CN110833931A - Spray water treatment system of electric dust collector under negative pressure working condition - Google Patents

Abstract

The invention discloses an electrostatic precipitator spray water treatment system under a negative pressure working condition, which belongs to the technical field of coal gas treatment and comprises a top spray water device and a bottom water storage tank which are arranged in a wet type electrostatic precipitator cylinder and are communicated up and down, wherein a sewage tank, a filter, a clean water tank and the spray water device are sequentially connected behind the water storage tank through pipelines, a check valve and a bypass pipe are sequentially arranged on the pipeline between the water storage tank and the sewage tank, the other end of the bypass pipe is connected back to the cylinder, the connecting point of the connecting point and the cylinder is higher than the liquid level of the sewage tank, and the height difference between the connecting point and the cylinder is larger than the liquid column height which can be. The system can reduce the water level of the water storage tank at the bottom of the wet electric dust collector and the water level of the sewage tank caused by the change of the negative pressure of the working condition to the maximum extent, prevent the dust deposition of the sewage tank and reduce the energy consumption of the fan.

Description

A spray water treatment system of electrostatic precipitator under negative pressure condition

technical field

The invention belongs to the technical field of gas treatment, and in particular relates to a spray water treatment system of an electrostatic precipitator under negative pressure conditions.

Background technique

The primary converter flue gas generated in the process of converter steelmaking has complex components and large temperature fluctuations, requiring a stable and reliable dust removal system. With the improvement of environmental protection requirements of domestic iron and steel enterprises, the existing wet dust removal process can no longer meet the emission requirements of flue gas. In order to meet the standard or even ultra-low emission of flue gas, some domestic steel mills have embedded wet circular electrostatic precipitators in the existing wet dust removal process, and purified the gas through electrostatic precipitation technology. Due to land occupation and other reasons, the wet electrostatic precipitator is generally installed in front of the fan, and the pressure during operation fluctuates periodically between -5kPa and -25kPa. In order to ensure the reliable dust removal of the wet electrostatic precipitator, the system generally requires a separate circulating water treatment system to wash the dust attached to the anode plate, and discharge the dust-laden water to the sewage pool for treatment and recycling. However, in the discharge of dusty water, the commonly used U-shaped positive pressure water seal will keep the water level of the water storage tank at the bottom of the wet power station at a high level for a long time, and the dust will settle in the drain outlet, resulting in a drainage accident; insert the drain pipe into the pool to form negative pressure water As the working condition pressure fluctuates between -5 and -25 kPa, if the liquid level of the sewage pool and the bottom of the wet electrostatic precipitator storage tank are not high enough, the sewage will flow back from the sewage tank to the storage tank periodically. The drop in the water tank of the dust collector is as high as 2m, which wastes energy consumption and causes the water level in the sewage tank to fluctuate greatly.

SUMMARY OF THE INVENTION

In view of this, the purpose of the present invention is to provide a spray water treatment system for an electrostatic precipitator under negative pressure conditions, which can prevent the backflow of sewage in the sewage pool under the normal working condition of the wet electrostatic precipitator, and realize the realization of The spray water system is energy-saving and recycled.

The present invention is achieved through the following technical solutions:

The invention provides a spray water treatment system for an electrostatic precipitator under negative pressure conditions, which includes a top spray water device and a bottom water storage tank, which are arranged in the wet electrostatic precipitator cylinder and communicated up and down. Connect the sewage tank, filter, clean water tank and spray water device, and set a one-way valve and a bypass pipe in sequence on the pipeline between the water storage tank and the sewage tank. The access point is higher than the liquid level of the sewage pool, and the height difference between the two is greater than the height of the liquid column that can be raised by the negative pressure of the cylinder under high working conditions.

Further, the bottom of the sewage tank is laid with an external compressed air pipeline and an aeration pipe with several upward nozzles.

Further, the top of the sewage pool is provided with a dosing device.

Further, an intermediate water pump is provided on the pipeline between the sewage pool and the filter.

Further, the filter is a sand filter, the filtered water enters the clean water tank through the pipeline, and the suspended matter enters the sludge tank through the pipeline after filtering.

Further, a water supply pump is provided on the pipeline between the clear water pool and the water spray device.

Further, the top of the clear water pool is provided with an automatic water replenishing device.

Further, a liquid level switch is arranged inside the clean water tank.

The advantages of the present invention are:

1. When the negative pressure of the system is low, the drainage from the bottom water storage tank will be discharged to the sewage pool through the one-way valve. When the negative pressure of the working condition is high, the bottom water storage tank will stop the drainage, and the sewage will flow back to the bypass under the action of negative pressure. The pipe fluctuates in the pipe, which can minimize the changes in the water level of the bottom storage tank and the water level of the sewage pool caused by the change of the negative pressure of the working condition, and reduce the energy consumption of the fan.

2. The system is equipped with a dosing device and compressed air purging through the sewage tank to condense the fine dust in the sewage tank and prevent it from depositing to the bottom of the tank, extending the cleaning cycle of the sewage tank.

3. In this system, the sewage enters the clean water tank after being treated by the sand filter, and is sent to the top spray water device through the water supply pump, so as to realize the energy saving and recycling of the spray water.

Other advantages, objects, and features of the present invention will be set forth in the description that follows, and will be apparent to those skilled in the art based on a study of the following, to the extent that is taught in the practice of the present invention. The objectives and other advantages of the present invention may be realized and attained by the following description.

