CN214840804U - Device for reducing NOx emission through flue gas recirculation - Google Patents

Abstract

The utility model relates to a device that flue gas recirculation reduces NOx and discharges relates to the field of flame heating furnace, and it includes radiation chamber and convection chamber, the radiation chamber has the combustor, convection chamber and radiation chamber communicate mutually, still includes the flue gas circulation subassembly, the flue gas circulation subassembly includes smoking pipe, circulating fan, send cigarette house steward and a plurality of cigarette branch pipe that send, the exit of radiation chamber is located to the one end of smoking pipe and communicates mutually with the radiation chamber, circulating fan's air intake and the other end intercommunication of smoking pipe, send the air outlet intercommunication of cigarette house steward and circulating fan, a plurality of send the cigarette branch pipe all with send the cigarette house steward to communicate mutually, send the cigarette branch pipe to keep away from the one end and the combustor intercommunication that send the cigarette house steward. The problem of a large amount of NOx that have improved easy production in the combustion process directly discharge from the induced-draft fan, cause environmental pollution is solved, this application has simple structure, does not influence flame heating furnace thermal efficiency, does not change the effect of radiation chamber and convection current room heat distribution ratio.

Description

Device for reducing NOx emission through flue gas recirculation

Technical Field

The application relates to the field of flame heating furnaces, in particular to a device for reducing NOx emission through flue gas recirculation.

Background

At present, the domestic flame heating furnace generally adopts a steam spray gun technology that a low NOx burner is matched with a bottom burner, the temperature of the flame center of the bottom burner is reduced by reducing the injection of steam, and then the generation of thermal NOx is inhibited, so that the standard emission of NOx under the working conditions of normal operation, coke burning, heat standby and the like of the heating furnace is realized.

In the related art, referring to fig. 8, a flame heating furnace includes a radiation chamber 1 and a convection chamber 2, and a burner 11 is installed in the radiation chamber 1 to perform heating. Install the radiation boiler tube in the radiation chamber 1, convection chamber 2 and radiation chamber 1 intercommunication each other, draught fan 21 is installed to the upside of convection chamber 2 for radiation chamber 1 flows to and receives the effect that draught fan 21 discharges from the upside of convection chamber 2 to the flue gas in convection chamber 2.

In view of the above-mentioned related arts, the inventors believe that a large amount of NOx is easily generated during the combustion process, and is directly discharged from the induced draft fan, causing environmental pollution, and there is room for improvement.

SUMMERY OF THE UTILITY MODEL

In order to improve and produce a large amount of NOx easily in the combustion process, directly discharge from the induced air machine, cause environmental pollution's problem, this application provides a flue gas recirculation reduces NOx and discharges device.

The application provides a device that flue gas recirculation reduces NOx and discharges adopts following technical scheme:

the utility model provides a device that flue gas recirculation reduces NOx and discharges, includes radiation chamber, exhaust connecting pipe and convection chamber, the radiation chamber has the combustor, convection chamber and radiation chamber communicate each other, still includes the flue gas circulation subassembly, the flue gas circulation subassembly includes smoking pipe, circulating fan, send the cigarette house steward and a plurality of branch pipes that send the cigarette, the exit of radiation chamber is located to the one end of smoking pipe and communicates each other with the radiation chamber, circulating fan's air intake and the other end intercommunication of smoking pipe, send the air outlet intercommunication of cigarette house steward and circulating fan, it is a plurality of send the cigarette branch pipe all communicate each other with sending the cigarette house steward, send the one end that the cigarette house steward was kept away from to the branch pipe and communicate with the combustor.

By adopting the technical scheme, the high-temperature flue gas with very low oxygen content is mixed with fresh air through the flue gas recirculation system, and the oxygen content of the mixed combustion air is reduced, so that the combustion intensity and flame temperature of the radiation chamber can be reduced, and the NOx generated by combustion is obviously reduced. Meanwhile, because the high-temperature flue gas sucked out from the outlet of the radiation chamber returns to the radiation chamber, the heat is not lost, and the flue gas amount entering the convection chamber is the same as the amount when the flue gas recirculation system is not added, the heat distribution ratio of the radiation chamber and the convection chamber cannot be changed, and the heat efficiency of the flame heating furnace cannot be reduced.

Optionally, the smoking pipe is provided with a first air suction pipe, and the first air suction pipe is communicated with the smoking pipe.

