A double-vortex flue gas recirculation structure

Abstract

The utility model relates to flue gas recirculation technical field especially a kind of double-vortex flue gas recirculation structure, comprising: flue gas circulation assembly, including incinerator, front arch upper layer flue gas recirculation branch pipe and front and rear wall lower layer flue gas recirculation branch pipe being arranged in the inside of incinerator and the flue gas recirculation main pipe being arranged in the outside of incinerator and being connected with front arch upper layer flue gas recirculation branch pipe and front and rear wall lower layer flue gas recirculation branch pipe;The inside of incinerator is provided with front arch lower layer header and nozzle, front arch upper layer header and nozzle, front and rear wall lower layer header and nozzle and front and rear wall upper layer header and nozzle, the outside of incinerator is provided with secondary air main pipe, front arch lower layer secondary air branch pipe, front arch upper layer secondary air branch pipe, front and rear wall lower layer secondary air branch pipe and front and rear wall upper layer secondary air branch pipe are sequentially and communicatively arranged on the secondary air main pipe;In the full mixing and uniform distribution of temperature and airflow in nozzle rear area in furnace, it is helpful to gas combustion.

Description

Technical Field

[0001] This utility model relates to the field of flue gas recirculation technology, and in particular to a dual-vortex flue gas recirculation structure. Background Technology

[0002] With increasingly stringent NOx emission and NH3 escape limits, flue gas recirculation technology can effectively reduce furnace temperature and oxygen content, thereby reducing NOx generation at the incinerator outlet and the use of subsequent denitrification agents, and is being adopted by more and more waste incineration plants.

[0003] The flue gas recirculation system process involves adding a bypass flue by opening holes in the flue at the outlet of the bag filter, the inlet or outlet of the induced draft fan, etc. A portion of the purified flue gas is drawn out by the flue gas recirculation fan and sent into the incinerator through the flue gas recirculation pipeline.

[0004] Recirculated flue gas and secondary air both play an important role in the combustion of the incinerator. How to better mix the flue gas and air and improve the combustion stability and efficiency is an issue that flue gas recirculation systems need to continuously focus on. To this end, a dual-vortex flue gas recirculation structure is proposed. Utility Model Content

[0005] Given that recirculated flue gas and secondary air play important roles in the combustion of incinerators in the above-mentioned or existing technologies, how to better mix flue gas and air to improve combustion stability and efficiency is an issue that flue gas recirculation systems need to continuously focus on, and this utility model is proposed.

[0006] Therefore, the purpose of this invention is to provide a dual-vortex flue gas recirculation structure.

[0007] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0008] A dual-vortex flue gas recirculation structure includes:

[0009] The flue gas recirculation assembly includes an incinerator, a front arch upper flue gas recirculation branch pipe and a front and rear wall lower flue gas recirculation branch pipe disposed inside the incinerator, and a flue gas recirculation main pipe disposed outside the incinerator and connected to the front arch upper flue gas recirculation branch pipe and the front and rear wall lower flue gas recirculation branch pipe.

[0010] The incinerator is internally equipped with a lower front arch header and nozzle, an upper front arch header and nozzle, a lower front and rear wall header and nozzle, and an upper front and rear wall header and nozzle. The incinerator is externally equipped with a secondary air main pipe. The secondary air main pipe is sequentially connected to the lower front arch secondary air branch pipe, the upper front arch secondary air branch pipe, the lower front and rear wall secondary air branch pipe, and the upper front and rear wall secondary air branch pipe. The lower front arch secondary air branch pipe, the upper front arch secondary air branch pipe, the lower front and rear wall secondary air branch pipe, and the upper front and rear wall secondary air branch pipe are respectively connected to the lower front arch header and nozzle, the upper front arch header and nozzle, the lower front and rear wall header and nozzle, and the upper front and rear wall header and nozzle.

[0011] The dust removal assembly includes a dust removal box located at the inlet end of the flue gas recirculation main pipe, a filter element located inside the dust removal box, a cleaning element and a vibrating element located inside the dust removal box and adjacent to the filter element, and a driving element located inside the dust removal box. The driving element enables intermittent contact between the cleaning element and the vibrating element and the filter element.

