A device for preventing ash from blocking the bottom of the ash hopper of a dry electrostatic precipitator

Abstract

The utility model belongs to the field of electric dust removal, and particularly relates to an anti-dust blocking device at the bottom of an ash hopper of a dry electrostatic dust collector, comprising an ash hopper, a back-blowing system, a fluidized air main pipe and an ash conveying system. The ash hopper is an inverted cone structure, and the bottom is connected to a bin pump. The bottom end of the bin pump is connected to an ash conveying pipeline, one end of the ash conveying pipeline is connected to an ash bin, and the other end is connected to a compressed air pipeline. Back-blowing holes are provided on both sides of the side walls of the ash hopper, and the head end of a carbon steel short section extends into the ash hopper through the back-blowing hole and is installed with a conical umbrella cap. A manual ball valve and a check valve are provided at the rear end of the carbon steel short section located outside the ash hopper, and the end of the carbon steel short section is connected to a rubber hose, and the other end of the rubber hose is connected to a fluidized air main pipe, and the fluidized air main pipe is connected to a compressed air pipeline. The device has a simple structure, and the back-blowing system and the ash conveying system are automatically operated at the same time, thereby improving the ash conveying speed, and there is no need to stop the machine to empty the ash hopper, so as to avoid dense accumulation of ash in the ash hopper or heavy and sticky ash, and avoid high material level collapse accidents in the ash hopper caused by long-term operation.

Description

Technical Field

[0001] The utility model belongs to the field of electric dust removal, and in particular relates to a ash blocking prevention device at the bottom of an ash hopper of a dry electrostatic dust collector. Background Art

[0002] A 300MW coal-fired boiler generates a large amount of flue gas during the combustion process. The boiler flue gas carries a large amount of dust. After passing through the dry electrostatic precipitator, a large amount of dust can fall into the ash hopper. The dust is transported to the ash storage for comprehensive utilization through the pneumatic ash conveying system. The dry electrostatic precipitator is a double-chamber five-field ash collector. The ash collection volume of the first field accounts for 80%, the ash collection volume of the second field accounts for 10%, and the ash collection volume of the third, fourth, and fifth fields accounts for 10%. The first field produces a large amount of ash. During operation, it is affected by factors such as boiler load fluctuations, the physical and chemical characteristics of fly ash, and ammonia escape. The bottom of the ash hopper is prone to dust compaction and blockage, resulting in poor ash discharge. The original design of the bottom of the ash hopper is equipped with a fluidizing air system, whose function is to increase the fluidity of the ash at the bottom of the ash hopper under the drive of the fluidizing air, so that the ash can be discharged smoothly from the ash hopper.

[0003] The electrostatic precipitator hopper fluidized air system is designed as a mother pipe control, that is, each electric field is equipped with a gasification air mother pipe, the mother pipe is equipped with a main door, and each ash hopper is equipped with a gasification air branch pipe, which is directly connected to the gasification plate inside the ash hopper. During operation, the gasification plate inside the ash hopper often wears out or the gasification fan stops abnormally, and the ash inside the ash hopper flows back into the gasification air branch pipe, blocking the pipeline. The ash at the bottom of the ash hopper cannot be effectively fluidized, and the ash is hardened on the inner wall of the ash hopper, resulting in uneven ash discharge or blockage. In severe cases, an ash hopper high material level accident will occur, posing a safety hazard. In addition, if a certain ash hopper gasification air duct is blocked, it cannot be repaired and dredged online, and it is necessary to shut down and empty the ash hopper before processing, which affects the stable operation of the host unit and the electrostatic precipitator system. Utility Model Content