By adopting the technical scheme, the arrangement of the first air suction pipe mixes the high-temperature flue gas which is just sucked out with the fresh air, so that the temperature of the flue gas in the smoke suction pipe is reduced, the pipeline in the subsequent flue gas circulation component does not need higher material grade, the manufacturing cost of the subsequent pipeline is reduced, and the production cost is reduced.

Optionally, a second air suction pipe is arranged on the smoke delivery main pipe, and the second air suction pipe is communicated with the smoke suction pipe.

By adopting the technical scheme, the second air suction pipe is arranged on the smoke delivery main pipe, so that the circulating fan only needs to convey smoke in the smoke delivery main pipe, air and smoke entering the smoke delivery main pipe can be sucked into the radiation chamber by virtue of negative pressure of the hearth to participate in combustion, the power of the circulating fan is reduced, the production cost is saved, and the manufacturing cost of the whole smoke circulation assembly can be reduced by being matched with the first air suction pipe for comprehensive use.

Optionally, a first external thread is arranged on the outer circumferential side wall of the first air suction pipe close to the smoking pipe, a first connecting pipe is integrally arranged on the smoking pipe, the first connecting pipe and the smoking pipe are communicated with each other, a first internal thread is arranged on the inner circumferential side wall of the first connecting pipe far away from the smoking pipe, the first external thread and the first internal thread are mutually matched and in threaded connection, a second external thread is arranged on the outer circumferential side wall of the second air suction pipe close to the smoke delivery main pipe, a second connecting pipe is integrally arranged on the smoke delivery main pipe, the second connecting pipe and the smoke delivery main pipe are mutually communicated, a second internal thread is arranged on the inner circumferential side wall of the second connecting pipe far away from the smoke delivery main pipe, and the second external thread and the second internal thread are mutually matched and in threaded connection.

By adopting the technical scheme, the first air suction pipe is connected to the smoke suction pipe through threads, and the second air suction pipe is connected to the smoke delivery main pipe through threads.

Optionally, a first limit ring is fixedly connected to the inner circumferential side wall of the first connecting pipe, the first limit ring is close to a first sealing ring fixedly connected to one side of the first air suction pipe, the first air suction pipe extends into one end of the first connecting pipe and abuts against the first sealing ring, a second limit ring is fixedly connected to the inner circumferential side wall of the second connecting pipe, the second limit ring is close to a second sealing ring fixedly connected to one side of the second air suction pipe, and the second air suction pipe extends into one end of the second connecting pipe and abuts against the second sealing ring.

By adopting the technical scheme, the arrangement of the first limiting ring and the first sealing ring can seal the first air suction pipe and the smoke suction pipe when the first air suction pipe is connected to the smoke suction pipe, so that the air in the first air suction pipe is not easy to flow out from a gap between the first air suction pipe and the smoke suction pipe, and the sealing performance of the first air suction pipe and the smoke suction pipe is improved; the setting of second spacing ring and second sealing ring for the second air inhales the pipe and send the cigarette house steward to seal when the second air inhales the union coupling on sending the cigarette house steward, make the air of second air inhales the pipe and is difficult for flowing out in the gap from second air inhales the pipe and send the cigarette house steward, improved the leakproofness of second air inhales the pipe and send the cigarette house steward.

Optionally, a first cover plate covering one end of the first connecting pipe far away from the smoking pipe is arranged on the first connecting pipe, the first cover plate is in threaded connection with the first connecting pipe, a second cover plate covering one end of the second connecting pipe far away from the smoke delivery main pipe is arranged on the second connecting pipe, and the second cover plate is in threaded connection with the second connecting pipe.

By adopting the technical scheme, the arrangement of the first cover plate and the second cover plate ensures that the smoking pipe and the smoke delivery main pipe can be sealed when the first air suction pipe and the second air suction pipe are not installed, and the sealing performance of the smoking pipe and the smoke delivery main pipe is improved.

Optionally, a first connecting rope is wound on the outer side wall of the first connecting pipe, one end, far away from the first connecting pipe, of the first connecting rope is fixedly connected to the first cover plate, a second connecting rope is wound on the outer side wall of the second connecting pipe, and one end, far away from the second connecting pipe, of the second connecting rope is fixedly connected to the second cover plate.

Adopt above-mentioned technical scheme, the setting of rope is connected to first connecting rope and second for first apron and second apron are difficult for breaking away from and losing from first connecting pipe and second connecting pipe when not using, have improved the life of first apron and second apron.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the arrangement of the flue gas circulating component has simple structure, does not influence the heat efficiency of the flame heating furnace, and does not change the heat distribution ratio of the radiation chamber and the convection chamber;

2. the arrangement of the first air suction pipe and the second air suction pipe reduces the manufacturing cost of the smoke circulating assembly and reduces the production cost.

