Anti-blocking device for boiler air preheater

Abstract

The invention relates to the technical field of anti-blocking of air preheaters, in particular to an anti-blocking device for a boiler air preheater, which comprises an air preheater and an air outlet hopper fixedly connected to the circumference of the bottom of the air preheater, and an air inlet hopper is fixedly connected to the top of the air preheater along the circumference. Preheating pipes are evenly and fixedly connected between the top and the bottom of the air preheater in a penetrating mode at intervals, a transverse plate is fixedly connected to the inner side of the air preheater, and the preheating pipes fixedly penetrate through the transverse plate. When flue gas is discharged into the preheating pipe, an electric heating wire is started, then an electric lead screw is started to rotate forwards and backwards alternately to drive an n-shaped plate to move up and down, the n-shaped plate drives a scraping plate to move up and down, and the scraping plate drives the electric heating wire to move up and down to heat the lower portion of the preheating pipe, so that the temperature of the preheating pipe is higher than the dew point of water vapor and acid gas in the flue gas; and meanwhile, dust attached to the outer wall of the preheating pipe is scraped away through a scraping plate, blockage caused by dust attached to the inner wall of the preheating pipe can be prevented through the heating effect of a spiral scraping plate and an electric heating wire, and therefore the smoke flowing efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of air preheater anti-blocking, and in particular to an anti-blocking device for a boiler air preheater. Background Art

[0002] The air preheater is an important boiler device, which is directly related to whether the boiler can really play its original role. Once the air preheater is blocked, the heat transfer of the boiler will be hindered in various ways, which will have a very adverse effect on the effectiveness of the boiler, so it is necessary to take corresponding measures to prevent the air preheater from blocking.

[0003] The Chinese patent with publication number CN109340813A discloses a vertical tubular air preheater anti-blocking device, including an anti-blocking box for installation at the air side inlet of the vertical tubular air preheater, the anti-blocking box including a first air inlet and a second air inlet, the first air inlet and the second air inlet are respectively provided with a first anti-blocking baffle and a second anti-blocking baffle, the first anti-blocking baffle and the second anti-blocking baffle are respectively connected to a first anti-blocking drive motor and a second anti-blocking drive motor, the first anti-blocking baffle is used to drive the first anti-blocking drive motor. The first air inlet is closed or opened, and the second anti-blocking baffle is used to close or open the second air inlet under the drive of the second anti-blocking drive motor. Although the above patent can control the flow rate of air entering and then heat the lower part of the preheating tube through the original heat of the flue gas, due to the downward flow of the flue gas, the temperature of the flue gas will continue to decrease with the flow, resulting in the lower part of the preheating tube still being difficult to heat up, resulting in the temperature of the lower part of the preheating tube being lower than the water vapor dew point and acid gas dew point in the flue gas, which is easily blocked and corroded by the formed ash, affecting the efficiency of the flue gas flow.

[0004] The present invention aims to solve the problems existing in the above patents. To this end, an anti-blocking device for a boiler air preheater is proposed, which can heat the lower part of the preheating tube and scrape off the dust attached to the outer wall to prevent blockage and improve the flue gas flow efficiency. Summary of the invention

[0005] In order to overcome the disadvantage that due to the downward flow of flue gas, the temperature of the flue gas will continue to decrease as the flue gas flows, resulting in the lower part of the preheating tube being still difficult to heat up, causing the temperature of the lower part of the preheating tube to be lower than the water vapor dew point and the acid gas dew point in the flue gas, and being easily blocked and corroded by the formed ash, thereby affecting the efficiency of the flue gas flow, the present invention provides an anti-blocking device for a boiler air preheater, which can heat the lower part of the preheating tube and scrape off the dust attached to the outer wall to prevent blockage and improve the flue gas flow efficiency.