[0012] As a preferred embodiment of the dual-vortex flue gas recirculation structure of this utility model, an expansion joint, a flow meter, and a damper are sequentially installed on the upper flue gas recirculation branch pipe of the front arch, the lower flue gas recirculation branch pipe of the front and rear walls, the lower secondary air branch pipe of the front arch, the upper secondary air branch pipe of the front arch, the lower secondary air branch pipe of the front and rear walls, and the upper secondary air branch pipe of the front and rear walls.

[0013] As a preferred embodiment of the dual-vortex flue gas recirculation structure of this utility model, the filter element includes a mounting frame and a filter plate. The mounting frame has two units symmetrically distributed at both ends of the dust collection box. The filter plate is detachably installed inside the mounting frame.

[0014] As a preferred embodiment of the dual-vortex flue gas recirculation structure of this utility model, the driving component includes a support frame, a lead screw sleeve, and a ball screw. The support frame is connected to the inner top of the dust collector, the lead screw sleeve is connected to the outer wall of the support frame, and the ball screw passes through the lead screw sleeve and cooperates with each other.

[0015] As a preferred embodiment of the dual-vortex flue gas recirculation structure of this utility model, the driving component further includes a crankshaft rotatably disposed at the top of the dust collector, the bottom end of the crankshaft being rotatably disposed at the bottom of the support frame, a bearing seat being rotatably disposed at one end of the ball screw facing the crankshaft, and a connecting rod being disposed between the bearing seat and the crankshaft, with both ends of the connecting rod being rotatably connected.

[0016] As a preferred embodiment of the dual-vortex flue gas recirculation structure of this utility model, the cleaning component includes a cleaning brush connected to the end of the ball screw.

[0017] As a preferred embodiment of the dual-vortex flue gas recirculation structure of this utility model, the vibrating element includes a square frame rotatably disposed on the outer wall of the ball screw, the square frame being slidably connected to the inner wall of the dust collector, an elastic strip being disposed on the outer wall of the mounting bracket facing the square frame, a magnetic ball head being disposed at the end of the elastic strip, and a strong magnet being disposed on the outer wall of the square frame corresponding to the magnetic ball head.

[0018] As a preferred embodiment of the dual-vortex flue gas recirculation structure of this utility model, the dust collector is provided with connecting flanges at both ends, and a dust collection hopper is connected to the bottom of the dust collector.

[0019] The beneficial effects of the dual-vortex flue gas recirculation structure of this utility model are as follows: This utility model arranges four layers of flue gas recirculation and secondary air nozzles in the front arch and front and rear walls of the incinerator, and adopts a dual-vortex arrangement. The nozzle angles are at opposite corner positions, and the installation angle of each nozzle is different. This can effectively disturb and mix the flue gas generated by incineration, realize the upward airflow of the dual-vortex flow, achieve full mixing and uniform distribution of temperature and airflow in the area behind the nozzles in the furnace, and extend the flue gas residence time and improve the gas combustion effect, which helps to fully combust the gas and improve combustion stability and efficiency.

[0020] By using a drive mechanism to achieve intermittent contact between the cleaning and vibrating components and the filter, the cleaning and vibrating components can effectively clean the filter. This dual approach ensures that the filter will not easily become clogged, increasing the working time of the dust removal components. It also reduces the contact time between the cleaning and vibrating components and the filter, slowing down wear and extending the service life of the cleaning components, while avoiding interference with the use of the filter. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a dual-vortex flue gas recirculation structure.

[0023] Figure 2 This is a schematic diagram of a dust collector with a dual-vortex flue gas recirculation structure.

[0024] Figure 3 This is a schematic diagram of the support frame structure for a dual-vortex flue gas recirculation structure.

[0025] Figure 4 This is a schematic diagram of the mounting frame structure for a dual-vortex flue gas recirculation structure.

[0026] Figure 5 This is a schematic diagram of the crankshaft structure for a dual-vortex flue gas recirculation system.

