CN204247379U - A kind of vertical wide-space wet electrical dust precipitator - Google Patents

Abstract

The utility model discloses a vertical wide-spacing wet-type electrostatic precipitator, which comprises a casing and an airflow distribution plate, a cathode fixing frame, several dust collecting pipes, several cleaning nozzles, and gas The inlet is set on the side wall of the shell below the air distribution plate, and the gas outlet is set on the top of the shell; among them, the dust collection pipe is a square pipe with a side length of 350mm-600mm and a length of 2000-6000mm; several dust collection pipes The tubes form a dust collection tube bundle; each dust collection tube is provided with a discharge electrode wire, and the discharge electrode wire is fixed by a cathode fixing frame; the cathode fixing frame is connected to a high-voltage power supply outside the casing. The utility model has the advantages of simple structure, small occupied area, high removal efficiency of fine particles, saving investment and energy consumption.

Description

A Vertical Wide Spacing Wet Electrostatic Precipitator

technical field

The utility model relates to a vertical wide-spacing wet electrostatic precipitator, which belongs to the technical field of air pollution control.

Background technique

At present, the flue gas desulfurization of coal-fired boilers mainly adopts wet desulfurization technology. During the operation of the wet desulfurization system, PM _2.5 such as SO ₃ acid mist, slurry drop aerosol, or ammonia salt aerosol is produced, causing serious harm to human health and the environment. As a high-efficiency composite pollution control technology at the end of coal-fired boiler flue gas, wet electrostatic precipitator technology can effectively capture these fine particles (PM _2.5 dust, SO ₃ acid mist, aerosol) and heavy metals, and effectively solve landscape pollution such as "gypsum rain" question.

However, the distance between the same electrodes of the existing wet electrostatic precipitator is generally 250-350mm, and the secondary voltage is 45-80kV. The narrow electrode spacing restricts the injection of higher operating voltage to a certain extent, resulting in limited charging ability for fine particles, especially submicron particles; at the same time, under the condition of narrow electrode spacing, the uniformity of current density on the surface of the electrode plate is poor, and the ion wind The disturbance effect is strong, which affects the uniformity of the liquid film on the surface of the plate; therefore, in general, under the condition of narrow spacing, the wet electrostatic precipitator has limited ability to remove fine particles, especially submicron particles. In addition, the consumption of steel (or glass fiber reinforced plastic) and the cost of processing unit gas are also high when narrow-pitch wet electrostatic precipitators are used.

Utility model content

The purpose of this utility model is to provide a vertical wide-spacing wet electrostatic precipitator, which can effectively improve the removal efficiency of fine particles, especially submicron particles, in flue gas after wet desulfurization, and save investment and energy consumption.

In order to achieve the above object, the utility model adopts the following technical solutions:

A vertical wide-spacing wet electrostatic precipitator, which includes a shell and an airflow distribution plate, a cathode fixing frame, several dust collecting pipes, and several cleaning nozzles arranged in the shell from bottom to top. On the side wall of the shell below the plate, the gas outlet is set on the top of the shell; among them, the dust collection pipe is a square pipe with a side length of 350mm-600mm and a length of 2000-6000mm; several dust collection pipes form a dust collection tube bundle ; There is a discharge electrode wire inside each dust collection tube, and the discharge electrode wire is fixed by the cathode fixed frame; the cathode fixed frame is connected to the high-voltage power supply outside the casing.

Preferably, the trunk of the discharge electrode wire is a square tube or a round tube, and its inscribed circle diameter or inner diameter is 10-40mm, and the outer surface of the trunk of the discharge electrode wire is uniformly arranged with sawtooth or fishbone line. Four serrations or herringbone lines are evenly arranged on the outer surface of the main body of the discharge electrode wire in the same section. The distance between adjacent sawtooth tips or herringbone tips in the discharge electrode wires is 10-40mm, and the distance between the serration tips or herringbone tips and the outer surface of the discharge electrode trunk is 5-40mm. Each sawtooth tip or herringbone tip of the discharge electrode wire is perpendicular to the corresponding inner surface of the dust collecting pipe.