[0006] The present invention is achieved through the following technical solutions:

[0007] A device for preventing blocking of a boiler air preheater comprises an air preheater and an air outlet hopper fixedly connected to the circumference of the bottom of the air preheater, an air inlet hopper fixedly connected to the top of the air preheater along the circumference, preheating pipes fixedly connected at even intervals between the top and the bottom of the air preheater, a transverse plate fixedly connected to the inside of the air preheater, the preheating pipes fixedly pass through the transverse plate, and also comprises a flow guide assembly, a guide rod, a scraper plate, an n-type plate, an electric lead screw, an electric heating wire and a scraper assembly. The air preheater is provided with a flow guide assembly for controlling the flow of air, the four corners of the bottom of the air preheater are fixedly connected to guide rods, and a slidable sleeve located under the transverse plate is provided between the guide rods. The scraper plate is square and is slidably mounted on the preheating tube. Electric heating wires are evenly spaced inside the scraper plate. An n-type plate is fixed on the scraper plate. The n-type plate slides through the partition. An electric screw threadedly connected to the n-type plate is installed on the top of the cross plate. The electric screw is used to drive the n-type plate to move up and down. The n-type plate drives the scraper plate to move up and down, so that the scraper plate moves up and down to heat the preheating tube to the required temperature through the electric heating wire. At the same time, the scraper plate can also scrape off the dust attached to the outer wall of the preheating tube. A scraper assembly is arranged between the electric screw and the preheating tube to scrape off the dust attached to the inner wall of the preheating tube.

[0008] To further explain, the guide assembly includes guide buckets symmetrically fixedly connected to both sides of the air preheater to guide the exhaust air, a heater is fixedly connected to the inner side of the guide bucket, a shell is fixedly connected between the guide bucket and the air preheater, a baffle is slidably connected to the shell, the baffle slides through the guide bucket to block the exhaust air, a partition is fixedly connected between the cross plate and the air preheater to divide the lower part of the air preheater into two parts, and a driving assembly is arranged between the shell and the baffle to drive the baffle to move.

[0009] To further explain, the drive assembly includes a drive motor installed on the air preheater, the output shaft of the drive motor passes through the shell and is fixedly connected to a spur gear, and the baffle is fixedly connected to an L-shaped rack meshing with the spur gear.

[0010] To further explain, the scraper assembly includes an annular plate rotatably connected to the top circumference of the preheating tube, a spiral scraper in contact with the inner wall of the preheating tube is fixed to the bottom of the annular plate for scraping off dust attached to the inner wall of the preheating tube, and a rotating assembly is arranged between the annular plate and the electric screw for driving the annular plate to rotate.

[0011] Further explanation, the rotating assembly includes a worm wheel fixed to the circumference of the outer side surface of the annular plate, and two groups of worm gears are symmetrically rotatably connected between the two sides of the air preheater. The number of worm gears in each group is two, and the two worm gears in each group are driven by a synchronous belt assembly. The worm gears are meshed with the worm wheel. A driving rod located between the worm gears is rotatably connected between the two sides of the air preheater, and the driving rod and the electric screw are driven by a bevel gear assembly, and the driving rod and the inner worm gear are driven by a synchronous belt assembly.

[0012] Further explanation, the anti-blocking device for the boiler air preheater also includes a filtering assembly, which includes an air collecting hopper fixedly connected to the inner side of the air outlet hopper to collect and guide the flue gas discharged from the preheating pipe. A vertical plate is fixedly connected between the air collecting hopper and the air outlet hopper to divide the inner side of the air outlet hopper into two cavities. Filter mesh plates are clamped on both sides of the air outlet hopper to filter dust in the flue gas. A switching assembly is arranged between the air collecting hopper and the vertical plate to switch the direction of the flue gas flow.

[0013] Further explanation, the switching component includes a perforated ball fixedly connected between the air outlet end of the gas collecting hopper and the vertical plate, the holes of the perforated ball are on the left and right sides, and a slanted guide plate is rotatably connected between the middle part of the perforated ball and the vertical plate to switch the direction of smoke flow. A stepper motor is installed on the gas collecting hopper, and the output shaft end of the stepper motor is fixedly connected to the shaft of the guide plate.

