A boiler tail heat recovery device based on eddy heat exchange

Abstract

The utility model discloses a kind of boiler tail heat recovery devices based on vortex heat exchange, it is related to waste heat recovery technical field, including vortex heat exchange main body, in the vortex heat exchange main body has high-temperature flue gas entrance, on the high-temperature flue gas entrance is equipped with the filter assembly for to the inside along it is filtered, the filter assembly includes filter box and the filter screen installed in its inside, the filter box has import and export, its import is communicated with boiler tail exhaust duct, its export is connected with throat pipe, the throat pipe is communicated with high-temperature flue gas entrance away from the one end of filter box, cleaning assembly for to the filter screen cleaning is arranged on the lateral wall of the filter box, and the cleaning assembly includes piston cylinder installed in its lateral wall.The utility model realizes the effect of on-line self-cleaning, without disassembling filter plate, guaranteeing device continuous operation, reduce the influence of shutdown on production efficiency.

Description

Technical Field

[0001] This utility model relates to the field of waste heat recovery technology, specifically a boiler tail heat recovery device based on eddy current heat exchange. Background Technology

[0002] In the industrial sector, boilers are widely used in power generation, chemical industry, and other industries. The high-temperature flue gas emitted from their tail ends contains a large amount of heat energy. Effectively recovering this heat energy can not only improve the boiler's energy utilization rate and reduce enterprise costs, but also reduce thermal pollution, which aligns with the needs of energy conservation, emission reduction, and green industrial development.

[0003] Against this backdrop, various boiler tail-end heat recovery devices have emerged, with those based on the eddy current heat transfer principle becoming a research and application hotspot due to their high heat transfer efficiency and compact structure. These devices use a heat exchanger as their core, enabling heat transfer between high-temperature flue gas and the medium to be heated, thus achieving heat energy recovery.

[0004] However, in actual operation, the flue gas at the tail end of the boiler contains impurities such as dust and fly ash. If these impurities enter the heat exchanger directly, they are likely to adhere to the surface of the heat exchange tubes or block the channels, resulting in a decrease in the heat transfer coefficient and a loss of heat recovery efficiency. This will also exacerbate the corrosion and wear of the heat exchange tubes, shorten the equipment life, and increase maintenance costs and failure risks.

[0005] To address this issue, existing technologies often incorporate filter plates at the heat exchanger inlet to filter impurities. However, these existing filter plates lack dedicated cleaning mechanisms, leading to a buildup of impurities on their surfaces after prolonged operation. This clogs the filter pores and increases resistance to flue gas flow. This not only reduces flue gas flow and degrades heat recovery efficiency but also increases the load on equipment such as induced draft fans and raises energy consumption due to excessive pressure differentials.

[0006] To ensure the performance of the filter plates and the normal operation of the heat exchanger, staff need to periodically stop the machine to disassemble, clean, or replace the filter plates. This process consumes manpower and resources, and frequent shutdowns interrupt the production process, reduce efficiency, and cause economic losses to the company.

[0007] In view of the above, this application is hereby submitted. Utility Model Content

[0008] The purpose of this invention is to provide a boiler tail heat recovery device based on eddy current heat exchange to solve the problems mentioned in the background art.

[0009] To solve the above-mentioned technical problems, this utility model provides a boiler tail heat recovery device based on eddy current heat exchange, including an eddy current heat exchange body. The eddy current heat exchange body has a high-temperature flue gas inlet. A filter assembly for filtering the flue gas entering the body is installed on the high-temperature flue gas inlet. The filter assembly includes a filter box and a filter screen installed inside it. The filter box has an inlet and an outlet. Its inlet is connected to the boiler tail exhaust pipe, and its outlet is connected to a throat pipe. The end of the throat pipe away from the filter box is connected to the high-temperature flue gas inlet. A cleaning assembly for cleaning the filter screen is provided on the side wall of the filter box. The cleaning assembly includes a piston cylinder installed on its side wall. A piston plate is slidably installed inside the piston cylinder. A piston rod is connected to one side of the piston plate. The end of the piston rod away from the piston plate extends into the filter box and is connected to a bottom surface that is in contact with the top surface of the filter screen. A drive assembly for driving the piston rod to slide back and forth is provided on the filter box.