[0027] The components include: 1. Incinerator; 2. Flue gas recirculation main pipe; 3. Upper flue gas recirculation branch pipe of the front arch; 4. Lower flue gas recirculation branch pipe of the front and rear walls; 5. Secondary air main pipe; 6. Lower secondary air branch pipe of the front arch; 7. Upper secondary air branch pipe of the front arch; 8. Lower secondary air branch pipe of the front and rear walls; 9. Upper secondary air branch pipe of the front and rear walls; 10. Lower header and nozzle of the front arch; 11. Upper header and nozzle of the front arch; 12. Lower header and nozzle of the front and rear walls. ; 13. Front and rear wall upper headers and nozzles; 14. Expansion joint; 15. Flow meter; 16. Damper; 17. Dust collector; 18. Connecting flange; 19. Dust hopper; 20. Mounting bracket; 21. Filter plate; 22. Crankshaft; 23. Support frame; 24. Square frame; 25. Elastic strip; 26. Magnetic ball head; 27. Strong magnet; 28. Screw sleeve; 29. ​​Ball screw; 30. Cleaning brush; 31. Connecting rod; 32. Shaft seat. Detailed Implementation

[0028] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0029] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0030] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments.

[0031] Example 1

[0032] Reference Figure 1 This is the first embodiment of the present invention. This embodiment provides a double vortex flue gas recirculation structure, which can achieve full mixing and uniform distribution of recirculated flue gas, secondary air and flue gas generated by incinerator 1, improve combustion stability and efficiency, and at the same time improve denitrification efficiency.

[0033] Specifically, the flue gas recirculation assembly includes an incinerator 1, a front arch upper flue gas recirculation branch pipe 3 and a front and rear wall lower flue gas recirculation branch pipe 4 located inside the incinerator 1, and a flue gas recirculation main pipe 2 located outside the incinerator 1 and connected to the front arch upper flue gas recirculation branch pipe 3 and the front and rear wall lower flue gas recirculation branch pipe 4. A bypass flue is added by opening a hole in the flue at the outlet of the dust removal assembly. A portion of the purified flue gas is drawn by a fan and sent into the incinerator 1 through the flue gas recirculation main pipe 2.

[0034] The incinerator 1 is internally equipped with a lower front arch header and nozzle 10, an upper front arch header and nozzle 11, a lower front and rear wall header and nozzle 12, and an upper front and rear wall header and nozzle 13. The incinerator 1 is externally equipped with a secondary air main pipe 5. The secondary air main pipe 5 is sequentially connected to a lower front arch secondary air branch pipe 6, an upper front arch secondary air branch pipe 7, a lower front and rear wall secondary air branch pipe 8, and an upper front and rear wall secondary air branch pipe 9. The lower front arch secondary air branch pipe 6, the upper front arch secondary air branch pipe 7, the lower front and rear wall secondary air branch pipe 8, and the upper front and rear wall secondary air branch pipe 9 are respectively connected to the lower front arch header and nozzle 10, the upper front arch header and nozzle 11, the lower front and rear wall header and nozzle 12, and the upper front and rear wall header and nozzle 13 to achieve the mixing of secondary air and recirculated flue gas to form mixed flue gas.

[0035] Furthermore, expansion joints 14, flow meters 15, and dampers 16 are sequentially installed on the upper flue gas recirculation branch pipe 3 of the front arch, the lower flue gas recirculation branch pipe 4 of the front and rear walls, the lower secondary air branch pipe 6 of the front arch, the upper secondary air branch pipe 7 of the front arch, the lower secondary air branch pipe 8 of the front and rear walls, and the upper secondary air branch pipe 9 of the front and rear walls.