[0014] As a further explanation, the anti-blocking device for the boiler air preheater also includes a filter plate installed at the end of the guide bucket for filtering impurities in the air.

[0015] The beneficial effects of the present invention are:

[0016] 1. Whenever the flue gas is discharged into the preheating tube, start the electric heating wire, and then start the electric screw to rotate alternately to drive the n-type plate to move up and down, the n-type plate drives the scraper plate to move up and down, and the scraper plate drives the electric heating wire to move up and down to heat the lower part of the preheating tube, so that the temperature of the preheating tube is higher than the dew point of water vapor and acid gas in the flue gas. At the same time, the scraper plate also scrapes off the dust attached to the outer wall of the preheating tube. The heating effect of the spiral scraper and the electric heating wire can prevent the dust from adhering to the inner wall of the preheating tube and causing blockage, thereby improving the efficiency of flue gas flow.

[0017] 2. Under the action of the filter plate, whenever the smoke is discharged into the air outlet hopper through the guide plate, the filter plate can filter the dust in the smoke, and the smoke after dust filtering continues to be discharged for subsequent use. In this way, a large amount of dust in the smoke can be prevented from affecting subsequent use, thereby ensuring the effect of subsequent use of the smoke.

[0018] 3. Under the action of the filter plate, whenever the air is discharged into the right guide bucket, the filter plate can first filter part of the dust in the air, and the air after filtering part of the dust continues to be discharged into the air preheater, which can prevent the dust in the air from adhering to the outer wall of the preheating tube and affecting the heat exchange, thereby ensuring the effect of heat exchange between air and flue gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0020] Figure 2It is a three-dimensional structural schematic diagram of the preheating tube, guide bucket and heater of the present invention.

[0021] Figure 3 It is a schematic diagram of the three-dimensional structure of the partition and the baffle of the present invention.

[0022] Figure 4 It is a three-dimensional structural schematic diagram of the scraper plate and the electric screw rod of the present invention.

[0023] Figure 5 It is a schematic diagram of the three-dimensional structure of the scraper plate and the n-type plate of the present invention.

[0024] Figure 6 It is a schematic diagram of the three-dimensional structure of the heating wire of the present invention.

[0025] Figure 7 It is a schematic diagram of the three-dimensional structure of the scraper assembly of the present invention.

[0026] Figure 8 It is a schematic diagram of the three-dimensional structure of the spiral scraper of the present invention.

[0027] Fig. 9 It is a schematic diagram of the three-dimensional structure of the filter assembly of the present invention.

[0028] Fig.10 It is a schematic diagram of the three-dimensional structure of the perforated ball and the guide plate of the present invention.

[0029] Fig.11 It is a schematic diagram of the three-dimensional structure of the filter plate of the present invention.

[0030] Markings in the figure are: 1. air preheater, 2. air outlet hopper, 3. air inlet hopper, 4. preheating pipe, 5. horizontal plate, 6. guide hopper, 61. heater, 62. shell, 63. baffle, 64. partition, 65. drive motor, 66. spur gear, 67. L-shaped rack, 7. guide rod, 8. scraper plate, 9. n-type plate, 10. electric screw, 11. heating wire, 12. annular plate, 1201, spiral scraper, 121, drive rod, 122, worm, 123, worm wheel, 14, air collecting hopper, 141, vertical plate, 142, filter screen plate, 143, perforated ball, 144, guide plate, 145, stepper motor, 15, filter plate. DETAILED DESCRIPTION

[0031] First of all, it should be pointed out that in the different described embodiments, the same parts are provided with the same reference numerals or the same component names, wherein the disclosure contained in the entire description can be transferred to the same parts with the same reference numerals or the same component names. Selected positional descriptions in the description, such as top, bottom, lateral, etc., also refer to the directly described and shown figures and are transferred to the new positions in the case of a change in position.