[0010] Furthermore, the drive assembly includes a first connecting pipe and a second connecting pipe respectively connected to the throat section and the inlet section. The ends of the first connecting pipe and the second connecting pipe away from the throat section are respectively connected to the two ends of the piston cylinder. Changes in the flow rate of the flue gas discharged from the tail of the boiler will cause changes in the pressure difference between the inlet section and the throat section. This pressure difference is transmitted to both sides of the piston plate, causing the piston plate and piston rod to displace along the axis of the piston cylinder, thereby driving them to move along the surface of the filter screen.

[0011] Furthermore, a return spring is sleeved on the outside of the piston rod, one end of the return spring is connected to the piston plate, and the other end of the return spring is connected to the inner wall of the piston cylinder.

[0012] Furthermore, the side wall of the filter box has a connecting port that connects to the outside, and a dust collection box is installed on the side wall of the filter box, with the connecting port communicating with the inner cavity of the dust collection box.

[0013] Furthermore, a dust collection drawer is slidably inserted into the interior of the dust collection box, and the dust collection drawer is located below the communication port.

[0014] Furthermore, an opening is provided on the side wall of the filter box, and the piston rod extends into the interior of the filter box through the opening. A sealing ring is also installed inside the opening, and the inner wall of the sealing ring fits against the outer wall of the piston rod.

[0015] Furthermore, the eddy current heat exchanger body includes a tubular shell, which has a hollow tube structure and is connected to a front tube box and a rear tube box at both ends. Eddy current heat exchange tubes are installed inside the tubular shell. A water inlet and a water outlet are provided on the front tube box. The high-temperature flue gas inlet is located on the outer wall of the upper part of the tubular shell, and a low-temperature flue gas outlet is provided on the outer wall of the lower part of the tubular shell.

[0016] Compared with the prior art, the beneficial effects of this utility model are: This invention utilizes a throat pressure differential-driven cleaning component design. By leveraging the pressure difference between the throat inlet section and the throat section when the boiler flue gas flow changes, the pressure is transmitted via the first and second connecting pipes to the piston cylinder, driving the piston plate and piston rod to reciprocate. This, in turn, causes the cleaning component to scrape impurities along the top surface of the filter screen. The entire cleaning process requires no external power, relying entirely on the flue gas's own flow characteristics to achieve real-time self-cleaning. This avoids the problems of increased flue gas flow resistance and decreased heat exchange efficiency caused by filter screen blockage due to impurity accumulation. Furthermore, it eliminates the need for personnel to stop the machine and disassemble the filter screen, completely solving the core pain point of traditional equipment shutdown maintenance. This ensures continuous and stable heat exchange for the eddy current heat exchanger, improving overall heat recovery efficiency and production continuity. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the left-side structure of this utility model; Figure 2 This is a schematic diagram of the right-side structure of this utility model; Figure 3 This is a front view structural diagram of the present utility model; Figure 4 This is a cross-sectional structural diagram of the present invention.

[0018] In the diagram: 1. Tubular shell; 2. Front tube box; 3. Rear tube box; 4. Vortex heat exchange tube; 5. Water inlet; 6. Water outlet; 7. High-temperature flue gas inlet; 8. Low-temperature flue gas outlet; 9. Throat; 10. Filter box; 11. Filter screen; 12. Dust collection box; 13. Dust collection drawer; 14. Connecting port; 15. Piston cylinder; 16. First connecting pipe; 17. Second connecting pipe; 18. Piston plate; 19. Piston rod; 20. Return spring; 21. Cleaning scraper. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] Please see Figures 1-4This utility model provides a technical solution: a boiler tail heat recovery device based on eddy current heat exchange, comprising an eddy current heat exchange body, a high-temperature flue gas inlet 7, and a filter assembly installed on the high-temperature flue gas inlet 7 for filtering the gas entering and passing through it. The filter assembly includes a filter box 10 and a filter screen 11 installed inside it. The filter box 10 has an inlet and an outlet. Its inlet is connected to the boiler tail exhaust pipe, and its outlet is connected to a throat pipe 9. The end of the throat pipe 9 away from the filter box 10 is connected to the high-temperature flue gas inlet 10. The flue gas inlet 7 is connected, and a cleaning assembly for cleaning the filter screen 11 is provided on the side wall of the filter box 10. The cleaning assembly includes a piston cylinder 15 installed on its side wall. A piston plate 18 is slidably installed inside the piston cylinder 15. A piston rod 19 is connected to one side of the piston plate 18. The end of the piston rod 19 away from the piston plate 18 extends into the filter box 10 and is connected to a cleaning scraper 21. The bottom surface of the cleaning scraper 21 is in contact with the top surface of the filter screen 11. A drive assembly for driving the piston rod 19 to slide back and forth is provided on the filter box 10.