[0036] In use, the lower header and nozzle 10 and the upper header and nozzle 11 of the front arch are installed on the front arch of the incinerator 1. The lower and upper nozzles of the lower header and nozzle 10 are inclined downwards at a certain angle to the front arch of the incinerator 1 and enter the incinerator 1. The lower header and nozzle 12 and the upper header and nozzle 13 of the front and rear walls are installed on the front and rear walls of the incinerator 1. The lower nozzles of the lower header and nozzle 12 are at the same height and enter the incinerator 1 horizontally, adopting a double vortex structure. That is, the center of one nozzle is aligned with the opposite corner of the furnace wall on the other side, and the center of the other nozzle is aligned with the center point of the furnace wall on its own side. The installation angle of each nozzle is different, forming a double vortex. The upper nozzles of the upper header and nozzle 13 of the front and rear walls are arranged in the same way as the lower nozzles of the front wall.

[0037] In summary, four layers of flue gas recirculation and secondary air nozzles are arranged at the front arch and the front and rear walls of incinerator 1. Secondary air is introduced into the lower layer of nozzles at the front arch and the upper layer of nozzles at the front and rear walls. Secondary air and recirculated flue gas are introduced into the upper layer of nozzles at the front arch and the lower layer of nozzles at the front and rear walls simultaneously. The nozzles at the upper and lower layers of the front and rear walls are arranged horizontally in a double vortex configuration with the nozzles at opposite corners. The different installation angles of each nozzle effectively agitate and mix the flue gas generated during incineration, achieving a double vortex upward airflow. This ensures thorough mixing and uniform distribution of temperature and airflow in the area behind the nozzles within the furnace, extends the flue gas residence time, and improves gas combustion efficiency, promoting complete combustion, increasing combustion stability and efficiency, while reducing CO and NOx emissions. The denitrification efficiency can reach 20%-30%.

[0038] Example 2

[0039] Reference Figures 1-5 This is the second embodiment of the present invention. Unlike the previous embodiment, this embodiment provides a dust removal component with a dual-vortex flue gas recirculation structure.

[0040] Specifically, the dust removal assembly includes a dust collection box 17 located at the inlet end of the flue gas recirculation header 2, a filter element located inside the dust collection box 17, a cleaning element and a vibrating element located inside the dust collection box 17 and adjacent to the filter element, and a driving element located inside the dust collection box 17. The driving element enables intermittent contact between the cleaning element and the vibrating element and the filter element. The flue gas passes through the dust collection box 17 and the filter plate 21 of the filter element blocks particulate impurities in the flue gas to achieve the purpose of dust removal.

[0041] The filter element includes a mounting frame 20 and a filter plate 21. The mounting frame 20 has two plates symmetrically distributed at both ends of the interior of the dust collection box 17. The filter plate 21 is detachably installed inside the mounting frame 20. Both ends of the dust collection box 17 are provided with connecting flanges 18. The bottom of the dust collection box 17 is connected to a dust collection hopper 19.

[0042] Furthermore, the driving component includes a support frame 23, a lead screw sleeve 28, and a ball screw 29. The support frame 23 is connected to the inner top of the dust collection box 17, the lead screw sleeve 28 is connected to the outer wall of the support frame 23, and the ball screw 29 penetrates the lead screw sleeve 28 and cooperates with it. Since the lead screw sleeve 28 is fixed, the lead screw sleeve 28 adds the linear motion of the ball screw 29 to the rotational motion.

[0043] The drive unit also includes a crankshaft 22 rotatably mounted on the top of the dust collector 17. The bottom end of the crankshaft 22 is rotatably mounted on the bottom of the support frame 23. A bearing seat 32 is rotatably mounted on one end of the ball screw 29 facing the crankshaft 22. A connecting rod 31 is provided between the bearing seat 32 and the crankshaft 22. Both ends of the connecting rod 31 are rotatably connected. When the crankshaft 22 of the drive unit rotates, the crankshaft 22 drives the ball screw 29 to reciprocate linearly through the connecting rod 31 and the bearing seat 32.

[0044] The cleaning component includes a cleaning brush 30 connected to the end of the ball screw 29. The cleaning brush 30 scrapes away particulate impurities accumulated on the filter plate 21 during rotation, preventing particulate impurities from clogging the filter holes of the filter plate 21.