Description of drawings

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail below in conjunction with the accompanying drawings, wherein:

Fig. 1 is the structural representation of the present invention;

Component label description: 1. Sprinkler water device, 2. Water storage tank, 3. Check valve, 4. Bypass pipe, 5. Cylinder body, 6. Compressed air pipeline, 7. Sewage pool, 8. Intermediate water pump, 9. Sand filter, 10. Sludge tank, 11. Aeration pipe, 12. Dosing device, 13. Clear water tank, 14. Automatic water replenishment device, 15. Water supply pump, 16. Liquid level gauge.

Detailed ways

The embodiments of the present invention are described below through specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the drawings provided in the following embodiments are only used to illustrate the basic idea of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

As shown in FIG. 1 , in the spray water treatment system of the electrostatic precipitator under the negative pressure condition in this embodiment, the spray water device 1 at the top of the wet electrostatic precipitator cylinder 5 releases a large amount of water through its nozzle, and The dust is washed down from the dust collecting plate of the wet electrostatic precipitator and enters the water storage tank 2 at the bottom under the action of gravity, and the water storage tank 2 is connected to the sewage tank 7, the filter 9 and the clean water tank 13 in turn through the pipeline, and the treated The clean water in the clean water tank is circulated to the top spray water device 1 to realize the energy-saving recycling of spray water; at the same time, the pipeline between the water storage tank 2 and the sewage pool 7 is arranged in turn along the flow direction of the one-way valve 3. And the bypass pipe 4, the other end of the bypass pipe 4 is returned to the cylinder 5, and the access point with the cylinder 5 is higher than the normal liquid level of the sewage pool 7, and the height difference between the two is greater than the height of the cylinder 5. The height of the liquid column that can be raised by the negative pressure, that is, when the negative pressure in the working condition is not large, the sewage in the water storage tank 2 overcomes the resistance along the pipeline and is discharged to the sewage tank 7 through the one-way valve 3; When it is large, the sewage in the water storage tank 2 cannot be discharged by gravity, and the sewage in the sewage tank 7 flows back through the pipeline and enters the bypass pipe 4; The height difference of the liquid level in pool 7 is greater than the liquid level height under the maximum working condition negative pressure, so that the sewage cannot flow back to the wet electrostatic precipitator equipment when the maximum working condition negative pressure is guaranteed, and the sewage only fluctuates in the bypass pipe. Because the diameter of the bypass pipe is much smaller than the water storage tank of the wet electrostatic precipitator, the energy consumption is low, which can reduce the energy consumption of the fan.

In this embodiment, the upper part of the sewage tank 7 is provided with a dosing device, and the fine dust particles are agglomerated by adding flocculant. Compressed air is blown into the sewage tank through the aeration pipe to disturb the sewage tank and prevent the deposition of dust particles.

In this embodiment, the intermediate water pump 8 extracts the sewage in the sewage tank 7 , and sends it into the filter 9 for filtration, and the treated circulating water enters the clean water tank 13 . The filter adopts a sand filter. When the resistance of the sand filter is large, backwashing will be performed to discharge the filtered suspended matter into the sludge tank 10 .

The upper part of the clear water tank 13 in this embodiment is equipped with an automatic water replenishing device 14, and replenishes according to the water level set by the liquid level switch 16 set in the clear water tank.

In this embodiment, the water in the clear water tank 13 is lifted to the top spray water device 1 by the water supply pump 15 through the pipeline, so as to realize the spray water circulation and treatment of the wet electrostatic precipitator.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims (8)

1. The utility model provides an electrostatic precipitator spray water processing system under negative pressure operating mode, including locating top spray water installation (1) and bottom aqua storage tank (2) of wet-type electrostatic precipitator barrel (5) interior and upper and lower intercommunication, a serial communication port, connect gradually effluent water sump (7) through the pipeline behind the aqua storage tank, filter (9), clean water basin (13) and spray water installation, set gradually check valve (3) and bypass pipe (4) on the pipeline between aqua storage tank to the effluent water sump, the barrel is gone back into to the other end of bypass pipe, and be higher than effluent water sump liquid level height and the liquid column height that both difference in height were greater than the high-duty condition negative pressure of barrel and promoted with the access point of barrel.

2. The spray water treatment system of the electric dust collector under the negative pressure working condition as claimed in claim 1, wherein an external compressed air pipeline (6) is paved at the bottom of the sewage pool, and the aeration pipe (11) is provided with a plurality of upward nozzles.

3. The electric dust collector spray water treatment system under the negative pressure working condition as claimed in claim 1, wherein a dosing device (12) is arranged at the top of the sewage pool.

4. The spray water treatment system of the electric dust collector under the negative pressure working condition as recited in claim 1, wherein an intermediate water pump (8) is arranged on a pipeline between the sewage pool and the filter.

5. The electric precipitator spray water treatment system under the negative pressure working condition according to claim 1, wherein the filter is a sand filter, filtered water enters a clean water tank through a pipeline, and suspended matters in the filtered water enter a sludge tank (10) through a pipeline.

6. The spray water treatment system of the electric dust collector under the negative pressure working condition as claimed in claim 1, wherein a water supply pump (15) is arranged on a pipeline between the clean water tank and the spray water device.

7. The spray water treatment system of the electric dust collector under the negative pressure working condition as claimed in claim 1, wherein an automatic water replenishing device (14) is arranged at the top of the clean water tank.

8. The spray water treatment system of the electric dust collector under the negative pressure working condition as claimed in claim 1, wherein a liquid level switch (16) is arranged inside the clean water tank.

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