Anti-corrosion device for air pre-heater

Abstract

The invention discloses an air pre-heater anti-corrosion device, and relates to the technical field of air pre-heater anti-corrosion devices, the air pre-heater anti-corrosion device comprises a front tank, an air inlet pipe used for being connected with a boiler flue gas outlet end is fixed at the bottom of the side wall of one end of the front tank, and an air outlet pipe used for being connected with an air inlet end of an air pre-heater is fixed at the top of the side wall of the other end of the front tank; a bottom tank is fixed to the lower end of the front tank, a liquid discharging pipe is fixed to the bottom end of the bottom tank, and an electromagnetic valve is installed on the liquid discharging pipe. The filter part directly intercepts large-particle ash and unburned substances in flue gas, the primary purification effect is achieved, it is ensured that the flue gas entering the air pre-heater is cleaner, and the blocking risk of the air pre-heater is reduced; the long-time contact between the sulfuric acid liquid drops and the surface of the device is blocked through the filtering piece, so that the corrosion risk is reduced to the minimum; after SO3 in the high-temperature flue gas is condensed into sulfuric acid liquid drops on the surface of the filtering piece, the sulfuric acid liquid drops can be cleaned in time, and the air pre-heater is prevented from being corroded by the liquid drops.

Description

Technical Field

[0001] The present invention relates to the technical field of air preheater anti-corrosion devices, and specifically to an air preheater anti-corrosion device. Background Art

[0002] In industries such as thermal power generation, the air preheater (abbreviated as air preheater), as an important heat exchange device, its stable operation is crucial for improving the boiler efficiency. However, the air preheater often faces the severe challenge of low-temperature corrosion during operation. Especially, sulfur oxides (SO3) in the flue gas condense into sulfuric acid droplets under low-temperature conditions, causing serious corrosion to the equipment. At the same time, large particulate ash and unburned substances carried in the flue gas not only pollute the air preheater but also may cause blockage and wear to subsequent equipment.

[0003] However, traditional anti-corrosion devices mostly rely on coatings or simple baffle structures, which are difficult to effectively block the long-term contact between sulfuric acid droplets and the equipment surface, resulting in a relatively high corrosion risk.

[0004] Moreover, the existing devices lack an automatic cleaning mechanism, and large particulate ash and unburned substances are likely to deposit in the air preheater, requiring frequent manual cleaning, which increases the maintenance cost.

[0005] Based on this, an air preheater anti-corrosion device is now provided, which can eliminate the drawbacks of the existing devices. Summary of the Invention

[0006] The purpose of the present invention is to provide an air preheater anti-corrosion device to solve the problems in the background art.

[0007] To achieve the above purpose, the present invention provides the following technical solutions:

[0008] An air preheater anti-corrosion device includes a pre-chamber. One end of the side wall of the pre-chamber is fixedly provided with an intake pipe for connecting the flue gas outlet end of the boiler, and the other end of the side wall of the pre-chamber is fixedly provided with an outlet pipe for connecting the intake end of the air preheater. The lower end of the pre-chamber is fixedly provided with a bottom tank, and the bottom end of the bottom tank is fixedly provided with a drain pipe, and a solenoid valve is installed on the drain pipe.

[0009] A filter element for filtering the flue gas is arranged inside the pre-chamber, and a cleaning structure for cleaning the filter element and the inner walls of the pre-chamber and the bottom tank is arranged inside the pre-chamber and the bottom tank, and a driving structure for driving the cleaning structure is installed at the upper end of the pre-chamber.

[0010] Preferably, the driving structure includes a motor installed at the upper end of the pre-chamber. The output end of the motor is fixedly connected to a main gear, the main gear meshes with a driven gear, and the driven gear is connected to the cleaning structure.

[0011] Preferably, the cleaning structure includes a main pipe and a lower cleaning unit. The slave gear is fixed to the top of the outer side wall of the main pipe. The lower cleaning unit includes a lower fixing ring fixed to the bottom of the side wall of the main pipe. The lower fixing ring is connected to a lower scraping plate through a connecting rod, and the lower scraping plate is attached to the inner wall of the bottom tank.