[0032] Example: A blocking prevention device for a boiler air preheater, see Figure 1-Figure 8 As shown, it includes an air preheater 1 and an air outlet hopper 2 fixed to the circumference of the bottom of the air preheater 1, an air inlet hopper 3 fixed to the top of the air preheater 1 along the circumference, a preheating tube 4 is fixedly connected between the top and the bottom of the air preheater 1 at uniform intervals, a cross plate 5 is fixed to the middle of the inner side of the air preheater 1, and the preheating tube 4 is fixedly penetrated through the cross plate 5, and also includes a guide assembly, a guide rod 7, a scraper plate 8, an n-type plate 9, an electric screw 10, an electric heating wire 11 and a scraper assembly. The air preheater 1 is provided with a guide assembly. When the guide assembly is in operation, the guide assembly can realize the guide control of the air, the four corners of the bottom of the air preheater 1 are fixed with guide rods 7, and scraper plates 8 are slidably mounted between the four guide rods 7. The scraper plates 8 are located below the cross plate 5, and the scraper plates 8 are slidably mounted on the preheating tube 4, electric heating wires 11 are evenly spacedly installed on the inner side of the scraper plate 8, an n-type plate 9 is fixedly connected to the left side of the top of the scraper plate 8, and the n-type plate 9 slides through the left side of the partition 64, and an electric screw 10 is installed on the left side of the top of the cross plate 5, and the electric screw 10 is threadedly connected to the upper part of the n-type plate 9. The electric screw 10 is used to drive the n-type plate 9 to move up and down, and the n-type plate 9 drives the scraper plate 8 to move up and down, so that the scraper plate 8 moves up and down to heat the preheating tube 4 to the required temperature through the electric heating wire 11. At the same time, the scraper plate 8 can also scrape off the dust attached to the outer wall of the preheating tube 4 to ensure the heating effect of the preheating tube 4. A scraper assembly is arranged between the electric screw 10 and the preheating tube 4. When the scraper assembly is in operation, the scraper assembly can scrape off the dust attached to the inner wall of the preheating tube 4.

[0033] See also Figure 2 and Figure 3As shown, the guide assembly includes a guide bucket 6, a heater 61, a shell 62, a baffle 63, a partition 64 and a driving assembly. The lower parts of the left and right sides of the air preheater 1 are symmetrically fixed with guide buckets 6, and the guide buckets 6 can guide the discharged air. The inner side of the guide bucket 6 is fixed with a heater 61, and the shell 62 is fixed between the outer side surfaces of the guide buckets 6 on the front and rear sides and the left and right outer side surfaces of the air preheater 1. The sides of the left and right shells 62 that are away from each other are slidably connected with baffles 63. The right baffle 63 slides through the guide bucket 6 on the right rear side, and the left baffle 63 slides through the guide bucket 6 on the left front side. When the baffle 63 moves downward to block the inner side of the guide bucket 6, the baffle 63 can In order to block the discharged air, a partition 64 is fixedly connected between the right side of the bottom of the horizontal plate 5 and the right side of the bottom of the air preheater 1. The partition 64 can separate the lower part of the air preheater 1 into two parts. A driving component is arranged between the shell 62 and the baffle 63. When the driving component is in operation, the driving component can drive the baffle 63 to move up and down; the driving component includes a driving motor 65, a spur gear 66 and an L-shaped rack 67. The driving motor 65 is installed on the lower part of the left and right sides of the air preheater 1. The output shaft of the driving motor 65 passes through the shell 62 and is fixedly connected to the spur gear 66. The upper part of the left and right baffles 63 away from each other is fixedly connected to the L-shaped rack 67, and the L-shaped rack 67 is meshed with the spur gear 66.