[0004] The utility model aims to provide a device for preventing ash from blocking the bottom of an ash hopper of a dry electrostatic precipitator, so as to solve the problem that the existing ash hopper gasification air system often suffers from wear and tear of the gasification plate inside the ash hopper, ash flows back into the gasification air branch pipe, blocks the pipe, and the ash hopper gasification air pipe is blocked and cannot be cleared online, requiring shutdown to empty the ash hopper for post-processing, thus affecting the normal operation of the unit.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A device for preventing ash from being blocked at the bottom of an ash hopper of a dry electrostatic precipitator comprises an ash hopper, a backflush system, a fluidizing air main pipe and an ash conveying system, wherein the ash conveying system comprises an ash conveying pipeline, a silo pump and an ash bin. The ash hopper is an inverted cone structure, and its bottom is connected to the silo pump. A manual plug-in door is arranged at the bottom of the ash hopper, and a pneumatic swing valve is arranged at the top of the silo pump. A soft connection is adopted between the manual plug-in door and the pneumatic swing valve. During operation, the manual plug-in door is always open, and the pneumatic swing valve can automatically convey ash. The bottom of the silo pump is connected to the ash conveying pipeline, one end of the ash conveying pipeline is connected to the ash bin, and the other end is connected to the compressed air pipeline through the main air valve. Backflush holes are arranged on both sides of the side walls of the ash hopper, and the backflush holes are connected to the backflush system. The backflush system is connected to the fluidizing air main pipe, and the fluidizing air main pipe is connected to the compressed air pipeline through the main air valve.

[0007] The back-blowing system includes a conical umbrella cap, a carbon steel short joint, a manual ball valve, a check valve and a rubber hose. The head end of the carbon steel short joint extends into the ash hopper through the back-blowing hole and is installed with a conical umbrella cap. The opening of the conical umbrella cap is inclined upward and toward the center of the ash hopper. A manual ball valve and a check valve are arranged at the rear end of the carbon steel short joint located outside the ash hopper. The manual ball valve is normally open during operation. The end of the carbon steel short joint is connected to the rubber hose through a clamp, and the other end of the rubber hose is connected to the fluidizing air main pipe through a clamp.

[0008] The back-blowing hole is located 10 cm above the manual plug-in door.

[0009] The carbon steel short section has a diameter of 15 mm and a length of 20 cm.

[0010] The rubber hose has a diameter of 20 mm and a length of 3 m.

[0011] Beneficial effects achieved by the utility model:

[0012] (1) The dust collector hopper is equipped with a back-blowing system, which enables the back-blowing system and the ash conveying system to start and stop automatically at the same time, thereby increasing the ash conveying speed. The blockage of the ash hopper back-blowing air duct can be cleared online without stopping the machine to empty the ash hopper or manual operation. The back-blowing time can be adjusted according to the changes in ash volume and ash quality, which is flexible to operate.

[0013] (2) The compressed air pressure in the back-blowing system is 0.2 MPa. After the back-blowing air is blocked by the conical cap inside the ash hopper, it bypasses the conical cap downward and then blows the compacted ash upward evenly, making the ash fall evenly to prevent the ash from blocking the pipeline and ensuring the stable operation of the ash conveying system. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the utility model.

[0015] Explanation of the reference numerals: 1. ash hopper; 2. silo pump; 3. carbon steel short section; 4. conical umbrella cap; 5. fluidizing air main pipe; 6. rubber hose; 7. manual ball valve; 8. check valve; 9. manual plug-in door; 10. pneumatic swing valve; 11. backblowing hole; 12. main air valve; 13. ash conveying pipeline; 14. ash silo; 15. compressed air pipeline. DETAILED DESCRIPTION

[0016] The technical solution of the utility model is further described below in conjunction with the accompanying drawings and specific embodiments.