[0021] As a technical optimization of this utility model, the drive assembly includes a first connecting pipe 16 and a second connecting pipe 17 respectively connected to the throat section and the inlet section of the throat pipe 9. The ends of the first connecting pipe 16 and the second connecting pipe 17 away from the throat pipe 9 are respectively connected to the two ends of the piston cylinder 15. The change in the flow rate of the flue gas discharged from the tail of the boiler will cause the pressure difference between the inlet section and the throat section to change. This pressure difference is transmitted to both sides of the piston plate 18, causing the piston plate 18 and the piston rod 19 to move along the axis of the piston cylinder 15, thereby driving the cleaning scraper 21 to move along the upper surface of the filter screen 11.

[0022] Specifically, based on the vortex heat exchanger body, its high-temperature flue gas inlet 7 is connected to the filter box 10 through the throat pipe 9. The flue gas at the tail of the boiler first passes through the filter screen 11 in the filter box 10 to filter impurities, and then enters the vortex heat exchanger body for heat exchange. At the same time, a piston plate 18 is slidably installed in the piston cylinder 15 on the side wall of the filter box 10. The piston rod 19 on one side of the piston plate 18 extends into the filter box 10 and is connected to the cleaning scraper 21. The bottom surface of the cleaning scraper 21 is in contact with the top surface of the filter screen 11. The piston rod 19 is driven to slide back and forth through the drive assembly, so that the cleaning scraper 21 moves along the surface of the filter screen 11 to achieve cleaning.

[0023] As a technical optimization of this utility model, a return spring 20 is sleeved on the outside of the piston rod 19. One end of the return spring 20 is connected to the piston plate 18, and the other end of the return spring 20 is connected to the inner wall of the piston cylinder 15.

[0024] Specifically, because the flow cross-sections of the throat section and the inlet section of the throat pipe 9 are different, when the flue gas flow rate at the tail of the boiler changes, a pressure difference will be generated between the two sections. This pressure difference is transmitted to both sides of the piston plate 18, pushing the piston plate 18 and the piston rod 19 to move along the axis of the piston cylinder 15, and the return spring 20 plays a reset role.

[0025] As a technical optimization of this utility model, the side wall of the filter box 10 is provided with a connecting port 14 that connects to the outside, and a dust collection box 12 is installed on the side wall of the filter box 10, with the connecting port 14 communicating with the inner cavity of the dust collection box 12.

[0026] Specifically, the impurities scraped off by the cleaning scraper 21 from the filter screen 11 fall into the dust collection box 12 through the connecting port 14 and are collected.

[0027] As a technical optimization of this utility model, a dust collection drawer 13 is slidably inserted into the interior of the dust collection box 12, and the dust collection drawer 13 is located below the connecting port 14.

[0028] Specifically, after the impurities fall into the dust collection drawer 13 through the connecting port 14, the staff can directly pull out the dust collection drawer 13 to empty the impurities without disassembling the dust collection box 12.

[0029] As a technical optimization of this utility model, a through-hole is provided on the side wall of the filter box 10, and the piston rod 19 extends into the interior of the filter box 10 through the through-hole. A sealing ring is also installed inside the through-hole, and the inner wall of the sealing ring fits against the outer wall of the piston rod 19.

[0030] Specifically, when the piston rod 19 slides back and forth along the opening, the sealing ring always fits tightly against the outer wall of the piston rod 19 to prevent the high-temperature flue gas in the filter box 10 from leaking out from the gap between the opening and the piston rod 19.