Drawings

FIG. 1 is a schematic diagram of a device for reducing NOx emissions through flue gas recirculation according to an embodiment of the present application.

Fig. 2 is an exploded view of the smoking pipe and the first air intake pipe in the embodiment of the present application.

FIG. 3 is a plan view of the smoking pipe and the first air intake pipe in the embodiment of the present application.

Fig. 4 is a sectional view taken along the line a-a in fig. 3.

Figure 5 is an exploded view of the smoke delivery manifold and the second air intake tube in an embodiment of the present application.

Figure 6 is a top view of a smoke delivery manifold and a second air intake duct in an embodiment of the present application.

Fig. 7 is a sectional view taken along line B-B in fig. 6.

Fig. 8 is a schematic view of a flame heating furnace in the related art.

Description of reference numerals: 1. a radiation chamber; 11. a burner; 2. a convection chamber; 21. an induced draft fan; 3. a flue gas circulation assembly; 31. a smoking pipe; 311. a first connecting pipe; 3111. a first internal thread; 3112. a first connecting rope; 3113. a first cover plate; 31131. a first connection portion; 311311, a third external thread; 31132. a first covering part; 3114. a first limit ring; 3115. a first seal ring; 32. a first air suction pipe; 321. a first valve; 322. a first external thread; 33. a circulating fan; 34. a smoke delivery main pipe; 341. a second connecting pipe; 3411. a second internal thread; 3412. a second connecting rope; 3413. a second cover plate; 34131. a second connecting portion; 341311, fourth external thread; 34132. a second covering part; 3414. a second stop collar; 3415. a second seal ring; 35. a second air suction pipe; 351. a second valve; 352. a second external thread; 36. a smoke delivery branch pipe.

Detailed Description

The present application is described in further detail below with reference to figures 1-7.

The embodiment of the application discloses a device for reducing NOx emission through flue gas recirculation. Referring to fig. 1, the flue gas recirculation NOx emission reduction apparatus comprises a radiant chamber 1, a convection chamber 2 and a flue gas recirculation assembly 3.

Referring to fig. 1, a burner 11 is installed in a radiation chamber 1 to perform heating. Convection current room 2 and radiation chamber 1 intercommunication each other, and draught fan 21 is installed to the upside of convection current room 2 for the flue gas that radiation chamber 1 flows to in the convection current room 2 receives the effect of draught fan 21 and discharges from the upside of convection current room 2.

Referring to fig. 1, the smoke circulation module 3 includes a smoking pipe 31, a first air suction pipe 32, a circulation fan 33, a smoke delivery main pipe 34, a second air suction pipe 35, and a smoke delivery branch pipe 36. One end of the smoke suction pipe 31 communicates with the radiation chamber 1 to recover a certain amount of NOx gas. The first air suction pipe 32 is mounted on the smoking pipe 31.

Referring to fig. 2, a first connection pipe 311 is integrally disposed on the smoking pipe 31, the first connection pipe 311 and the smoking pipe 31 are communicated with each other, the first connection pipe 311 and the smoking pipe 31 are vertically disposed, a first internal thread 3111 is disposed on an inner circumferential sidewall of the first connection pipe 311 away from the smoking pipe 31, a first external thread 322 is disposed on an outer circumferential sidewall of the first air suction pipe 32 close to the smoking pipe 31, and the first internal thread 3111 is matched with the first external thread 322, so that the first air suction pipe 32 is threadedly connected to the first connection pipe 311. A first valve 321 is further installed on the first air suction pipe 32 to open and close the air of the first air pipe entering the first connection pipe 311. A first connection rope 3112 is further wound around an outer side wall of the first connection pipe 311, a first cover 3113 is fixedly connected to an end of the first connection rope 3112, which is away from the first connection pipe 311, the first cover 3113 includes a first connection portion 31131 and a first cover-closing portion 31132, the first connection portion 31131 is disposed in a cylinder, a third external thread 311311 is disposed on a peripheral side wall of the first connection portion 31131, the third external thread 311311 is matched with the first internal thread 3111, so that the first connection portion 31131 is screwed to the first connection pipe 311, the first cover-closing portion 31132 is fixedly connected to a side of the first connection portion 31131, which is away from the smoke-absorbing pipe 31, and the first cover-closing portion 31132 abuts against an end of the first connection portion 31131, which is away from the smoke-absorbing pipe 31, so that the first connection pipe 311 is sealed when the first air-absorbing pipe 32 is not in use.

