Flue gas waste heat recovery device of gas-fired boiler

Abstract

The invention relates to the technical field of flue gas waste heat recovery, and provides a gas-fired boiler flue gas waste heat recovery device which comprises a heat exchange spray tower, and further comprises a fixed disc, a spray mechanism, a gas inlet mechanism, a positioning ring, a filter cartridge, a mounting mechanism and a water drainage mechanism, and a plurality of supporting legs are fixedly arranged at the bottom end of the heat exchange spray tower. The fixing disc is fixedly arranged in the heat exchange spraying tower, a plurality of ventilation openings are formed in the fixing disc, the spraying mechanism is arranged on the fixing disc and used for spraying heat exchange liquid into the heat exchange spraying tower and conducting heat exchange on boiler flue gas through the heat exchange liquid, and the gas inlet mechanism is arranged in the heat exchange spraying tower and used for introducing the boiler flue gas into the heat exchange spraying tower. By means of the technical scheme, the technical problem that in the prior art, impurities in flue gas can enter a follow-up circulating system along with heat exchange liquid in the heat exchange process, and consequently energy consumption is increased is solved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of flue gas waste heat recovery technology, specifically, to a flue gas waste heat recovery device for a gas-fired boiler. Background Technology

[0002] Against the backdrop of energy scarcity and increasingly stringent environmental protection requirements, gas-fired boilers, as major energy consumers, have made flue gas waste heat recovery technology a key means to improve energy utilization efficiency and reduce carbon emissions. Among these methods, the use of heat exchange spray towers for flue gas waste heat recovery is widely used due to its sufficient gas-liquid contact and high heat exchange efficiency. High-temperature flue gas enters from the bottom of the tower and comes into countercurrent contact with low-temperature heat exchange liquid (mostly water or a mixture containing additives) sprayed from the top of the tower. Through direct heat exchange, the flue gas is cooled, and the heat exchange liquid absorbs heat and enters subsequent systems (such as boiler feedwater preheating, domestic hot water supply, etc.), thus completing the secondary utilization of waste heat. However, in actual operation, the flue gas from gas-fired boilers is not completely clean. It may carry fine dust generated during combustion, unburned carbon particles, and impurities such as salt crystals formed by the reaction of acidic components in the flue gas with the spray liquid. After these impurities mix with the heat exchange liquid in the heat exchange spray tower, they will enter the circulation system with the heat exchange liquid. These impurities are prone to depositing on the surface of the circulation pipes and water pump impellers, reducing heat exchange efficiency and increasing system energy consumption. Summary of the Invention

[0003] To overcome the above-mentioned defects, the present invention provides a waste heat recovery device for flue gas from a gas-fired boiler, which solves the technical problem in the prior art that impurities in the flue gas will enter the subsequent circulation system along with the heat exchange liquid during the heat exchange process, thereby increasing energy consumption.

[0004] According to one aspect, at least one embodiment of the present invention provides a waste heat recovery device for flue gas from a gas-fired boiler, including a heat exchange spray tower. The heat exchange spray tower has multiple supporting legs fixedly installed at its bottom end. It also includes a fixing plate, a spraying mechanism, an air inlet mechanism, a positioning ring, a filter cylinder, an installation mechanism, and a drainage mechanism. The fixing plate is fixedly installed inside the heat exchange spray tower and has multiple air vents. The spraying mechanism is installed on the fixing plate and is used to spray heat exchange liquid into the heat exchange spray tower for heat exchange of the boiler flue gas. The air inlet mechanism is installed inside the heat exchange spray tower and is used to introduce boiler flue gas into the heat exchange spray tower. The positioning ring is fixedly installed on the inner wall of the heat exchange spray tower. The filter cylinder is installed inside the heat exchange spray tower. The installation mechanism is installed inside the heat exchange spray tower and is used to install and fix the filter cylinder. The drainage mechanism is installed inside the heat exchange spray tower and is used to introduce the heat exchange liquid after heat exchange into the filter cylinder.