[0012] Preferably, a closing block is fixed to the bottom end of the main pipe. An air flow channel is arranged in the main pipe. The main pipe is connected to the output end of the soot blower through a connecting pipe, and the main pipe is rotatably connected to the connecting pipe. An upper fixing ring is fixed to the outer side wall of the main pipe, and the upper fixing ring is located above the lower cleaning unit. Two limiting blocks are fixed to the upper end of the upper fixing ring. The two limiting blocks are symmetrically fixed to the outer side wall of the main pipe. A plurality of nozzles for cleaning the filter element are installed at a position on the side wall of the main pipe close to the limiting blocks.

[0013] Preferably, the filter element includes a conical filter plate, a lower ring and an upper ring. The upper ring is fixed to the upper end of the conical filter plate, and the outer wall of the upper ring is attached to the inner wall of the pre-chamber. The lower ring is fixed to the bottom end of the conical filter plate. Limiting ports slidably matched with the limiting blocks are symmetrically formed in the lower ring. Two connecting blocks are symmetrically fixed to the upper end of the lower ring. A sliding pipe is fixed to the upper ends of the two connecting blocks. The sliding pipe is sleeved on the outer wall of the main pipe and can slide along it. The sliding pipe corresponds to the nozzle, and the nozzle is located in the concave area of the conical filter plate.

[0014] Preferably, upper scraping plates are fixed to the bottom end of the upper ring at equal angles, and the upper scraping plates are attached to the inner wall of the pre-chamber.

[0015] Preferably, a main fixing ring is fixed to the inner wall of the pre-chamber. The main fixing ring is located above the upper ring. A plurality of balls are rotatably installed at the lower end of the main fixing ring. A plurality of ball holes are formed above the upper ring. Each ball corresponds to a ball hole.

[0016] Preferably, the upper scraping plate is made of stainless steel.

[0017] Preferably, the bottom tank is funnel-shaped, and its inner wall is provided with a V-shaped slope.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. The filter element of the present invention directly intercepts large particulate ash and unburned substances in the flue gas, plays a preliminary purification role, ensures that the flue gas entering the air preheater is cleaner, and reduces the risk of air preheater blockage; and blocks the long-term contact between sulfuric acid droplets and the surface of the device through the filter element, minimizing the corrosion risk; after SO3 in the flue gas condenses into sulfuric acid droplets on the surface of the filter element, it will be cleaned in time to avoid the corrosion of the air preheater caused by the droplets.

[0020] 2. The present invention realizes the efficient removal of flue gas condensate droplets and impurities through the cooperation of a driving structure, a cleaning structure and a filter element; the conical filter plate intercepts large particles and adheres to droplets, and the gear drives the main pipe to rotate to drive the lower scraper to remove the sediment in the bottom tank; when the filter holes are blocked and the air pressure rises, the filter element automatically moves upward to expose the nozzle, and the soot blower conveys air flow pulses to clean the filter holes; at the same time, when the upper end face of the upper ring contacts the lower end face of the main fixed ring, the upper scraper rotates with the main pipe to clean the impurities attached to the inner wall of the pre-tank; due to the setting of the ball and the ball hole, the filter element will vibrate up and down during rotation, which is conducive to shaking off some impurities, further promoting the cleaning of impurities on the filter element.

[0021] 3. The bottom tank of the present invention is funnel-shaped, and its inner wall is provided with a V-shaped slope. By setting the V-shaped slope, it can guide the impurities to flow more smoothly inside the bottom tank. Due to the inclination angle of the slope, the impurities will quickly flow along the slope to the liquid outlet pipe of the bottom tank under the action of gravity, reducing the residence time of the impurities in the bottom tank, thereby improving the efficiency of impurity treatment. The V-shaped slope inside the bottom tank also helps to balance the distribution of impurities in the bottom tank, reducing the center of gravity shift caused by the accumulation of impurities, thereby improving the overall stability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic structural diagram of the present invention.

[0023] Figure 2 is a schematic diagram of the internal structure of the present invention.

[0024] Figure 3 is a schematic structural diagram of the filter element of the present invention.

[0025] Figure 4 is a schematic structural diagram of the lower cleaning unit of the present invention.

[0026] Figure 5 is a schematic structural diagram of the lower ring, the limiting port, the connecting block and the sliding pipe of the present invention.