[0034] See also Figure 7 and Figure 8 As shown, the scraper assembly includes an annular plate 12, a spiral scraper 1201 and a rotating assembly. The top of each preheating tube 4 is rotatably connected to the annular plate 12 along the circumferential direction. The bottom of the annular plate 12 is fixedly connected to the spiral scraper 1201. The spiral scraper 1201 contacts the inner wall of the preheating tube 4. When the spiral scraper 1201 rotates, the spiral scraper 1201 can scrape the dust attached to the inner wall of the preheating tube 4. A rotating assembly is arranged between the annular plate 12 and the electric screw 10. When the rotating assembly is in operation, the rotating assembly can drive the annular plate 12 to rotate; the rotating assembly includes a driving rod 121, a worm 122 and a worm wheel 123. The annular plate A worm wheel 123 is fixedly connected to the outer side surface of 12 along the circumferential direction. Two groups of worm gears 122 are symmetrically rotatably connected between the upper parts of the left and right sides of the air preheater 1. The number of worm gears 122 in each group is two. The right sides of each group of two worm gears 122 are driven by a synchronous belt assembly. The worm gears 122 are meshed with the worm wheel 123. A driving rod 121 is rotatably connected between the upper parts of the left and right sides of the air preheater 1. The driving rod 121 is located between the worm gears 122 on the front and rear sides. The left side of the driving rod 121 and the upper part of the electric screw 10 are driven by a bevel gear assembly. The right side of the driving rod 121 and the right sides of the worm gears 122 on the inner sides of the front and rear sides are driven by a synchronous belt assembly.

[0035] First, connect the right side guide bucket 6 to an external air supply machine, then install the air preheater 1 at a position related to the boiler, start the heater 61, and then discharge the air into the right side guide bucket 6. The heater 61 heats the discharged air to turn it into hot air. The hot air in the right side guide bucket 6 is discharged into the air preheater 1 and contacts the preheating pipe 4, thus preheating the preheating pipe 4. The air that contacts the preheating pipe 4 continues to flow through the left side guide bucket 6 and is discharged. When the air flow is too large, start the drive motor 65 to drive the spur gear 66 to rotate. The rotation of the spur gear 66 drives the L-shaped rack 67 to move downward. The L-shaped rack 67 drives the baffle 63 to move downward. The baffle 63 moves downward to block one of the guide buckets 6 on the left and right sides, making it difficult for air to flow in. The air is discharged into the air preheater 1, and the air supply machine discharges the air into the air preheater 1 through the unblocked guide bucket 6, so that a small amount of air is discharged into the air preheater 1 and contacts the preheating pipe 4, thereby reducing the air flow entering the air preheater 1, and under the action of the partition 64, the air needs to pass through the partition 64 before it can be discharged through the left guide bucket 6. The partition 64 allows the air to flow longer in the air preheater 1, which is better for preheating. When the baffle 63 blocks one of the guide buckets 6 for two hours, the drive motor 65 can be started to drive the spur gear 66 to rotate in the opposite direction, and the spur gear 66 drives the L-shaped rack 67 to move upward and reset, and the L-shaped rack 67 drives the baffle 63 to move upward and reset, and the baffle 63 resets and stops to move the guide bucket 6 The side is blocked, and then a large amount of air is discharged into the air preheater 1. This is repeated to control the discharged air flow, and then the electric heating wire 11 is started, and then the electric screw 10 is started to rotate forward and reverse alternately to drive the n-type plate 9 to move up and down. The n-type plate 9 moves up and down to drive the scraper plate 8 to move up and down. The scraper plate 8 moves up and down to drive the electric heating wire 11 to move up and down. The scraper plate 8 drives the electric heating wire 11 to move up and down to fully heat the lower part of the preheating tube 4, so that the temperature of the preheating tube 4 is higher than the dew point of water vapor and acid gas in the flue gas. At the same time, the scraper plate 8 moves up and down to scrape off the dust attached to the outer wall of the preheating tube 4 to prevent the dust attached to the outer wall of the preheating tube 4 from affecting the heat exchange between the air and the flue gas, thereby ensuring the effect of the heat exchange between the air and the flue gas. When the flue gas is discharged into the intake When the flue gas in the air inlet hopper 3 is in the preheating tube 4, the flue gas flows downward through the preheating tube 4. Since the temperature of the lower part of the preheating tube 4 is higher than the dew point of water vapor and acid gas in the flue gas, the dust in the flue gas is not easy to adhere to the lower part of the preheating tube 4 and accumulate to cause blockage of the preheating tube 4. Then the flue gas continues to flow downward and is discharged through the air outlet hopper 2 for subsequent use. At the same time, the electric screw 10 rotates alternately forward and reverse and drives the driving rod 121 to rotate alternately forward and reverse through the bevel gear assembly. The driving rod 121 drives the inner worm 122 to rotate alternately forward and reverse through the synchronous belt assembly. The inner worm 122 rotates alternately forward and reverse through the synchronous belt assembly to drive the outer worm 122 to rotate alternately forward and reverse. The worm 122 drives the worm wheel 123 to rotate alternately forward and reverse.The worm gear 123 drives the annular plate 12 to rotate alternately forward and reversely, and the annular plate 12 drives the spiral scraper 1201 to rotate alternately forward and reversely. If dust is attached to the preheating tube 4, the spiral scraper 1201 can rotate alternately forward and reversely to scrape off the dust attached to the inner wall of the preheating tube 4. In this way, the heating effect of the spiral scraper 1201 and the electric heating wire 11 can prevent the dust from adhering to the inner wall of the preheating tube 4 and causing blockage, thereby improving the efficiency of flue gas flow. When the flue gas stops being discharged into the air inlet hopper 3, the air is stopped from being discharged into the air preheater 1, the heater 61 is turned off, and then the electric heating wire 11 and the electric screw 10 are turned off. The electric screw 10 stops driving the n-type plate 9 to move up and down, and the n-type plate 9 stops driving the scraper plate 8 to move up and down. At the same time, the electric screw 10 stops driving the driving rod 121 to rotate, and the annular plate 12 stops driving the spiral scraper 1201 to rotate.