[0005] Preferably, the spraying mechanism includes a first housing, a water inlet pipe, a second housing, spray pipes, nozzles, and a first rotating mechanism. The bottom end of the fixed plate is fixedly provided with an annular first housing. The water inlet pipe passes through the side wall of the heat exchange spray tower and communicates with the first housing. The second housing is fixedly provided on the bottom side wall of the fixed plate. A plurality of spray pipes are rotatably arranged between the inner wall of the second housing and the first housing. One end of the spray pipe communicates with the first housing, and the other end of the spray pipe is sealed and extends into the second housing. A plurality of nozzles are provided in communication with the side wall of the spray pipe. The first rotating mechanism is provided on the second housing and is used to drive the spray pipe to rotate.

[0006] Furthermore, the first rotating mechanism includes a first bevel gear, a second bevel gear, and a driving mechanism. The first bevel gear is fixedly disposed at the end of the spray pipe away from the first housing. The second bevel gear is rotatably disposed on the inner top wall of the second housing and meshes with the first bevel gear. The driving mechanism is disposed on the fixed disk and is used to drive the second bevel gear to rotate.

[0007] Furthermore, the driving mechanism includes a first cavity, a driving column, a first gear ring, a first gear, and a first motor. The first cavity is formed within the fixed disk. The driving column is fixedly mounted on the second bevel gear. Both ends of the driving column extend out of the second housing and are rotatably and sealingly connected to the sidewalls of the second housing. The top end of the driving column extends into the first cavity and is rotatably connected to the inner top wall of the first cavity. The first gear ring is fixedly mounted on the outer wall of the driving column. The first gear is rotatably mounted within the first cavity and meshes with the first gear ring. The first motor is mounted on the fixed disk, and the output end of the first motor is fixedly connected to the first gear.

[0008] Furthermore, the air intake mechanism includes a first air intake pipe, a second air intake pipe, and an air intake hose. The first air intake pipe is fixedly installed at the bottom end of the drive column, and both ends of the first air intake pipe are sealed. A plurality of second air intake pipes are fixedly installed on the side wall of the first air intake pipe. A plurality of air intake holes are opened on the bottom side wall of the second air intake pipe. A rotary joint is connected to the bottom end of the first air intake pipe. The air intake hose is installed at the end of the rotary joint away from the first air intake pipe. The end of the air intake hose away from the rotary joint extends out of the heat exchange spray tower.

[0009] Based on the above scheme, the installation mechanism includes an installation port, an installation plate, and a positioning plate. The installation port is opened on the inner bottom wall of the heat exchange spray tower. The inner wall of the installation port is provided with internal threads, and the outer wall of the installation plate is provided with external threads. The installation plate extends into the installation port through threaded engagement. The positioning plate is fixedly installed on the top side wall of the installation plate. The two ends of the filter cylinder are in contact with the positioning ring and the installation plate, respectively. The air inlet hose passes through the positioning plate and the installation plate.

[0010] Based on the above scheme, the drainage mechanism includes a water tank and a drainage pipe. The water tank is fixedly installed inside the heat exchange spray tower. The first air inlet pipe passes through the water tank and is rotatably connected to the water tank. The drainage pipe passes through the side wall of the water tank and the heat exchange spray tower. One end of the drainage pipe is connected to the water tank, and the other end of the drainage pipe is connected to the heat exchange spray tower.

[0011] Based on the above solution, a cleaning mechanism is also included. The cleaning mechanism is installed on the first air intake pipe and is used to clean the filter cartridge. The cleaning mechanism includes a cleaning plate and a cleaning block. Multiple cleaning plates are arranged around the first air intake pipe. The sidewalls of the cleaning plates are evenly distributed with cleaning bristles. The cleaning bristles are in contact with the filter cartridge. The cleaning block is fixedly installed between the cleaning plate and the first air intake pipe.

[0012] Based on the above scheme, a water outlet pipe is installed through the side wall of the heat exchange spray tower.