[0027] Figure 6 is the present invention Figure 2 schematic diagram of the structure at position A in

[0028] Annotation of reference numerals: 1. Pre - placed tank; 11. Intake pipe; 12. Exhaust pipe; 13. Bottom tank; 14. Drain pipe; 15. Solenoid valve; 2. Driving structure; 21. Motor; 22. Main gear; 23. Driven gear; 3. Cleaning structure; 31. Main pipe; 311. Connecting pipe; 312. Sprayer; 313. Sealing block; 32. Lower cleaning unit; 321. Lower fixing ring; 322. Connecting rod; 323. Lower scraper; 33. Upper fixing ring; 34. Limiting block; 4. Filter element; 41. Conical filter plate; 42. Lower ring; 43. Limiting port; 44. Connecting block; 45. Slide pipe; 46. Upper ring; 47. Ball hole; 48. Upper scraper; 5. Main fixed ring; 51. Ball. Detailed implementation manners

[0029] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the drawings and embodiments.

[0030] In one embodiment, as Figures 1-6 shown, an air pre - heater anti - corrosion device includes a pre - placed tank 1. At the bottom of one end side wall of the pre - placed tank 1, an intake pipe 11 for connecting the outlet end of the boiler flue gas is fixed. At the top of the other end side wall of the pre - placed tank 1, an exhaust pipe 12 for connecting the intake end of the air pre - heater is fixed. At the lower end of the pre - placed tank 1, a bottom tank 13 is fixed. At the bottom end of the bottom tank 13, a drain pipe 14 is fixed, and a solenoid valve 15 is installed on the drain pipe 14;

[0031] A filter element 4 for filtering flue gas is arranged inside the pre - placed tank 1. A cleaning structure 3 for cleaning the filter element 4 and the inner walls of the pre - placed tank 1 and the bottom tank 13 is arranged inside the pre - placed tank 1 and the bottom tank 13. A driving structure 2 for driving the cleaning structure 3 is installed at the upper end of the pre - placed tank 1.

[0032] In this embodiment, the high - temperature boiler flue gas enters the pre - placed tank 1 through the intake pipe 11, first contacts the internal filter element 4. The filter element 4 directly blocks large - particle ash and unburned substances. SO3 in the low - temperature flue gas condenses into sulfuric acid droplets on the surface of the filter element 4, adheres to the filter element 4 and the inner walls of the pre - placed tank 1 and the bottom tank 13. The driving structure 2 drives the cleaning structure 3 to clean the filter element 4 and the inner walls of the pre - placed tank 1 and the bottom tank 13. The droplets flow into the bottom tank 13 at the bottom of the pre - placed tank under the action of gravity, realizing gas - liquid separation. By blocking the long - time contact between the sulfuric acid droplets and the surface of the device, the corrosion risk is minimized, thus solving the problem of low - temperature corrosion of the air pre - heater.

[0033] In an alternative embodiment, the driving structure 2 includes a motor 21 installed at the upper end of the pre - placed tank 1. The output end of the motor 21 is fixedly connected to a main gear 22. The main gear 22 meshes with a driven gear 23, and the driven gear 23 is connected to the cleaning structure 3.

[0034] It should be noted that the motor 21 drives the main gear 22 to rotate, and the main gear 22 drives the driven gear 23 to rotate, so that the cleaning structure 3 starts to operate, and the cleaning structure 3 cleans the filter element 4 and the inner walls of the pre-chamber 1 and the bottom tank 13.

[0035] In an alternative embodiment, the cleaning structure 3 includes a main pipe 31 and a lower cleaning unit 32. The driven gear 23 is fixed to the top of the outer side wall of the main pipe 31. The lower cleaning unit 32 includes a lower fixing ring 321 fixed to the bottom of the side wall of the main pipe 31. The lower fixing ring 321 is connected to a lower scraper 323 through a connecting rod 322, and the lower scraper 323 is in contact with the inner wall of the bottom tank 13.

[0036] It should be noted that the driven gear 23 drives the main pipe 31 to rotate. Since the lower fixing ring 321 of the lower cleaning unit 32 is fixed to the main pipe 31, the fixing ring 321 and the connecting rod 322 and the lower scraper 323 connected thereto rotate with the main pipe 31. And because the lower scraper 323 is in contact with the inner wall of the bottom tank 13, the lower scraper 323 scrapes the impurities on the inner wall of the bottom tank 13, and the scraped impurities are discharged through the drain pipe 14.