[0045] The vibrating element includes a square frame 24 rotatably mounted on the outer wall of the ball screw 29. The square frame 24 is slidably connected to the inner wall of the dust collection box 17. An elastic strip 25 is provided on the outer wall of the mounting frame 20 facing the square frame 24. A magnetic ball head 26 is provided at the end of the elastic strip 25. A strong magnet 27 is provided on the outer wall of the square frame 24 corresponding to the magnetic ball head 26. The strong magnet 27 on the square frame 24 is magnetically connected to the magnetic ball head 2 of the vibrating element. Therefore, the movement of the square frame 24 is transmitted to the elastic strip 25, causing it to deform. Until the tension of the elastic strip 25 on the magnetic ball head 2 is greater than the magnetic attraction between the magnetic ball head 2 and the strong magnet 27, the magnetic ball head 2 disengages from the strong magnet 27. The elastic strip 25 then resets and, under inertia, the magnetic ball head 2 strikes the mounting frame 20. The filter plate 21 shakes off the accumulated particulate impurities under vibration, preventing the particulate impurities from clogging the filter holes of the filter plate 21.

[0046] The rest of the structure is the same as in Example 1.

[0047] During use, flue gas passes through the dust collector 17 and is blocked by the filter plate 21 of the filter element to achieve dust removal. After the filter plate 21 has been used for a period of time, the crankshaft 22 of the control drive component rotates. The crankshaft 22 drives the ball screw 29 to reciprocate linearly through the connecting rod 31 and the bearing seat 32. Both ends of the connecting rod 31 are rotatably connected to adapt to the circumferential motion of the crankshaft 22. Since the screw sleeve 28 is fixed to the outer wall of the support frame 23, the screw sleeve 28 adds rotational motion to the linear motion of the ball screw 29. The bearing seat 32 and the ball screw 29 are rotatably connected, and the bearing seat 32 will not interfere with the rotational motion. The rotation of the ball screw 29 and its linear motion drive the frame 24 and cleaning brush 30 closer to the filter plate 21. When the movement reaches the end, the strong magnet 27 on the frame 24 contacts the magnetic ball head 2 of the vibrating element. At the same time, the cleaning brush 30 gradually contacts the surface of the filter plate 21. The ball screw 29 pulls the frame 24 and cleaning brush 30 away from the filter plate 21 in a back-and-forth motion. The rotation of the ball screw 29 drives the cleaning brush 30 to move in a circular motion relative to the surface of the filter plate 21. During the rotation, the cleaning brush 30 scrapes away the particulate impurities accumulated on the filter plate 21 to prevent the particulate impurities from clogging the filter holes of the filter plate 21.

[0048] Since the strong magnet 27 on the frame 24 is magnetically connected to the magnetic ball head 2 of the vibrating element, the movement of the frame 24 is transmitted to the elastic strip 25, causing it to deform. Until the tension of the elastic strip 25 on the magnetic ball head 2 is greater than the magnetic attraction between the magnetic ball head 2 and the strong magnet 27, the magnetic ball head 2 disengages from the strong magnet 27, and the elastic strip 25 resets and, under inertia, the magnetic ball head 2 strikes the mounting frame 20. The filter plate 21 shakes off the accumulated particulate impurities under vibration, preventing particulate impurities from clogging the filter holes of the filter plate 21. This dual approach ensures that the filter plate 21 will not easily become clogged, thus increasing the working time of the dust removal component.

[0049] In summary, by using a drive mechanism to achieve intermittent contact between the cleaning and vibrating components and the filter element, the cleaning and vibrating components can effectively clean the filter element while reducing the contact time between them. This slows down wear, extends the service life of the cleaning components, and avoids interfering with the use of the filter element.