[0013] Based on the above scheme, the end of the drain pipe that extends into the water tank has its opening facing downwards.

[0014] The beneficial effects of the embodiments of the present invention are as follows: 1. In this invention, by setting up a spraying mechanism, heat exchange liquid is injected into the first housing and spray pipe through the water inlet pipe. The heat exchange liquid can be sprayed into the heat exchange spraying tower through the nozzle. At the same time, the operation of the first motor can drive the first gear to rotate. The meshing of the first gear and the first gear ring drives the drive column and the second bevel gear to rotate. In turn, the meshing of the second bevel gear and the first bevel gear drives the first bevel gear and the spray pipe to rotate. This makes it easy to adjust the angle of the nozzle and achieve uniform and comprehensive spraying of the heat exchange liquid in the heat exchange spraying tower. 2. In this invention, by setting up an air intake mechanism, flue gas can be introduced into the first air intake pipe and the second air intake pipe through the air intake hose, and then the flue gas is introduced into the heat exchange spray tower through the air intake hole. At the same time, the rotation of the drive column can drive the first air intake pipe to rotate, thereby facilitating the adjustment of the position of the second air intake pipe and the air intake hole, thereby improving the uniformity of flue gas intake and improving the heat exchange efficiency. 3. In this invention, through the setting of the filter cylinder and the installation mechanism, the heat exchange liquid after heat exchange can enter the filter cylinder through the drain pipe, and after being filtered by the filter cylinder, the heat exchange liquid can be discharged through the outlet pipe, so that the heated heat exchange liquid can be introduced into the heat-using equipment for waste heat utilization. 4. In this invention, by setting up a cleaning mechanism, after heat exchange is completed, the rotation of the first air inlet pipe can drive the cleaning plate to move around the first air inlet pipe, thereby facilitating the cleaning of the filter cartridge by the cleaning bristles, thereby improving the subsequent filtration effect of the filter cartridge. Moreover, by rotating the mounting plate, the mounting plate can also be disassembled and installed, thereby facilitating the replacement of the filter cartridge. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are merely some exemplary embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the exemplary embodiments of the present invention and these drawings without any creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of a waste heat recovery device for flue gas from a gas-fired boiler in one embodiment of the present invention; Figure 2 This is a cross-sectional schematic diagram of a heat exchange spray tower according to one embodiment of the present invention; Figure 3 This is a cross-sectional structural diagram of the spraying mechanism in one embodiment of the present invention; Figure 4 For the present invention Figure 3 A magnified schematic diagram of the partial structure at point A in the middle; Figure 5 This is a schematic diagram of the structure of the air intake mechanism in one embodiment of the present invention; Figure 6 This is a cross-sectional view of the air intake mechanism in one embodiment of the present invention; Figure 7 This is a schematic diagram of the installation disc and filter cartridge in a mating state according to one embodiment of the present invention; In the diagram: 1. Heat exchange spray tower; 2. Support leg; 3. Fixing plate; 4. Vent; 5. First shell; 6. Water inlet pipe; 7. Water outlet pipe; 8. Second shell; 9. Spray pipe; 10. Spray head; 11. First bevel gear; 12. Second bevel gear; 13. First cavity; 14. Drive column; 15. First gear ring; 16. First gear; 17. First motor; 18. First air inlet pipe; 19. Second air inlet pipe; 20. Air inlet hole; 21. Air inlet hose; 22. Rotary joint; 23. Positioning ring; 24. Filter cylinder; 25. Water tank; 26. Drain pipe; 27. Cleaning plate; 28. Cleaning block; 29. ​​Mounting plate; 30. Positioning plate. Detailed Implementation The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it.

[0017] To keep the drawings concise, each drawing only schematically shows the parts relevant to the invention; these do not represent the actual structure of the product. Furthermore, for ease of understanding, in some drawings, only one of components with the same structure or function is schematically shown, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one," and "several" includes "two" and "more than two."