[0037] In an alternative embodiment, a closing block 313 is fixed to the bottom end of the main pipe 31. An air flow channel is provided in the main pipe 31. The main pipe 31 is connected to the output end of the soot blower through a connecting pipe 311, and the main pipe 31 is rotatably connected to the connecting pipe 311. An upper fixing ring 33 is fixed to the outer side wall of the main pipe 31, and the upper fixing ring 33 is located above the lower cleaning unit 32. Two limiting blocks 34 are fixed to the upper end of the upper fixing ring 33. The two limiting blocks 34 are symmetrically fixed to the outer side wall of the main pipe 31. A plurality of nozzles 312 for cleaning the filter element 4 are installed at a position on the side wall of the main pipe 31 close to the limiting blocks 34.

[0038] It should be noted that the soot blower sends air flow into the air flow channel of the main pipe 31 through the connecting pipe 311, and the air flow is ejected through the nozzles 312, so as to clean the filter element 4.

[0039] In an alternative embodiment, the filter element 4 includes a conical filter plate 41, a lower ring 42 and an upper ring 46. The upper ring 46 is fixed to the upper end of the conical filter plate 41, and the outer wall of the upper ring 46 is in contact with the inner wall of the pre-chamber 1. The lower ring 42 is fixed to the bottom end of the conical filter plate 41. Limiting ports 43 slidably matched with the limiting blocks 34 are symmetrically formed in the lower ring 42. Two connecting blocks 44 are symmetrically fixed to the upper end of the lower ring 42. Two sliding pipes 45 are fixed to the upper ends of the two connecting blocks 44. The sliding pipes 45 are sleeved on the outer wall of the main pipe 31 and can slide along it. The sliding pipes 45 correspond to the nozzles 312, and the nozzles 312 are located in the concave area of the conical filter plate 41.

[0040] It should be noted that when the filter holes on the conical filter plate 41 are blocked by impurities, the flue gas enters the inner part of the pre-chamber 1 through the inlet pipe 11. Since the flue gas cannot pass through the filter element 4, the air pressure below the filter element 4 increases, and then the flue gas pushes the filter element 4 upward; when the filter element 4 moves upward a certain distance, the sliding pipe 45 cannot block the spray head 312, and the spray head 312 sprays out the air flow. The sprayed air flow cleans the filter holes of the conical filter plate 41; after the filter holes are cleaned, the flue gas can pass through the filter element 4, and the air pressure below the filter element 4 returns to normal. Under the action of gravity, the filter element 4 moves downward along the main pipe 31 and returns to its initial position, which is conducive to the reuse of the filter element 4 and improves the working efficiency; the spray head 312 is located in the concave area of the conical filter plate 41, which can ensure that the scouring air flow can directly act on the surface of the conical filter plate 41 and the concave part below it, ensuring that all parts of the conical filter plate 41 can be fully flushed and preventing local blockage or reduction of filtration efficiency caused by insufficient flushing.

[0041] In an alternative embodiment, the bottom end of the upper ring 46 is fixedly provided with upper scraping plates 48 at equal angles, and the upper scraping plates 48 are in contact with the inner wall of the pre-chamber 1.

[0042] It should be noted that as described in the above embodiment, the lower ring 42 is slidably engaged with the limit block 34 through the limit port 43, so that when the main pipe 31 rotates, the filter element 4 rotates accordingly, driving the upper ring 46 and the upper scraping plates 48 to rotate accordingly. During the rotation, the upper scraping plates 48 clean the impurities attached to the inner wall of the pre-chamber 1.

[0043] In an alternative embodiment, a main fixed ring 5 is fixed to the inner wall of the pre-chamber 1. The main fixed ring 5 is located above the upper ring 46. A number of rolling balls 51 are rotatably installed at the lower end of the main fixed ring 5, and a number of ball holes 47 are formed in the upper part of the upper ring 46, and each rolling ball 51 corresponds to a ball hole 47.

[0044] It should be noted that as described in the above embodiment, the filter element 4 rotates with the main pipe 31. When the filter holes of the conical filter plate 41 are blocked, the flue gas pushes the filter element 4 upward until the upper end surface of the upper ring 46 contacts the lower end surface of the main fixed ring 5. The upper scraping plates 48 rotate with the main pipe 31. Since the rolling balls 51 correspond to the ball holes 47, the upper scraping plates 48 also vibrate up and down during the rotation, which is conducive to shaking off some impurities and is conducive to cleaning the impurities on the filter element 4.

