CN103586135B - Formation mode of dust collection pole plate and ash removal water film of wet-type electric precipitator - Google Patents

Abstract

The invention relates to a dust-collecting pole plate of a wet-type electric dust collector and a method for forming a dust-cleaning water film thereof. The method is as follows: use a dust collection plate made of high temperature resistant and corrosion resistant materials, and set the water distribution pipeline inside the plate to ensure reliable and stable operation of the plate and evenly distribute water to the surface of the plate; The fiber woven film uses capillary action to form a complete and uniform dust-removing water film on the surface of the plate, avoiding secondary dust and improving the collection efficiency of particulate matter, especially fine particulate matter.

Description

A dust-collecting pole plate of a wet electrostatic precipitator and its formation method of ash-cleaning water film

Technical field

The invention belongs to environmental protection equipment, in particular to a dust-collecting pole plate of a wet-type electric dust collector and a method for forming a dust-cleaning water film thereof.

Background technique

The wet electrostatic precipitator uses a layer of water film formed on the dust collecting plate to clean the dust collected on the plate when it flows downward. Compared with the dry electrostatic precipitator: the wet electrostatic precipitator does not need a rapping device, thereby avoiding the secondary dust caused by the rapping, and also preventing the secondary dust caused by the air flow and corona wind; because the electrode plate is always distributed With the downward flowing water film, the dust trapped on the electrode plate is immediately washed away by the water film, so for high specific resistance dust, there will be no back corona, avoiding the secondary dust caused by it; for low For specific resistance dust, the trapped particles will not escape from the plate and return to the airflow again. Due to the above advantages, the wet electrostatic precipitator has a very high dust removal efficiency and can adapt to dust with various specific resistances.

Most of the existing wet electrostatic precipitators are plate type or cylinder type. Since the water film in the wet electrostatic precipitator flows downward on the pole plate by gravity, if it encounters obstacles or geometric changes on the surface of the pole plate, the flow direction will be changed, and phenomena such as "convergence" and "fork flow" will occur. A complete and uniform dust-removing water film cannot be formed under the plate, and the collected dust cannot be cleaned up in time, and it will accumulate and become thicker, which will cause the corona electrode to discharge the accumulated dust, and even affect the power supply of the electrostatic precipitator, causing the precipitator to fail to operate normally. The current coal-fired power generation units are often large, which also puts forward greater requirements on the amount of flue gas treated by the dust collector, which also leads to a relatively large design size of the corresponding wet electrostatic precipitator, with a plate length of more than ten meters or even more than twenty meters. The height will make it more difficult to evenly distribute the water film on the plates. Traditional wet electrostatic precipitators use steel dust-collecting pole plates, which are expensive, and the wet dust-collecting environment will cause corrosion to ordinary steel pole plates. Using special steel pole plates or anti-corrosion treatment on the pole plates is also a Not a small investment. In addition, wet electrostatic precipitators often need a large amount of ash cleaning water in order to collect the collected dust, which cannot meet the requirements for intensive utilization of water resources, and will produce a large amount of ash cleaning water, causing secondary pollution to the environment. Secondary pollution is also not conducive to the comprehensive utilization of fly ash.

Contents of the invention

The purpose of the present invention is to solve the problem that a complete and uniform water film cannot be formed on the dust collecting plate of the wet electrostatic precipitator, so that the wet electrostatic precipitator can run stably in a coal-fired power plant, and provide a method that can reduce investment costs, reduce corrosion, The invention discloses a dust-collecting plate of a wet-type electrostatic precipitator which saves water consumption and a method for forming a dust-cleaning water film.