[0018] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0019] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0020] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of description and simplification of operation, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0021] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0022] like Figures 1-7 As shown, this invention illustrates a waste heat recovery device for flue gas from a gas-fired boiler, comprising a heat exchange spray tower 1. Multiple support legs 2 are fixedly mounted at the bottom of the heat exchange spray tower 1. The device also includes a fixed plate 3, a spraying mechanism, an air inlet mechanism, a positioning ring 23, a filter cartridge 24, an installation mechanism, and a drainage mechanism. The fixed plate 3 is fixedly mounted inside the heat exchange spray tower 1, and multiple air vents 4 are provided on the fixed plate 3. The spraying mechanism is mounted on the fixed plate 3 and is used to spray heat exchange liquid into the heat exchange spray tower 1. The boiler flue gas is heat-exchanged through the heat exchange liquid. The air inlet mechanism is set inside the heat exchange spray tower 1 to introduce the boiler flue gas into the heat exchange spray tower 1. The positioning ring 23 is fixedly set on the inner wall of the heat exchange spray tower 1. The filter cylinder 24 is set inside the heat exchange spray tower 1. The installation mechanism is set inside the heat exchange spray tower 1 to install and fix the filter cylinder 24. The water discharge mechanism is set inside the heat exchange spray tower 1 to introduce the heat exchange liquid after heat exchange into the filter cylinder 24. The water outlet pipe 7 is installed through the side wall of the heat exchange spray tower 1.

[0023] Reference Figures 1-6The spraying mechanism includes a first housing 5, a water inlet pipe 6, a second housing 8, spray pipes 9, nozzles 10, and a first rotating mechanism. The bottom end of the fixed disk 3 is fixedly provided with an annular first housing 5. The water inlet pipe 6 passes through the side wall of the heat exchange spray tower 1 and communicates with the first housing 5. The second housing 8 is fixedly provided on the bottom side wall of the fixed disk 3. Multiple spray pipes 9 are rotatably arranged between the second housing 8 and the inner wall of the first housing 5. One end of each spray pipe 9 communicates with the first housing 5, and the other end of each spray pipe 9 is sealed and extends into the second housing 8. The side wall of each spray pipe 9 is connected to a... Multiple nozzles 10 are provided. A first rotating mechanism is mounted on the second housing 8 to drive the spray pipe 9 to rotate. The first rotating mechanism includes a first bevel gear 11, a second bevel gear 12, and a drive mechanism. The first bevel gear 11 is fixedly mounted on the end of the spray pipe 9 away from the first housing 5. The second bevel gear 12 is rotatably mounted on the inner top wall of the second housing 8 and meshes with the first bevel gear 11. The drive mechanism is mounted on the fixed disk 3 to drive the second bevel gear 12 to rotate. The drive mechanism includes a first cavity 13, a drive column 14, a first gear ring 15, a first gear 16, and a first motor 17. The first cavity 13 is located within the fixed disk 3. A drive column 14 is fixedly mounted on the second bevel gear 12. Both ends of the drive column 14 extend out of the second housing 8 and are rotatably and sealingly connected to the side walls of the second housing 8. The top end of the drive column 14 extends into the first cavity 13 and is rotatably connected to the inner top wall of the first cavity 13. A first gear ring 15 is fixedly mounted on the outer wall of the drive column 14. A first gear 16 is rotatably mounted within the first cavity 13 and meshes with the first gear ring 15. A first motor 17 is mounted on the fixed disk 3, and the output end of the first motor 17 is fixedly connected to the first gear 16. Specifically, the operator... The heat exchange liquid can be pumped into the first housing 5 and the spray pipe 9 through the water inlet pipe 6, and sprayed into the heat exchange spray tower 1 through the nozzle 10. At the same time, the operation of the first motor 17 can drive the first gear 16 to rotate. The meshing of the first gear 16 with the first gear ring 15 drives the drive column 14 and the second bevel gear 12 to rotate. In turn, the meshing of the second bevel gear 12 with the first bevel gear 11 drives the first bevel gear 11 and the spray pipe 9 to rotate. This makes it easy to adjust the angle of the nozzle 10 and achieve uniform and comprehensive spraying of the heat exchange liquid in the heat exchange spray tower 1.

