These are arranged at different heights in order to circulate the exhaust gases in the heating chamber 6 . So z. B. the burner 40 near the top of the chamber 6 angeord net, while the burner 41 on the opposite side wall of the outer housing 3 is arranged near the bottom 10 .

This also facilitates the attachment of a door 42 . Via this, any deposits in the heating chamber 6 can be cleared. In addition, the insertion of the trimmings for the heat storage groups A, B can be made possible.

The combustion chamber 6 as well as the slits 36 can be provided shortly above the floor 10 with outwardly leading, closable Rohrstut zen, the introduction of a suction hose and the removal of any deposits even during operation.

It can be used with extreme requirements, such as large fluctuations in raw gas quantities and pollutant concentrations, Umwälzventila gates, which are arranged both in one and in several setting slots 36 and rotate in one direction or can be switched in the opposite direction.

In special cases, e.g. B. if there is not enough space, it is possible to use short metal pipes, preferably copper pipes, at the two ends 11 , 12 under the hoods 27 , 28 instead of chamotte multi-hole bricks 34 , as a result of which a significantly faster heat transfer can be achieved and the dimensions of the two heat storage groups A and B can be shortened.

It is also possible to replace the metal parts, preferably copper pipes, with hanging metal chains. The close-fitting chains allow easy cleaning of deposits that have deposited on them. By simply shaking the chains, e.g. B. manually or by an automatic device, the anla gerenden residues on the chain parts, z. B. dust or soot can be removed. Before preferably these chains are arranged in the area of the ends 11 , 12 under the hoods 27 , 28 .

The operation of the device 2 is explained in connection with FIG. 2. The controllable flaps 20 , 21 , 22 and 23 are in the positions shown. Then flows the nachver burning, cool raw gas via lines 1 and 26 to the connection spigot, is fed to the reactor 5 and absorbs heat from the trimming body 38 . The exhaust gas is then further heated in the heating chamber 6 . The further flowing exhaust gas then heats the filler body 38 of the regenerator 4 which had previously cooled in the previous operating phase to the optimum temperature (e.g. 800 ° -900 ° C.). The exhaust gas then flows out via the free connection piece, the pipeline 25 , the pipeline 60 , the blower 61 , via the chimney 62 .

When after a while - e.g. B. several minutes - subsequent operating phase, the exhaust gas is fed via line 1 to the reactor 4 with reversed flap 20 . Since the other flaps 21 , 22 and 23 are in their reverse flap position, the exhaust gas flows through the heating chamber 6 to the reactor 5 and further via the connecting piece 16 to the fan 61 , such as the chimney 62 . The operating phases are then repeated.

Due to the selected structure and arrangement of the stores, the device 2 also has optimal mixing and reaction zones. The exhaust gas to be cleaned is always mixed again before it enters the next fill.

Depending on the type and concentration of pollutants, it begins in partial oxidation in the middle part of one reactor the hot contact surfaces flowing around. These reactions  plant within steadily increasing oxidation rates within of the storage population.

At the end of each reactor is then the required Combustion temperatures around 800 ° C the pollutant combustion already finished. The cleaned exhaust gas, which is a big one Contact area had to flow through, is then in the respective following zone for the purpose of delivering energy to the trimming elements sent.

The temperature resistance of the thermal reactor at which there are no metallic materials in the high temperature range, The standard version is approx. 900 ° C and can be used for Special cases can still be increased. A special The advantage of the device lies in its ability to handle the primary thermal efficiency by varying the stock storage too change.

Thanks to the modular design, it is possible to change the product tion conditions, e.g. B. reducing or increasing pollutants, adjust the necessary primary energy requirements immediately.

The device can also be operated on a catalytic basis will.

According to the embodiment of FIGS . 5 and 6, it is also possible to replace the heating chamber 6 by one or more trimming bodies 38 with slits 36 . In this case, the entire arrangement can be understood as consisting of a single reactor body, which preferably has setting slots 36 . In the setting slots 36 , preferably a plurality of trimming bodies 38 , burners, preferably one or more tubular high-speed burners 70 are to be provided over a heating zone. In this case, the burners could only be operated partially if flammable components are present in the exhaust gas. The desired combustion temperature is regulated by switching it on and off or by controlling the burner output. If the pollutant content in the raw gas exceeds the amount required for autothermal operation, a partial volume flow of the hot exhaust gas is decoupled directly from the heating chamber or heating zone.

The result is a device 2 with continuous, preferably the same facing bodies 38 . The length of the heating zone can be changed accordingly by switching the burner 70 on or off. There is also the advantage of faster heating of the heating zone. The entire trim body can be formed uniformly. The high speed burners 70 used are cheaper and more effective.