To achieve the above object, the present invention adopts the following technical solutions:

A dust collecting pole plate of a wet dust collector. The main body is made of heat-resistant plastic, ceramic materials and other materials, which can withstand the high temperature and corrosion environment in the electric dust collector. The surface of the pole plate is smooth and flat, and it has certain rigidity and mechanical strength. Meet the performance requirements of hanging and running in the electrostatic precipitator. The water distribution pipes of the dust collection plate of the wet electrostatic precipitator are located inside the plate and arranged in sequence along the flow direction of the flue gas. There is a main water supply pipe at the bottom of the dust collection plate to connect the various water distribution pipes, and through the internal water distribution pipe Route down-up water supply. The water distribution pipeline leads all the way to the top of the dust collection plate, and there are water distribution holes at the corresponding positions on the top of the plate, and water is distributed to the plate through overflow.

The water distribution holes on the dust-collecting pole plate supply water to the dust-collecting pole plate in a balanced manner, and the initial pressure, flow velocity and flow rate of the water flowing downward at each point above the pole plate along the airflow direction are the same.

The dust-collecting plate is generally formed by laminating two identical structural plates, and the grooves on the two plates form a water delivery pipeline after splicing. For the convenience of maintenance and replacement, the entire dust collection plate is spliced by several vertical dust collection plates.

A method for forming a dust-cleaning water film of a wet electrostatic precipitator, in which a fiber woven film is suspended and covered on a dust collecting pole plate, and the film is attached to the surface of the pole plate, which is beneficial to the formation of a uniform water film.

The fiber woven film is generally carbon fiber, silicon fiber, polypropylene or polyester, and has good capillary action and water distribution characteristics. Utilizing the capillary action of the braided fibers can make the dust-cleaning water film more evenly and stably distributed on the surface of the dust-collecting plate.

In order to ensure a good water film is formed on the pole plate, the pole plate should be degreased before covering the pole plate with a fiber woven film to remove surface oil.

The beneficial effects of the present invention are:

(1) Adopt the dust-collecting plate of the present invention, utilize the water distribution pipeline evenly distributed inside the plate, and the capillary action of the fiber woven film covered on the surface of the plate, can effectively solve the problem of cleaning water on the surface of the plate surface of the wet electrostatic precipitator The problem of uniform distribution of the film.

(2) The dust removal water film is uniform and complete, and the dust removal effect is good. There will be no dead spots for dust removal on the plate, and no dust blocks that will affect the integrity of the water film. Therefore, there will be no discharge phenomenon of corona wires to dust accumulation, ensuring The power supply is stable to ensure the normal operation of the electrostatic precipitator.

(3) Cost saving. Compared with the traditional wet electrostatic precipitator steel plate, the cost of the dust collection plate using new materials is lower, and the capital investment in corrosion prevention is also greatly reduced.

(4) Save water, use evenly distributed pipelines for water supply, and distribute water through the capillary characteristics of the fiber woven film to form a uniform water film, which can effectively reduce the amount of water used to maintain a uniform water film. With the reduction of water consumption, the scale of cleaning water recycling equipment is reduced, and the amount of cleaning water treatment is reduced, which in turn reduces the investment and operation costs of equipment.

(5) Easy installation and maintenance. Compared with the traditional wet electrostatic precipitator steel plate, the dust collection plate made of new material is lighter, and the installation and maintenance are more convenient. The form of splicing of dust-collecting pole plates is adopted, so that only the corresponding pole plates need to be removed for replacement and maintenance during pole plate maintenance.

Description of drawings

Figure 1 is a front view of the dust collecting plate of the wet electrostatic precipitator. In the figure, 1 is the fiber woven film covered on the surface of the pole plate; 4 is the water supply pipe for the dust collector plate; 5 is the water volume control valve of the water supply pipe.

Fig. 2 is a full sectional view of the dust collecting plate of the wet electrostatic precipitator. In the figure, 1 is the fiber woven film covered on the surface of the plate; 2 is the dust collection plate of the electrostatic precipitator; 3 is the water distribution pipeline inside the dust collection plate; 4 is the water supply pipe for the dust collection plate; 5 is the water volume control of the water supply pipe valve.