[0036] See also Fig. 9 and Fig.10 As shown, the anti-blocking device for the boiler air preheater 1 also includes a filter assembly installed on the air outlet hopper 2, and the filter assembly includes an air collecting hopper 14, a vertical plate 141, a filter mesh plate 142 and a switching assembly. The air collecting hopper 14 is fixedly connected to the upper inner side of the air outlet hopper 2, and the air collecting hopper 14 can collect and guide the flue gas discharged from the preheating pipe 4. A vertical plate 141 is fixedly connected between the middle part of the outer side of the air collecting hopper 14 and the middle part of the inner side of the air outlet hopper 2. The vertical plate 141 can separate the inner side of the air outlet hopper 2 into two cavities. The filter mesh plates 142 are clamped at the lower parts of the left and right sides of the air outlet hopper 2. When the flue gas contacts the filter mesh plate 142, the filter mesh plate 142 can filter the dust in the flue gas. The air collecting hopper 14 and the vertical plate 141 are connected to each other. A switching component is arranged in the middle, and when the switching component is operated, the switching component can realize the switching of the direction of smoke flow; the switching component includes a perforated ball 143, a guide plate 144 and a stepper motor 145, and the perforated ball 143 is fixedly connected between the gas outlet end of the gas collecting hopper 14 and the vertical plate 141, and the holes of the perforated ball 143 are on the left and right sides, and a guide plate 144 is rotatably connected between the middle part of the perforated ball 143 and the vertical plate 141, and the guide plate 144 is arranged obliquely, and when the guide plate 144 rotates, the guide plate 144 can realize the switching of the direction of smoke flow, and a stepper motor 145 is installed at the lower part of the outer front side surface of the gas collecting hopper 14, and the output shaft end of the stepper motor 145 is fixedly connected to the shaft of the guide plate 144.