[0031] As a technical optimization of this utility model, the eddy current heat exchanger body includes a tubular shell 1, which has a hollow tube structure. Its two ends are respectively connected to the front tube box 2 and the rear tube box 3. The inside of the tubular shell 1 is provided with eddy current heat exchange tubes 4. The front tube box 2 is provided with an inlet 5 and an outlet 6. The high temperature flue gas inlet 7 is provided on the outer wall of the upper part of the tubular shell 1, and the low temperature flue gas outlet 8 is provided on the outer wall of the lower part of the tubular shell 1.

[0032] Specifically, the tubular shell 1 has a hollow tube structure, with the front tube box 2 and the rear tube box 3 connected at both ends, and vortex heat exchange tubes 4 are installed inside; the medium to be heated enters the front tube box 2 from the inlet 5, flows through the vortex heat exchange tubes 4, and performs vortex heat exchange with the high-temperature flue gas entering from the high-temperature flue gas inlet 7 inside the tubular shell 1. After heat exchange, the medium is discharged from the outlet 6, and the low-temperature flue gas is discharged from the low-temperature flue gas outlet 8.

[0033] The device is centered around a vortex heat exchanger, which includes a tubular shell 1. The tubular shell 1 is connected to a front tube box 2 and a rear tube box 3 at both ends. It contains vortex heat exchange tubes 4. The inlet 5 and outlet 6 of the front tube box 2 are used for the inlet and outlet of the medium to be heated, such as cold water. The high-temperature flue gas inlet 7 at the top of the tubular shell 1 receives filtered high-temperature flue gas, and the low-temperature flue gas outlet 8 at the bottom discharges the heat-exchanged low-temperature flue gas. Simultaneously, the high-temperature flue gas inlet 7 is connected to the filter box 10 of the filter assembly via a throat pipe 9. The filter screen 11 inside the filter box 10 is responsible for pre-treating impurities in the flue gas. Cleaning and driving components on the side walls solve the problem of filter screen clogging. The dust collection box 12 at the bottom and the internal dust collection drawer 13 are used to collect impurities generated during cleaning.

[0034] Specific workflow: The high-temperature flue gas discharged from the tail end of the boiler first enters the inlet of the filter box 10 through the pipeline. After being filtered by the internal filter screen 11, impurities such as dust and fly ash in the flue gas are removed. The filtered flue gas enters the throat pipe 9 from the outlet of the filter box 10 and is transported along the throat pipe 9 to the high-temperature flue gas inlet 7 of the tubular shell 1, and finally enters the interior of the vortex heat exchanger body.

[0035] eddy current heat transfer stage The medium to be heated enters from the rear tube box 3 and flows through the vortex heat exchange tube 4 inside the tubular shell 1. The high-temperature flue gas entering the tubular shell 1 comes into contact with the outer wall of the vortex heat exchange tube 4. Through the vortex heat exchange principle, the high-temperature flue gas and the medium inside the tube are transferred. After the flue gas releases heat energy, its temperature decreases and it is discharged from the low-temperature flue gas outlet 8 at the bottom of the tubular shell 1. After the medium inside the tube absorbs heat, its temperature increases and it flows along the vortex heat exchange tube 4 to the front tube box 2, and finally is discharged from the outlet 6, completing the waste heat recovery.

[0036] Filter 11 Self-cleaning stage The clean power comes from the pressure difference change in the throat pipe 9: there is a difference in the flow cross section between the throat section and the inlet section of the throat pipe 9. When the flue gas discharge flow rate at the tail end of the boiler changes, the pressure difference between the two sections will change accordingly. This pressure difference is transmitted to both ends of the piston cylinder 15 through the first connecting pipe 16 and the second connecting pipe 17, and acts on the piston plate 18 inside the piston cylinder 15, pushing the piston plate 18 to slide back and forth along the axis of the piston cylinder 15.

[0037] The piston plate 18 drives the piston rod 19 to reciprocate synchronously. The cleaning scraper 21 connected to one end of the piston rod 19 that extends into the filter box 10 will move along the top surface of the filter screen 11 with the piston rod 19 to scrape off the impurities accumulated on the filter screen 11.