Referring to fig. 3 and 4, a first stopper ring 3114 is fixedly coupled to an inner circumferential sidewall of the first connection pipe 311, and the first stopper ring 3114 and the first connection pipe 311 are coaxially disposed. One side of the first spacing ring 3114, which is far away from the smoking pipe 31, is fixedly connected with a first sealing ring 3115, the first sealing ring 3115 and the first spacing ring 3114 are coaxially arranged, the first sealing ring 3115 is made of a flexible material, and the first sealing ring 3115 is made of a rubber material. When the first air suction pipe 32 is screw-coupled to the first connection pipe 311, one end of the first air suction pipe 32 extending into the first connection pipe 311 abuts on the first sealing ring 3115, so that the first air suction pipe 32 and the first connection pipe 311 are sealed.

Referring to fig. 1, one end of the smoke absorbing pipe 31 away from the radiation chamber 1 is installed on an air inlet of the circulating fan 33 and is communicated with the circulating fan 33. One end of the smoke delivery main pipe 34 is installed on the air outlet of the circulating fan 33, so that the smoke in the smoking pipe 31 is delivered into the smoke delivery main pipe 34 through the circulating fan 33.

Referring to fig. 5, the smoke feeding main pipe 34 is integrally provided with a second connecting pipe 341, the second connecting pipe 341 is communicated with the smoke feeding main pipe 34, the second connecting pipe 341 and the smoke feeding main pipe 34 are vertically arranged, the inner circumferential side wall of the second connecting pipe 341 away from the smoke feeding main pipe 34 is provided with a second internal thread 3411, the outer circumferential side wall of the second air suction pipe 35 close to the smoke feeding main pipe 34 is provided with a second external thread 352, and the second internal thread 3411 is matched with the second external thread 352, so that the second air suction pipe 35 is screwed to the second connecting pipe 341. A second valve 351 is further installed on the second air suction pipe 35 to open and close the air of the second air pipe entering the second connection pipe 341. A second connecting rope 3412 is further wound around the outer side wall of the second connecting pipe 341, a second cover 3413 is fixedly connected to an end of the second connecting rope 3412 away from the second connecting pipe 341, the second cover 3413 includes a second connecting portion 34131 and a second closing portion 34132, the second connecting portion 34131 is cylindrical, a fourth external thread 341311 is provided on the outer circumferential side wall of the second connecting portion 34131, the fourth external thread 341311 is matched with the second internal thread 3411, so that the second connecting portion 34131 is screwed to the second connecting pipe 341, the second closing portion 34132 is fixedly connected to a side of the second connecting portion 31 away from the smoke feeding main pipe 34, and the second closing portion 34132 abuts against an end of the second connecting portion 34131 away from the smoke feeding main pipe 34, so that the second connecting pipe 341 is sealed when the second air suction pipe 35 is not in use.

Referring to fig. 6 and 7, a second stopper ring 3414 is fixedly coupled to an inner circumferential sidewall of the second connection pipe 341, and the second stopper ring 3414 and the second connection pipe 341 are coaxially disposed. A second sealing ring 3415 is fixedly connected to a side of the second stopper ring 3414 away from the smoke feeding manifold 34, the second sealing ring 3415 and the second stopper ring 3414 are coaxially disposed, the second sealing ring 3415 is made of a flexible material, and the second sealing ring 3415 is made of a rubber material. When the second air suction pipe 35 is screwed to the second connection pipe 341, one end of the second air suction pipe 35 extending into the second connection pipe 341 abuts against the second sealing ring 3415, so that the second air suction pipe 35 and the second connection pipe 341 are sealed.

The smoke delivery branch pipes 36 are fixedly connected to the smoke delivery main pipe 34 and are communicated with the smoke delivery main pipe 34, the number of the smoke delivery branch pipes 36 is consistent with that of the burners 11, one ends, far away from the smoke delivery main pipe 34, of the smoke delivery branch pipes 36 are connected to the lower side of the radiation chamber 1 and are communicated with the radiation chamber 1, and smoke mixed air in the smoke delivery branch pipes 36 flows to the burners 11 to reduce the oxygen content of the mixed combustion air.