Fig. 3 is a vertical cross-sectional view of A-A of the dust collecting pole plate of the wet electrostatic precipitator. In the figure, 1 is the fiber woven film covered on the surface of the plate; 2 is the dust collection plate of the electrostatic precipitator; 3 is the water distribution pipeline inside the dust collection plate; 4 is the water supply pipe for the dust collection plate.

Fig. 4 is a horizontal cross-sectional view of B-B of the dust collecting pole plate of the wet electrostatic precipitator.

Fig. 5 is a schematic diagram of a single electrode plate of a wet electrostatic precipitator and its C-C horizontal section view.

detailed description

Embodiment: As shown in Fig. 1, Fig. 2 and Fig. 3, it mainly includes: 1. Fiber woven film; 2. Dust collecting plate of electrostatic precipitator; 3. Water distribution pipeline inside the dust collecting plate; 4. Dust collecting pole The plate water supply pipeline is formed, and the water supply pipeline water volume control valve 5 is arranged on the dust collection plate water supply pipeline. The fiber woven film 1 is pasted and fixed on the surface of the dust collecting pole plate 2, as shown in FIG. 3 . The water supply pipeline 4 of the dust collection plate connects the internal water distribution pipeline 3 of each dust collection plate to supply gray flushing water thereto, as shown in FIG. 2 . The dust collector plate 2 of the electrostatic precipitator is generally assembled by two identical single dust collector plates as shown in FIG. 5 , and the effect can be seen in FIG. 4 . The dust collecting pole plate 2 of the electrostatic precipitator is suspended inside the shell of the wet electrostatic precipitator, and the lower part is grounded.

During operation, the dust-containing gas enters the dust removal part and is charged. Driven by the force of the electric field, the charged dust particles move to the fiber woven film 1 on the dust collecting plate. The ash removal water enters the dust collection plate water supply pipeline 4 driven by the water transfer pump, and is transported by it to the internal water distribution pipeline 3 of each dust collection plate. The flow of the ash removal water is regulated by the pipeline water volume control valve 5. The cleaning water is transported to the top of the dust collection plate 2 of the electrostatic precipitator, and is distributed to the fiber woven film 1 on the surface of the dust collection plate by way of overflow. The dedusting water in the fiber woven film 1 flows downward under the action of gravity to wash down the dust particles on the surface of the film. The ash removal water generally enters the corresponding ash removal water recycling system and is recycled after treatment.

Claims (3)

1. A dust-collecting pole plate of a wet electrostatic precipitator, characterized in that the main body is made of two heat-resistant plastic or ceramic materials with the same structure and certain rigidity and mechanical strength, and a fiber woven film is attached to the surface , the grooves on the two pole plates form a water distribution pipeline after they are bonded together. The water distribution pipeline is located inside the pole plate and arranged vertically along the flue gas flow direction. There is a main water supply pipeline at the bottom of the dust collecting pole plate to connect each The water distribution pipelines are connected together, and the water is supplied from the bottom to the top through the internal water distribution pipeline. The water distribution pipeline leads to the top of the dust collecting plate. There are water distribution holes at the corresponding position on the top of the plate, and the water is distributed to the plate through the form of overflow. water. 2. The dust collecting pole plate of the wet electrostatic precipitator according to claim 1, characterized in that the pole plate is formed by laminating two plates of the same structure, and the grooves on the two pole plates are formed after lamination. The water distribution pipeline is formed, and the water distribution pipeline is evenly arranged along the flow direction of the flue gas to ensure uniform water supply to the pole plate in the direction of the pole plate. all the same. 3. a method for forming a dust-cleaning water film of the dust-collecting pole plate of a wet-type electrostatic precipitator as claimed in claim 1, characterized in that, after degreasing the dust-collecting pole plate with certain rigidity and mechanical strength, on its surface Lay fiber woven film, use the capillary action of fiber woven film to distribute the cleaning water evenly and quickly on the surface of the film.