[0024] Reference Figures 2-6The air intake mechanism includes a first air intake pipe 18, a second air intake pipe 19, and an air intake hose 21. The first air intake pipe 18 is fixedly installed at the bottom end of the drive column 14, and both ends of the first air intake pipe 18 are sealed. Multiple second air intake pipes 19 are fixedly installed and connected to the side wall of the first air intake pipe 18. Multiple air intake holes 20 are opened on the bottom side wall of the second air intake pipe 19. A rotary joint 22 is connected to the bottom end of the first air intake pipe 18. The air intake hose 21 is installed at the end of the rotary joint 22 away from the first air intake pipe 18. The end of the air hose 21 away from the rotary joint 22 extends out of the heat exchange spray tower 1. Specifically, flue gas can be introduced into the first air inlet pipe 18 and the second air inlet pipe 19 through the air inlet hose 21, and then the flue gas is introduced into the heat exchange spray tower 1 through the air inlet hole 20. At the same time, the rotation of the drive column 14 can drive the first air inlet pipe 18 to rotate, thereby facilitating the adjustment of the position of the second air inlet pipe 19 and the air inlet hole 20, thereby improving the uniformity of flue gas intake and improving heat exchange efficiency.

[0025] Reference Figure 2 , Figure 3 and Figure 7 The installation mechanism includes an installation port, an installation plate 29, and a positioning plate 30. The installation port is located on the inner bottom wall of the heat exchange spray tower 1, and the inner wall of the installation port has internal threads. The outer wall of the installation plate 29 has external threads, and the installation plate 29 extends into the installation port through threaded engagement. The positioning plate 30 is fixedly mounted on the top side wall of the installation plate 29. The two ends of the filter cylinder 24 contact the positioning ring 23 and the installation plate 29, respectively. The air inlet hose 21 passes through the positioning plate 30 and the installation plate 29. The drainage mechanism includes a water tank 25 and a drain pipe 26. A water tank 25 is fixedly installed inside the heat exchange spray tower 1. The first air inlet pipe 18 passes through the water tank 25 and is rotatably connected to the water tank 25. The drain pipe 26 passes through the water tank 25 and the side wall of the heat exchange spray tower 1. One end of the drain pipe 26 is connected to the water tank 25, and the other end of the drain pipe 26 is connected to the heat exchange spray tower 1. Specifically, the heat exchange liquid after heat exchange can enter the filter cylinder 24 through the drain pipe 26. After being filtered by the filter cylinder 24, the heat exchange liquid can be discharged through the water outlet pipe 7, so that the heated heat exchange liquid can be introduced into the heat-using equipment for waste heat utilization.

[0026] Reference Figures 2-6The cleaning mechanism includes cleaning plates 27 and cleaning blocks 28. Multiple cleaning plates 27 are arranged around the first air inlet pipe 18. The side walls of the cleaning plates 27 are evenly distributed with cleaning bristles, which contact the filter cartridge 24. The cleaning blocks 28 are fixedly arranged between the cleaning plates 27 and the first air inlet pipe 18. Specifically, after heat exchange is completed, the rotation of the first air inlet pipe 18 can drive the cleaning plates 27 to move around the first air inlet pipe 18, thereby facilitating the cleaning of the filter cartridge 24 by the cleaning bristles, thereby improving the subsequent filtration effect of the filter cartridge 24. Moreover, the installation plate 29 can be disassembled and installed by rotating the installation plate 29, thereby facilitating the replacement of the filter cartridge 24.