[0017] like Figure 1 As shown, a device for preventing ash from blocking the bottom of an ash hopper of a dry electrostatic precipitator comprises an ash hopper 1, a backflush system, a fluidizing air main pipe 5 and an ash conveying system, wherein the ash conveying system comprises an ash conveying pipeline 13, a silo pump 2 and an ash silo 14, the backflush system comprises a conical umbrella cap 4, a carbon steel short joint 3, a manual ball valve 7, a check valve 8 and a rubber hose 6, the ash hopper 1 is an inverted cone structure, the bottom of which is connected to the silo pump 2, a manual plug-in door 9 is provided at the bottom of the ash hopper 1, a pneumatic swing valve 10 is provided at the top of the silo pump 2, the manual plug-in door 9 and the pneumatic swing valve 10 are provided, and the manual plug-in door 9 and the pneumatic swing valve 10 are provided. 0 is connected with a soft connection. During operation, the manual plug-in door 9 is always open, and the pneumatic swing valve 10 can automatically transport ash. The bottom end of the silo pump 2 is connected to the ash transport pipeline 13. One end of the ash transport pipeline 13 is connected to the ash bin 14, and the other end is connected to the compressed air pipeline 15 through the main air valve 12. Backflush holes 11 are opened on both sides of the side wall of the ash hopper 1 at 10 cm above the manual plug-in door 9. Carbon steel short sections 3 are welded on the backflush holes 11. The diameter of the carbon steel short section is 15 mm and the length is 20 cm. The head end of the carbon steel short section 3 passes through the backflush hole 11. It extends into the ash hopper 1 and is installed with a conical umbrella cap 4. The opening of the conical umbrella cap 4 is inclined upward and toward the center of the ash hopper 1. A manual ball valve 7 and a check valve 8 are arranged at the rear end of the carbon steel short section 3 outside the ash hopper. The manual ball valve is normally open during operation. The end of the carbon steel short section 3 is connected to a rubber hose 6 through a clamp. The diameter of the rubber hose is 20 mm and the length is 3 m. The other end of the rubber hose 6 is connected to a fluidizing air main pipe 5 through a clamp. The fluidizing air main pipe 5 is connected to a compressed air pipeline 15 through a main air valve 12. By adding back-blowing holes, carbon steel nipples and rubber hoses, the back-blowing and ash conveying of the ash hopper can be started and stopped at the same time, thereby increasing the ash conveying speed and preventing the ash from being compacted and blocked at the bottom of the ash hopper due to poor fluidity when the ash is heavy and sticky. By using a conical umbrella cap and a check valve, the problem of low gasification air volume can be avoided. After the back-blowing air is blocked by the conical umbrella cap, it bypasses the conical umbrella cap downward and then blows the compacted ash upward evenly, ensuring that the ash falls evenly and smoothly and avoiding blockage of the ash conveying pipeline.

Claims

1. A device for preventing ash blocking at the bottom of an ash hopper of a dry electrostatic precipitator, characterized in that: The invention comprises an ash hopper (1), a backflush system, a fluidizing air main pipe (5) and an ash conveying system, wherein the ash conveying system comprises an ash conveying pipeline (13), a silo pump (2) and an ash storage (14). The ash hopper (1) is an inverted cone structure, and its bottom is connected to the silo pump (2). A manual plug-in door (9) is provided at the bottom of the ash hopper (1), and a pneumatic swing valve (10) is provided at the top of the silo pump (2). A soft connection is adopted between the manual plug-in door (9) and the pneumatic swing valve (10). The bottom of the silo pump (2) is connected to the ash conveying pipeline (13), one end of the ash conveying pipeline (13) is connected to the ash storage (14), and the other end is connected to a compressed air pipeline (15) through a main air valve (12). Backflush holes (11) are provided on both sides of the side wall of the ash hopper (1), and the backflush holes (11) are connected to the backflush system. The backflush system is connected to the fluidizing air main pipe (5), and the fluidizing air main pipe (5) is connected to the compressed air pipeline through the main air valve (12).

2. The device for preventing ash blocking at the bottom of the ash hopper of a dry electrostatic precipitator according to claim 1, characterized in that: The backflush system comprises a conical umbrella cap (4), a carbon steel short section (3), a manual ball valve (7), a check valve (8) and a rubber hose (6). The head end of the carbon steel short section (3) extends into the ash hopper (1) through a backflush hole (11) and is installed with the conical umbrella cap (4). The opening of the conical umbrella cap (4) is inclined upward and faces the center of the ash hopper (1). The rear end of the carbon steel short section (3) located outside the ash hopper (1) is provided with a manual ball valve (7) and a check valve (8). The end of the carbon steel short section (3) is connected to the rubber hose (6) through a clamp, and the other end of the rubber hose (6) is connected to the fluidizing air main pipe (5) through a clamp.

3. The device for preventing ash blocking at the bottom of the ash hopper of a dry electrostatic precipitator according to claim 2, characterized in that: The backflush hole (11) is located 10 cm above the manual plug-in door (9).

4. The device for preventing ash blocking at the bottom of the ash hopper of a dry electrostatic precipitator according to claim 3, characterized in that: The carbon steel short section (3) has a diameter of 15 mm and a length of 20 cm.

5. A device for preventing ash blocking at the bottom of an ash hopper of a dry electrostatic precipitator according to any one of claims 3 or 4, characterized in that: The rubber hose (6) has a diameter of 20 mm and a length of 3 m.

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