[0045] In an alternative embodiment, the upper scraping plates 48 are made of stainless steel.

[0046] It should be noted that stainless steel performs excellently in a high-temperature flue gas environment containing sulfates, can resist condensate corrosion, and ensure the long-term integrity of the scraping plates; it still maintains stable physical properties at high temperatures and adapts to the temperature fluctuations of the flue gas at the inlet of the air preheater.

[0047] In an optional embodiment, the bottom tank 13 is funnel-shaped, and its inner wall is provided with a V-shaped slope.

[0048] It should be noted that the impurities at the positions of the filter holes of the conical filter plate 41 and the impurities on the inner wall of the pre-tank 1 are scraped off and flow into the interior of the bottom tank 13. Since the bottom tank 13 is funnel-shaped and its inner wall is provided with a V-shaped slope, it is beneficial for the impurities to converge to the bottommost part of the inner cavity of the bottom tank 13, which is conducive to discharging through the drain pipe 14 later.

[0049] The above embodiment discloses an anti-corrosion device for an air preheater. Among them, the high-temperature flue gas generated by the boiler enters the interior of the pre-tank 1 through the inlet pipe 11 and first contacts the filter element 4. The filter element 4 is composed of a conical filter plate 41, a lower ring 42 and an upper ring 46. The conical filter plate 41 directly blocks the large-particle ash and unburned substances in the flue gas, playing a role of preliminary filtration. At the same time, SO3 in the low-temperature flue gas condenses into sulfuric acid droplets on the surface of the filter element 4, and these droplets will adhere to the inner walls of the filter element 4, the pre-tank 1 and the bottom tank 13.

[0050] The motor 21 drives the main gear 22 to rotate, and the main gear 22 drives the driven gear 23 to rotate, so that the cleaning structure 3 starts to operate. The driven gear 23 drives the main pipe 31 to rotate. The lower fixing ring 321 of the lower cleaning unit 32 is fixed to the main pipe 31. Therefore, the lower fixing ring 321 and the connecting rod 322 and the lower scraper 323 connected thereto rotate with the main pipe 31. The lower scraper 323 is in contact with the inner wall of the bottom tank 13 to scrape off the impurities on the inner wall of the bottom tank 13. At the same time, since the lower ring 42 is slidably matched with the limiting block 34 through the limiting port 43, when the main pipe 31 rotates, the filter element 4 rotates accordingly, driving the upper ring 46 and the upper scraper 48 to rotate accordingly. The upper scraper 48 is in contact with the inner wall of the pre-tank 1 to clean the impurities attached to the inner wall of the pre-tank 1 during rotation.

[0051] When the filter holes on the conical filter plate 41 are blocked by impurities, the flue gas cannot pass through the filter element 4, resulting in an increase in the air pressure below the filter element 4. The increased air pressure will push the filter element 4 to move upward along the main pipe 31. When the filter element 4 moves upward a certain distance, the nozzle 312 originally blocked by the sliding pipe 45 is exposed. At this time, the soot blower sends the air flow into the air flow channel of the main pipe 31 through the connecting pipe 311, and the air flow is ejected through the nozzle 312 and directly acts on the filter holes of the conical filter plate 41 to clean them. At the same time, when the upper end surface of the upper ring 46 contacts the lower end surface of the main fixed ring 5, the upper scraper 48 rotates with the main pipe 31, and the upper scraper 48 cleans the impurities attached to the inner wall of the pre-tank 1 during rotation. Since the ball 51 corresponds to the ball hole 47, the filter element 4 will vibrate up and down during rotation, which is beneficial to shaking off some impurities and further promoting the cleaning of the impurities on the filter element 4.

[0052] By blocking the long-term contact between the sulfuric acid droplets and the surface of the device, the corrosion risk is minimized, thus solving the problem of low-temperature corrosion of the air preheater.

[0053] After the filter holes are cleaned, the flue gas can pass through the filter element 4, the air pressure below the filter element 4 returns to normal, and the filter element 4 moves downward along the main pipe 31 under the action of gravity and returns to its initial position, realizing the reuse of the filter element 4.

[0054] During the whole working process, the device effectively removes the impurities and condensate droplets in the flue gas through steps such as filtration, cleaning and liquid drainage, prevents the corrosion of these substances to the air preheater, and protects the normal operation of the air preheater.