[0027] In this embodiment, during use, the operator can inject heat exchange liquid into the first housing 5 and spray pipe 9 through the water inlet pipe 6, and spray the heat exchange liquid into the heat exchange spray tower 1 through the nozzle 10. Simultaneously, the operation of the first motor 17 drives the first gear 16 to rotate. The meshing of the first gear 16 with the first gear ring 15 drives the drive column 14 and the second bevel gear 12 to rotate. Furthermore, the meshing of the second bevel gear 12 with the first bevel gear 11 drives the first bevel gear 11 and the spray pipe 9 to rotate, thus facilitating the adjustment of the nozzle 10 angle and achieving uniform and comprehensive spraying of the heat exchange liquid into the heat exchange spray tower 1. Simultaneously, the operator can introduce flue gas into the first air inlet pipe 18 and the second air inlet pipe 19 through the air inlet hose 21, and then inject the flue gas into the heat exchange spray tower 1 through the air inlet hole 20. The rotation of the drive column 14 can also rotate the first air inlet pipe 18, thereby facilitating the adjustment of the position of the second air inlet pipe 19 and the air inlet hole 20, which can improve the uniformity of flue gas intake and the heat exchange efficiency. The heat exchange liquid after heat exchange can enter the filter cartridge 24 through the drain pipe 26, and after being filtered by the filter cartridge 24, it can be discharged through the outlet pipe 7, so that the heated heat exchange liquid can be passed into the heat-using equipment for waste heat utilization. After the heat exchange is completed, the rotation of the first air inlet pipe 18 can drive the cleaning plate 27 to move around the first air inlet pipe 18, which can facilitate the cleaning of the filter cartridge 24 by the cleaning bristles, thereby improving the subsequent filtration effect of the filter cartridge 24. Moreover, the installation plate 29 can be disassembled and installed by rotating it, which can facilitate the replacement of the filter cartridge 24.

[0028] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention 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 solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A waste heat recovery device for flue gas from a gas-fired boiler, comprising a heat exchange spray tower (1), wherein a plurality of support legs (2) are fixedly provided at the bottom end of the heat exchange spray tower (1), characterized in that, Also includes: Fixed plate (3), the fixed plate (3) is fixedly installed inside the heat exchange spray tower (1), and multiple air vents (4) are opened on the fixed plate (3); The spraying mechanism is set on the fixed plate (3) and is used to spray heat exchange liquid into the heat exchange spraying tower (1) and exchange heat with boiler flue gas through the heat exchange liquid. An air intake mechanism is provided inside the heat exchange spray tower (1) for introducing boiler flue gas into the heat exchange spray tower (1); Positioning ring (23), the positioning ring (23) is fixedly installed on the inner wall of the heat exchange spray tower (1); A filter cartridge (24) is disposed inside the heat exchange spray tower (1); The installation mechanism is located inside the heat exchange spray tower (1) and is used to install and fix the filter cylinder (24); The drainage mechanism is installed inside the heat exchange spray tower (1) and is used to pass the heat exchange liquid after heat exchange into the filter cylinder (24).

2. The waste heat recovery device for flue gas from a gas-fired boiler according to claim 1, characterized in that, The spraying mechanism includes: The first housing (5) is fixedly provided at the bottom end of the fixed disk (3). Water inlet pipe (6) is installed through the side wall of the heat exchange spray tower (1) and is connected to the first shell (5). The second housing (8) is fixedly disposed on the bottom side wall of the fixed disk (3); Spray pipe (9), a plurality of spray pipes (9) are rotatably disposed between the inner wall of the second housing (8) and the first housing (5). One end of the spray pipe (9) is connected to the first housing (5), and the other end of the spray pipe (9) is sealed and extends into the second housing (8). Spray nozzle (10), and multiple spray nozzles (10) are connected to the side wall of the spray pipe (9). A first rotating mechanism is disposed on the second housing (8) and is used to drive the spray pipe (9) to rotate.

3. The waste heat recovery device for flue gas from a gas-fired boiler according to claim 2, characterized in that, The first rotating mechanism includes: The first bevel gear (11) is fixedly provided at one end of the spray pipe (9) away from the first housing (5). The second bevel gear (12) is rotatably mounted on the inner top wall of the second housing (8), and the second bevel gear (12) meshes with the first bevel gear (11); A drive mechanism is provided on the fixed disk (3) for driving the second bevel gear (12) to rotate.