Finally, each end 11 , 12 can also be formed with a tubular longitudinal part and a flat end part instead of in the form of hoods. The tubular end part then has the connection piece. The flat end part can then be formed as a lifting gate. About such a lift gate, the renewable heat storage stock, z. B. by a forklift, drive out or in. The storage stock to be retracted can be prepared outside the device 2 , with regard to its length, its cross section and its composition, adapted to changing conditions, such as, for. B. exhaust gas composition, limit values, etc. be prepared.

With heavier trimmings with greater heat storage capacity the switching periods are extended.

Claims (24)

1. Device for thermal exhaust gas treatment, in particular of oxidizable carbonization gases, with a first reactor ( 4 ) with heat storage body A, a heating zone ( 6 ) and a second reactor ( 5 ) with heat storage B, exhaust gas being alternately fed and removed to the row arrangement of the reactors , characterized in that the reactors ( 4 , 5 ) with the heating zone ( 6 ) in between are arranged in an extended, lying position. 2. Device according to claim 1, characterized in that the reactors ( 4 , 5 ) with heating zone ( 6 ) on the bottom ( 10 ) are formed lying. 3. Apparatus according to claim 1, characterized in that each reactor ( 4 , 5 ) with a heat accumulator (A, B) is constructed from fire-tested stones ( 39 ) and setting slots ( 36 ) between the stones ( 39 ) follow one another in the longitudinal direction de Form heat storage discs ( 37 ). 4. The device according to claim 3, characterized in that auxiliary burners can be used in the setting slots ( 36 ). 5. Apparatus according to claim 3, characterized in that chamotte multi-hole stones ( 39 ) are used for each heat storage group (A, B). 6. Apparatus according to claim 3, 4 or 5, characterized in that the stones ( 39 ) of each heat storage group (A, B) form obliquely extending channels ( 45 a) to its longitudinal direction, the oblique channels in the lower half ( 50 ) ent against the channels in the upper half ( 49 ) and that a middle layer ( 47 ) with stones ( 39 ) is present, which have distances ( 45 b) in the flow direction ( 55 ) of the exhaust gas. 7. Device according to claims 3 to 6, characterized in that solid bricks in the transverse heat storage discs ( 37 ) are stored. 8. Device according to claims 3 to 7, characterized in that the stones ( 39 ) are arranged as double joints and between the double joints insertion slots ( 36 ) are present. 9. The device according to claim 1, characterized in that the heating zone is a heating chamber ( 6 ) and the side walls of the heating chamber ( 6 ) opposite, offset in height arranged burner ( 40 , 41 ). 10. The device according to claim 9, characterized in that the one side wall of the heating chamber ( 6 ) has a door ( 42 ). 11. The device according to claim 1, characterized in that each end ( 11 , 12 ) of the outer housing ( 3 ) is surrounded by a hood ( 27 , 28 ), with doors ( 30 , 31 ) and connections ( 13 , 14 , 15 and 16 ) for the exhaust gas and that nozzles with controllable flaps ( 20 , 21 , 22 , 23 ) are provided for the alternating lines ( 25 , 26 ). 12. The apparatus according to claim 1, characterized in that in the setting slots ( 36 ) in the middle near the bottom end closable pipe socket into which a suction device can be inserted. 13. The apparatus according to claim 1, characterized in that circulation fans can be used in the setting slots ( 36 ). 14. Device according to claims 1 to 13, characterized in that at the ends ( 11 , 12 ) of the reactors ( 4 , 5 ) instead of stones ( 39 ) parts of good heat-conducting material are arranged. 15. The apparatus according to claim 14, characterized in that the parts are stacked pipes made of heat-conducting material are. 16. The device according to claims 1 to 13, characterized indicates that the parts are made of a highly conductive material tightly hanging chains. 17. The apparatus according to claim 16, characterized in that the tightly hanging chains with a jogger tion are connected. 18. Device according to claims 1 to 17, characterized in that the setting slots ( 36 ) are filled with heat-storing, free-flowing material. 19. Device according to claims 1 to 18, characterized in that an outer housing ( 3 ) is present, which is insulated inside and / or outside. 20. The apparatus according to claim 1 and 4, characterized in that the heating zone ( 6 ) by one or more trimming discs ( 37 ) is formed with setting slots ( 36 ) and preferably one or more tubular high-speed burners is / are arranged in each setting slot. 21. The apparatus according to claim 11, characterized in that each end ( 11 , 12 ) of the outer housing ( 3 ) is formed by a hood with a longitudinal tube part and a flat end part, the end part being designed as a lifting gate. 22. The apparatus according to claim 17, characterized in that the outer housing ( 3 ) is built up in the longitudinal direction from module parts. 23. The device according to claim 22, characterized in that each housing module part prepares part of a heat has storage body (A, B). 24. Device according to one of the preceding claims, characterized in that gas is coupled out of the heating zone ( 6 ) when a predetermined temperature is exceeded.