[0055] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An air preheater anti-corrosion device, characterized in that, It includes a pre - tank (1). At the bottom of one side wall of the pre - tank (1), an intake pipe (11) for connecting the outlet end of the boiler flue gas is fixed. At the top of the other side wall of the pre - tank (1), an outlet pipe (12) for connecting the intake end of the air pre - heater is fixed. The lower end of the pre - tank (1) is fixed with a bottom tank (13). The bottom end of the bottom tank (13) is fixed with a drain pipe (14), and a solenoid valve (15) is installed on the drain pipe (14). Inside the pre - tank (1), a filter element (4) for filtering flue gas is provided. Inside the pre - tank (1) and the bottom tank (13), a cleaning structure (3) for cleaning the filter element (4) and the inner walls of the pre - tank (1) and the bottom tank (13) is provided. At the upper end of the pre - tank (1), a driving structure (2) for driving the cleaning structure (3) is installed.

2. The anti-corrosion device for an air preheater according to claim 1, wherein The driving structure (2) includes a motor (21) installed at the upper end of the pre - tank (1). The output end of the motor (21) is fixedly connected to a main gear (22). The main gear (22) meshes with a driven gear (23), and the driven gear (23) is connected to the cleaning structure (3).

3. The anti-corrosion device for air preheater according to claim 2, wherein The cleaning structure (3) includes a main pipe (31) and a lower cleaning unit (32). The driven gear (23) is fixed at the top of the outer side wall of the main pipe (31). The lower cleaning unit (32) includes a lower fixing ring (321) fixed at the bottom of the side wall of the main pipe (31). The lower fixing ring (321) is connected to a lower scraping plate (323) through a connecting rod (322), and the lower scraping plate (323) is in contact with the inner wall of the bottom tank (13).

4. An air preheater anti-corrosion device according to claim 3, characterized in that, A closed block (313) is fixed at the bottom end of the main pipe (31). An air flow channel is provided inside the main pipe (31). The main pipe (31) is connected to the output end of the soot blower through a connecting pipe (311), and the main pipe (31) is rotatably connected to the connecting pipe (311). An upper fixing ring (33) is fixed on the outer side wall of the main pipe (31), and the upper fixing ring (33) is located above the lower cleaning unit (32). Two limiting blocks (34) are fixed at the upper end of the upper fixing ring (33). The two limiting blocks (34) are symmetrically fixed on the outer side wall of the main pipe (31). A number of spray nozzles (312) for cleaning the filter element (4) are installed at the position of the side wall of the main pipe (31) near the limiting blocks (34).

5. An air preheater anti-corrosion device according to claim 4, characterized in that, The filter element (4) includes a conical filter plate (41), a lower ring (42) and an upper ring (46). The upper ring (46) is fixed at the upper end of the conical filter plate (41), and the outer wall of the upper ring (46) is in contact with the inner wall of the pre - tank (1). The lower ring (42) is fixed at the bottom end of the conical filter plate (41). Limiting openings (43) which are slidably matched with the limiting blocks (34) are symmetrically arranged on the lower ring (42). Two connecting blocks (44) are symmetrically fixed at the upper end of the lower ring (42). Two sliding pipes (45) are fixed at the upper ends of the two connecting blocks (44). The sliding pipes (45) are sleeved on the outer wall of the main pipe (31) and can slide along it. The sliding pipes (45) correspond to the spray nozzles (312), and the spray nozzles (312) are located in the concave area of the conical filter plate (41).

6. The anti-corrosion device for air preheater according to claim 5, characterized in that, The bottom end of the upper ring (46) is fixedly provided with upper scraping plates (48) at equal angles, and the upper scraping plates (48) are attached to the inner wall of the pre-storage tank (1).

7. The anti-corrosion device for an air preheater according to claim 6, characterized in that, A main fixed ring (5) is fixed to the inner wall of the pre-storage tank (1). The main fixed ring (5) is located above the upper ring (46). A number of balls (51) are rotatably installed at the lower end of the main fixed ring (5). A number of ball holes (47) are formed above the upper ring (46), and each ball (51) corresponds to a ball hole (47).

8. The anti-corrosion device for an air preheater according to claim 6, characterized in that, The upper scraping plates (48) are made of stainless steel.

9. The anti-corrosion device for an air preheater according to claim 1, characterized in that, The bottom tank (13) is funnel-shaped, and its inner wall is provided with a V-shaped slope.

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