[0037] When the flue gas is discharged into the gas outlet hopper 2 through the preheating pipe 4, the flue gas and the gas collecting hopper 14 are discharged into the perforated ball 143, and the flue gas in the perforated ball 143 contacts the guide plate 144, which guides the flue gas. The guided flue gas is discharged into the right cavity separated by the gas outlet hopper 2 through the hole on the right side of the perforated ball 143, and the flue gas in the gas outlet hopper 2 contacts the right filter screen 142, which filters the dust in the flue gas, and the flue gas filtered with dust continues to be discharged downward for subsequent use. When the right filter screen 142 needs to be cleaned after filtering dust for a long time, the stepper motor 145 is started to drive the guide plate 144 to reverse forty-five degrees, and the guide plate 144 reverses forty-five degrees to block the hole on the right side of the perforated ball 143, and the guide plate 144 stops blocking the left side of the perforated ball 143. The guide plate 144 allows the smoke to pass through the hole on the left side of the perforated ball 143 and enter the cavity on the left side of the discharge hopper. The left filter screen plate 142 filters the dust in the smoke. At the same time, the operator can remove the right filter screen plate 142 for cleaning. After cleaning, the right filter screen plate 142 is placed back on the gas outlet hopper 2. In this way, there is no need to interrupt the discharge of smoke to clean the filter screen plate 142, thereby ensuring work efficiency. When it is necessary to clean the left filter screen plate 142, the drive motor 65 is started according to the above operation to drive the guide plate 144 to rotate 45 degrees forward to reset. The smoke is discharged into the cavity on the right side of the gas outlet hopper 2 and the dust is filtered by the right filter screen plate 142. The left filter screen plate 142 can be removed for cleaning. After cleaning, the left filter screen plate 142 is placed back on the gas outlet hopper 2. In this way, a large amount of dust in the smoke can be prevented from affecting subsequent use, thereby ensuring the effect of subsequent use of the smoke.

[0038] See also Fig.11 As shown, the anti-blocking device for the boiler air preheater 1 also includes a filter plate 15. The ends of the left and right guide buckets 6 are both equipped with filter plates 15. When the air contacts the filter plates 15, the filter plates 15 can filter impurities in the air.

[0039] When the air supply machine discharges air into the right guide bucket 6, the air first contacts the filter plate 15, and the filter plate 15 first filters part of the dust in the air. The air after dust filtering continues to be discharged into the air preheater 1 to exchange heat with the flue gas. In this way, the dust in the air can be prevented from adhering to the outer wall of the preheating tube 4 to affect the heat exchange, thereby ensuring the effect of heat exchange between air and flue gas.

[0040] Finally, it is necessary to point out that the above content is only used to help understand the technical solution of the present invention and cannot be understood as limiting the scope of protection of the present invention; non-essential improvements and adjustments made by technical personnel in the field of technology based on the above content of the present invention are all within the scope of protection required by the present invention.

Claims

1. A blocking prevention device for a boiler air preheater, comprising an air preheater (1) and an air outlet hopper (2) fixedly connected to the bottom circumference of the air preheater (1), an air inlet hopper (3) fixedly connected to the top of the air preheater (1) along the circumference, preheating pipes (4) fixedly connected and penetrated between the top and the bottom of the air preheater (1) at uniform intervals, a transverse plate (5) fixedly connected to the inside of the air preheater (1), and the preheating pipes (4) fixedly penetrate the transverse plate (5), characterized in that: The air preheater (1) also comprises a flow guide assembly, a guide rod (7), a scraper plate (8), an n-type plate (9), an electric screw rod (10), an electric heating wire (11) and a scraper assembly. The air preheater (1) is provided with a flow guide assembly for controlling the flow of air. The four corners of the bottom of the air preheater (1) are fixedly connected with guide rods (7). A scraper plate (8) located below the horizontal plate (5) is slidably mounted between the guide rods (7). The scraper plate (8) is slidably mounted on the preheating tube (4). The inner side of the scraper plate (8) is evenly spaced with electric heating wires (11). The scraper plate (8) is fixedly connected with an n-type plate (9). The n-type plate (9) is slidably mounted on the preheating tube (4). A movable through-type partition (64) is installed on the top of the horizontal plate (5) with an electric screw (10) threadedly connected to the n-type plate (9), the electric screw (10) is used to drive the n-type plate (9) to move up and down, and the n-type plate (9) drives the scraper plate (8) to move up and down, so that the scraper plate (8) moves up and down to heat the preheating tube (4) to a required temperature through the electric heating wire (11), and the scraper plate (8) can also scrape off dust attached to the outer wall of the preheating tube (4), and a scraper assembly is arranged between the electric screw (10) and the preheating tube (4) for scraping off dust attached to the inner wall of the preheating tube (4).