[0038] The scraped impurities fall through the connecting port 14 on the side wall of the filter box 10 into the dust collection drawer 13 of the dust collection box 12 below. The staff can periodically pull out the dust collection drawer 13 to clean the impurities without stopping the machine to disassemble the filter screen 11.

[0039] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0040] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A boiler tail heat recovery device based on eddy current heat exchange, comprising an eddy current heat exchange body having a high-temperature flue gas inlet (7), wherein a filter assembly for filtering flue gas entering and passing through the high-temperature flue gas inlet (7) is installed on the high-temperature flue gas inlet (7), characterized in that: The filter assembly includes a filter box (10) and a filter screen (11) installed inside it. The filter box (10) has an inlet and an outlet. Its inlet is connected to the flue gas duct at the tail of the boiler, and its outlet is connected to a throat pipe (9). The end of the throat pipe (9) away from the filter box (10) is connected to the high-temperature flue gas inlet (7). A cleaning assembly for cleaning the filter screen (11) is provided on the side wall of the filter box (10). The cleaning assembly includes a piston cylinder (15) installed on its side wall. A piston plate (18) is slidably installed inside the piston cylinder (15). A piston rod (19) is connected to one side of the piston plate (18). The end of the piston rod (19) away from the piston plate (18) extends into the filter box (10) and is connected to a cleaning scraper (21). The bottom surface of the cleaning scraper (21) is in contact with the top surface of the filter screen (11). A driving assembly for driving the piston rod (19) to slide back and forth is provided on the filter box (10).

2. The boiler tail heat recovery device based on eddy current heat transfer as described in claim 1, characterized in that: The drive assembly includes a first connecting pipe (16) and a second connecting pipe (17) respectively connected to the throat section and the inlet section of the throat pipe (9). The ends of the first connecting pipe (16) and the second connecting pipe (17) away from the throat pipe (9) are respectively connected to the two ends of the piston cylinder (15). The change in the flow rate of the flue gas discharged from the tail of the boiler will cause the pressure difference between the inlet section and the throat section to change. This pressure difference is transmitted to both sides of the piston plate (18), causing the piston plate (18) and the piston rod (19) to move along the axis of the piston cylinder (15), thereby driving the cleaning scraper (21) to move along the upper surface of the filter screen (11).

3. A boiler tail-end heat recovery device based on eddy current heat transfer as described in claim 1, characterized in that: A return spring (20) is sleeved on the outside of the piston rod (19). One end of the return spring (20) is connected to the piston plate (18), and the other end of the return spring (20) is connected to the inner wall of the piston cylinder (15).

4. A boiler tail-end heat recovery device based on eddy current heat transfer as described in claim 1, characterized in that: The filter box (10) has a connecting port (14) on its side wall that connects to the outside. A dust collection box (12) is installed on the side wall of the filter box (10). The connecting port (14) is connected to the inner cavity of the dust collection box (12).

5. A boiler tail-end heat recovery device based on eddy current heat transfer as described in claim 4, characterized in that: The dust collection box (12) has a dust collection drawer (13) that is slidably inserted inside, and the dust collection drawer (13) is located below the communication port (14).

6. A boiler tail-end heat recovery device based on eddy current heat transfer as described in claim 1, characterized in that: The filter box (10) has an opening on its side wall. The piston rod (19) extends into the interior of the filter box (10) through the opening. A sealing ring is also installed inside the opening. The inner wall of the sealing ring is in contact with the outer wall of the piston rod (19).

7. A boiler tail-end heat recovery device based on eddy current heat transfer as described in claim 1, characterized in that: The eddy current heat exchanger body includes a tubular shell (1), which has a hollow tube structure and is connected to a front tube box (2) and a rear tube box (3) at both ends. The tubular shell (1) is equipped with eddy current heat exchange tubes (4). The front tube box (2) is equipped with an inlet (5) and an outlet (6). The high temperature flue gas inlet (7) is located on the outer wall of the upper part of the tubular shell (1), and the low temperature flue gas outlet (8) is located on the outer wall of the lower part of the tubular shell (1).

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