4. The waste heat recovery device for flue gas from a gas-fired boiler according to claim 3, characterized in that, The drive mechanism includes: The first cavity (13) is formed inside the fixed plate (3); The drive column (14) is fixedly mounted on the second bevel gear (12). Both ends of the drive column (14) extend out of the second housing (8) and are rotatably and sealingly connected to the side wall of the second housing (8). The top end of the drive column (14) extends into the first cavity (13) and is rotatably connected to the inner top wall of the first cavity (13). The first toothed ring (15) is fixedly disposed on the outer wall of the drive column (14); The first gear (16) is rotatably disposed in the first cavity (13) and meshes with the first gear ring (15); The first motor (17) is mounted on the fixed disk (3), and the output end of the first motor (17) is fixedly connected to the first gear (16).

5. The waste heat recovery device for flue gas from a gas-fired boiler according to claim 4, characterized in that, The air intake mechanism includes: The first air intake pipe (18) is fixedly installed at the bottom end of the drive column (14), and both ends of the first air intake pipe (18) are sealed. The second air intake pipe (19) is connected to and fixedly provided with multiple second air intake pipes (19) on the side wall of the first air intake pipe (18), and multiple air intake holes (20) are opened on the bottom side wall of the second air intake pipe (19). An air inlet hose (21) is provided with a rotary joint (22) at the bottom end of the first air inlet pipe (18). The air inlet hose (21) is installed at the end of the rotary joint (22) away from the first air inlet pipe (18). The end of the air inlet hose (21) away from the rotary joint (22) extends out of the heat exchange spray tower (1).

6. The waste heat recovery device for flue gas from a gas-fired boiler according to claim 5, characterized in that, The installation mechanism includes: The installation port is located on the inner bottom wall of the heat exchange spray tower (1), and the inner wall of the installation port is provided with internal threads. Mounting disc (29), the outer wall of which is provided with external threads, the mounting disc (29) extends into the mounting port through thread engagement; Positioning disk (30), the positioning disk (30) is fixedly disposed on the top side wall of the mounting disk (29); The filter cartridge (24) has two ends in contact with the positioning ring (23) and the mounting plate (29) respectively, and the air intake hose (21) passes through the positioning plate (30) and the mounting plate (29).

7. The waste heat recovery device for flue gas from a gas-fired boiler according to claim 6, characterized in that, The drainage system includes: Water tank (25), the water tank (25) is fixedly installed in the heat exchange spray tower (1), the first air inlet pipe (18) passes through the water tank (25) and is rotatably connected to the water tank (25); The drain pipe (26) is installed through the side wall of the water tank (25) and the heat exchange spray tower (1). One end of the drain pipe (26) is connected to the water tank (25), and the other end of the drain pipe (26) is connected to the heat exchange spray tower (1).

8. The waste heat recovery device for flue gas from a gas-fired boiler according to claim 7, characterized in that, It also includes a cleaning mechanism, which is disposed on the first air inlet pipe (18) and is used to clean the filter cartridge (24). The cleaning mechanism includes: Cleaning plate (27), a plurality of cleaning plates (27) are provided around the first air inlet pipe (18), and the sidewalls of the cleaning plates (27) are evenly distributed with cleaning bristles, which are in contact with the filter cartridge (24). A cleaning block (28) is fixedly disposed between the cleaning plate (27) and the first air intake pipe (18).

9. A waste heat recovery device for flue gas from a gas-fired boiler according to claim 8, characterized in that, A water outlet pipe (7) is installed through the side wall of the heat exchange spray tower (1).

10. A waste heat recovery device for flue gas from a gas-fired boiler according to claim 9, characterized in that, The end of the drain pipe (26) that extends into the water tank (25) has its opening facing downwards.

Images