[0050] It should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A dual-vortex flue gas recirculation structure, characterized in that, include: The flue gas recirculation assembly includes an incinerator (1), a front arch upper flue gas recirculation branch pipe (3) and a front and rear wall lower flue gas recirculation branch pipe (4) disposed inside the incinerator (1), and a flue gas recirculation main pipe (2) disposed outside the incinerator (1) and connected to the front arch upper flue gas recirculation branch pipe (3) and the front and rear wall lower flue gas recirculation branch pipe (4). The incinerator (1) is equipped with a front arch lower layer header and nozzle (10), a front arch upper layer header and nozzle (11), a front and rear wall lower layer header and nozzle (12), and a front and rear wall upper layer header and nozzle (13). The incinerator (1) is equipped with a secondary air main pipe (5). The secondary air main pipe (5) is connected in sequence with a front arch lower layer secondary air branch pipe (6), a front arch upper layer secondary air branch pipe (7), a front and rear wall lower layer secondary air branch pipe (8), and a front and rear wall upper layer secondary air branch pipe (9). The front arch lower layer secondary air branch pipe (6), the front arch upper layer secondary air branch pipe (7), the front and rear wall lower layer secondary air branch pipe (8), and the front and rear wall upper layer secondary air branch pipe (9) are respectively connected to the front arch lower layer header and nozzle (10), the front arch upper layer header and nozzle (11), the front and rear wall lower layer header and nozzle (12), and the front and rear wall upper layer header and nozzle (13). The dust removal assembly includes a dust removal box (17) located at the air inlet of the flue gas recirculation main pipe (2), a filter element located inside the dust removal box (17), a cleaning element and a vibrating element located inside the dust removal box (17) and adjacent to the filter element, and a driving element located inside the dust removal box (17). The driving element enables intermittent contact between the cleaning element and the vibrating element and the filter element.

2. The dual-vortex flue gas recirculation structure as described in claim 1, characterized in that: Expansion joints (14), flow meters (15) and dampers (16) are sequentially installed on the upper flue gas recirculation branch pipe (3) of the front arch, the lower flue gas recirculation branch pipe (4) of the front and rear walls, the lower secondary air branch pipe (6) of the front arch, the upper secondary air branch pipe (7) of the front arch, the lower secondary air branch pipe (8) of the front and rear walls and the upper secondary air branch pipe (9) of the front and rear walls.

3. The dual-vortex flue gas recirculation structure as described in claim 2, characterized in that: The filter element includes a mounting frame (20) and a filter plate (21). The mounting frame (20) has two plates symmetrically distributed at both ends of the interior of the dust collection box (17). The filter plate (21) is detachably installed inside the mounting frame (20).

4. The dual-vortex flue gas recirculation structure as described in claim 3, characterized in that: The drive unit includes a support frame (23), a lead screw sleeve (28), and a ball screw (29). The support frame (23) is connected to the inner top of the dust collection box (17), the lead screw sleeve (28) is connected to the outer wall of the support frame (23), and the ball screw (29) penetrates the lead screw sleeve (28) and cooperates with each other.

5. The dual-vortex flue gas recirculation structure as described in claim 4, characterized in that: The drive unit also includes a crankshaft (22) rotatably disposed at the top of the dust collector (17), the bottom end of the crankshaft (22) rotatably disposed at the bottom of the support frame (23), the ball screw (29) is rotatably disposed at one end facing the crankshaft (22) with a bearing seat (32), and a connecting rod (31) is disposed between the bearing seat (32) and the crankshaft (22), both ends of the connecting rod (31) being rotatably connected.

6. The dual-vortex flue gas recirculation structure as described in claim 5, characterized in that: The cleaning component includes a cleaning brush (30) connected to the end of the ball screw (29).

7. The dual-vortex flue gas recirculation structure as described in claim 6, characterized in that: The vibrating element includes a square frame (24) rotatably mounted on the outer wall of the ball screw (29). The square frame (24) is slidably connected to the inner wall of the dust collection box (17). An elastic strip (25) is provided on the outer wall of the mounting bracket (20) facing the square frame (24). A magnetic ball head (26) is provided at the end of the elastic strip (25). A strong magnet (27) is provided on the outer wall of the square frame (24) corresponding to the magnetic ball head (26).

8. The dual-vortex flue gas recirculation structure as described in claim 7, characterized in that: Both ends of the dust collector (17) are provided with connecting flanges (18), and the bottom of the dust collector (17) is connected to a dust collection hopper (19).

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