The implementation principle of the device for reducing NOx emission through flue gas recirculation in the embodiment of the application is as follows: the high-temperature flue gas in the radiation chamber 1 is sucked out through the smoke suction pipe 31, meanwhile, a certain amount of fresh air is sucked in through the first air suction pipe 32, so that the temperature of the high-temperature flue gas is reduced by a part, and then the high-temperature flue gas is converged into the circulating fan 33, the circulating fan 33 sends the flue gas into the smoke feeding main pipe 34, and then a certain amount of fresh air is sucked in through the second air suction pipe 35, so that the oxygen content entering the radiation chamber 1 is controlled, and the emission value of NOx gas is reduced.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims (7)

1. A device for reducing NOx emissions by means of flue gas recirculation, comprising a radiant chamber (1) and a convection chamber (2), a burner (11) being arranged below the radiant chamber (1), the convection chamber (2) being in communication with the radiant chamber (1), characterized in that: still include flue gas circulation subassembly (3), flue gas circulation subassembly (3) are including smoking pipe (31), circulating fan (33), send cigarette house steward (34) and a plurality of branch pipe of sending cigarette (36), the exit of radiation room (1) is located to the one end of smoking pipe (31) and communicates with each other with radiation room (1), the air intake of circulating fan (33) and the other end intercommunication of smoking pipe (31), send the air outlet intercommunication of cigarette house steward (34) and circulating fan (33), a plurality of send cigarette branch pipe (36) all communicate with sending cigarette house steward (34) each other, send the one end and the combustor (11) intercommunication that cigarette house steward (34) were kept away from to cigarette branch pipe (36).

2. The flue gas recirculation NOx emissions reduction device of claim 1, wherein: the smoking pipe (31) is provided with a first air suction pipe (32), and the first air suction pipe (32) is communicated with the smoking pipe (31).

3. The flue gas recirculation NOx emissions reduction device of claim 2, wherein: the smoke delivery main pipe (34) is provided with a second air suction pipe (35), and the second air suction pipe (35) is communicated with the smoke suction pipe (31).

4. The flue gas recirculation NOx emissions reduction device of claim 3, wherein: a first external thread (322) is arranged on the outer circumferential side wall of the first air suction pipe (32) close to the smoking pipe (31), a first connecting pipe (311) is integrally arranged on the smoking pipe (31), the first connecting pipe (311) is communicated with the smoking pipe (31), a first internal thread (3111) is arranged on the inner circumferential side wall of the first connecting pipe (311) far away from the smoking pipe (31), the first external thread (322) is matched with the first internal thread (3111) in a threaded connection mode, a second external thread (352) is arranged on the outer circumferential side wall of the second air suction pipe (35) close to the smoke delivery main pipe (34), a second connecting pipe (341) is integrally arranged on the smoke delivery main pipe (34), the second connecting pipe (341) is communicated with the smoke delivery main pipe (34), and a second internal thread (3411) is arranged on the inner circumferential side wall of the second connecting pipe (341) far away from the smoke delivery main pipe (34), the second external thread (352) and the second internal thread (3411) are engaged and screwed with each other.

5. The flue gas recirculation NOx emissions reduction device of claim 4, wherein: fixedly connected with first spacing ring (3114) on the interior circumferential side wall of first connecting pipe (311), first spacing ring (3114) are close to first air suction pipe (32) one side fixedly connected with first sealing ring (3115), first air suction pipe (32) stretch into the one end butt of first connecting pipe (311) on first sealing ring (3115), fixedly connected with second spacing ring (3414) on the interior circumferential side wall of second connecting pipe (341), second spacing ring (3414) are close to second air suction pipe (35) one side fixedly connected with second sealing ring (3415), the one end butt that second air suction pipe (35) stretch into second connecting pipe (341) is on second sealing ring (3415).

6. The flue gas recirculation NOx emissions reduction device of claim 5, wherein: be equipped with on first connecting pipe (311) and cover first connecting pipe (311) and close first apron (3113) of the one end of smoking pipe (31) of keeping away from, first apron (3113) and first connecting pipe (311) threaded connection, be equipped with on second connecting pipe (341) and cover second connecting pipe (341) and keep away from second apron (3413) of the one end of sending cigarette house steward (34), second apron (3413) and second connecting pipe (341) threaded connection.

7. The flue gas recirculation NOx emissions reduction device of claim 6, wherein: the outer side wall of the first connecting pipe (311) is provided with a first connecting rope (3112) in a winding manner, one end, far away from the first connecting pipe (311), of the first connecting rope (3112) is fixedly connected to the first cover plate (3113), the outer side wall of the second connecting pipe (341) is provided with a second connecting rope (3412) in a winding manner, and one end, far away from the second connecting pipe (341), of the second connecting rope (3412) is fixedly connected to the second cover plate (3413).

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