2. The anti-blocking device for a boiler air preheater according to claim 1, characterized in that: The guide assembly comprises guide buckets (6) symmetrically fixedly connected to both sides of the air preheater (1) to guide the discharged air, a heater (61) is fixedly connected to the inner side of the guide bucket (6), a shell (62) is fixedly connected between the guide bucket (6) and the air preheater (1), a baffle (63) is slidably connected to the shell (62), the baffle (63) slidably penetrates the guide bucket (6) and is used to block the discharged air, a partition (64) is fixedly connected between the cross plate (5) and the air preheater (1) to separate the lower part of the air preheater (1) into two parts, and a driving assembly is arranged between the shell (62) and the baffle (63) to drive the baffle (63) to move.

3. The anti-blocking device for a boiler air preheater according to claim 2, characterized in that: The driving assembly comprises a driving motor (65) mounted on the air preheater (1); the output shaft of the driving motor (65) passes through the housing (62) and is fixedly connected to a spur gear (66); and the baffle (63) is fixedly connected to an L-shaped rack (67) meshing with the spur gear (66).

4. The anti-blocking device for a boiler air preheater according to claim 3, characterized in that: The scraper assembly comprises an annular plate (12) rotatably connected to the top circumference of the preheating tube (4); a spiral scraper (1201) in contact with the inner wall of the preheating tube (4) is fixedly connected to the bottom of the annular plate (12) and is used to scrape off dust attached to the inner wall of the preheating tube (4); and a rotating assembly is provided between the annular plate (12) and the electric screw (10) to drive the annular plate (12) to rotate.

5. The anti-blocking device for a boiler air preheater according to claim 4, characterized in that: The rotating assembly comprises a worm wheel (123) fixedly connected to the circumference of the outer side surface of the annular plate (12); two groups of worm gears (122) are symmetrically rotatably connected between the two sides of the air preheater (1); each group of worm gears (122) has two worm gears; each group of two worm gears (122) are driven by a synchronous belt assembly; the worm gears (122) are meshed with the worm wheel (123); a driving rod (121) located between the worm gears (122) is rotatably connected between the two sides of the air preheater (1); the driving rod (121) and the electric screw (10) are driven by a bevel gear assembly; and the driving rod (121) and the inner worm gear (122) are driven by a synchronous belt assembly.

6. The anti-blocking device for a boiler air preheater according to claim 5, characterized in that: The anti-blocking device for the boiler air preheater (1) also includes a filtering assembly, which includes an air collecting hopper (14) fixedly connected to the inner side of the air outlet hopper (2) to collect and guide the smoke discharged from the preheating pipe (4), a vertical plate (141) fixedly connected between the air collecting hopper (14) and the air outlet hopper (2) to divide the inner side of the air outlet hopper (2) into two cavities, and filter screens (142) are clamped on both sides of the air outlet hopper (2) to filter dust in the smoke, and a switching assembly is provided between the air collecting hopper (14) and the vertical plate (141) to switch the direction of smoke flow.

7. The anti-blocking device for a boiler air preheater according to claim 6, characterized in that: The switching assembly includes a perforated ball (143) fixedly connected between the gas outlet end of the gas collecting hopper (14) and the vertical plate (141), the holes of the perforated ball (143) are located on the left and right sides, and a guide plate (144) arranged obliquely is rotatably connected between the middle part of the perforated ball (143) and the vertical plate (141) for switching the direction of smoke flow. A stepper motor (145) is installed on the gas collecting hopper (14), and the output shaft end of the stepper motor (145) is fixedly connected to the shaft of the guide plate (144).

8. The anti-blocking device for a boiler air preheater according to claim 7, characterized in that: The anti-blocking device for the boiler air preheater (1) also includes a filter plate (15) installed at the end of the guide bucket (6) for filtering impurities in the air.

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