Preferably, the gas flow distribution plate adopts a structure in which vertical baffles are arranged under the perforated plate, the number of vertical baffles is 3-5, and the height of the vertical baffles increases correspondingly with the increase of the distance from the gas inlet. In order to more evenly distribute the gas flow load in each dust collection pipe, two layers of air flow distribution plates can be set above the gas inlet.

Preferably, in order to enhance the dust cleaning effect on the surface of the dust collection pipes, the cleaning nozzles are arranged directly above the central axis of each dust collection pipe.

The beneficial effects of the utility model are:

(1) The utility model adopts a wide electrode spacing structure, which can increase the operating voltage of the wet electrostatic precipitator, and the secondary voltage can reach 80kV ~ 120kV, which enhances the charging ability of fine particles, especially submicron particles; at the same time, the high-voltage discharge electrode near the The ion wind is enhanced, which increases the driving speed of the charged fine particles; under the condition of wide spacing, the uniformity of the current density on the surface of the plate is improved, and the disturbance of the ion wind on the surface of the plate is weak, which has little influence on the uniformity of the liquid film on the surface of the plate , thereby increasing the capture efficiency.

(2) The utility model adopts four-sided sawtooth or four-sided fishbone-shaped discharge electrode wire, which can improve the line current density and its uniformity; it adopts the discharge electrode matching form combining a square dust collection tube with a four-side discharge electrode wire, which improves the discharge inside the dust collection tube. The uniformity of the electric field distribution improves the effective utilization of the dust collection surface in the dust collection pipe. In addition, the four-sided discharge electrode wire is used, which is firm and reliable, has high mechanical strength, and is not easy to break and drop.

(3) The airflow distribution plate described in the utility model can optimize the airflow distribution, evenly distribute the gas flow load in each dust collecting pipe, and the flow load deviation is not more than 10%. The utility model can effectively enhance the dust-cleaning ability on the surface of the dust-collecting pipes by correspondingly arranging a nozzle just above each dust-collecting pipe, and prevent dust and scaling on the inner surface of the dust-collecting pipes.

(4) Compared with the traditional wet electrostatic precipitator technology, the utility model can enhance the removal efficiency of fine particles; the floor area is small, the specific dust collection area is less than 20m ² /m ³ /s, and the consumption of steel (or glass fiber reinforced plastic) Reduced by more than 30%.

Description of drawings

Fig. 1 is the structural representation of the vertical wide-spacing wet electrostatic precipitator of the present utility model;

Fig. 2 is the structural representation of dust collection pipe bundle;

Figure 3a is a schematic structural view of a four-sided sawtooth discharge electrode wire (the trunk is a square tube);

Figure 3b is a schematic structural view of the four-sided sawtooth discharge electrode wire (the trunk is a round tube);

Fig. 4a is a schematic structural view of a four-sided herringbone-shaped discharge electrode wire (trunk is a square tube);

Fig. 4b is a structural schematic diagram of a fishbone-shaped discharge electrode wire (trunk is a round tube) on four sides;

Fig. 5 a is the top view after the combination of the discharge electrode wire (trunk is a square tube) and the dust collection tube;

Figure 5b is a top view of the combination of the discharge electrode wire (trunk is a round tube) and the dust collection tube;

Fig. 6 is a schematic diagram of the structure of the air distribution plate.

Reference signs:

1 Gas inlet 2 Airflow distribution plate 3 Cathode fixed frame 4 Discharge electrode wire 5 Dust collection pipe 7 Gas outlet 8 Cleaning nozzle 9 High voltage power supply 10 Liquid circulation pump

Detailed ways

As shown in Figure 1, the vertical wide-spacing wet electrostatic precipitator of the present invention includes a housing and an airflow distribution plate 2, a cathode fixing frame 3, several dust collecting pipes 5, several A cleaning nozzle 8, the gas inlet 1 is arranged on the side wall of the housing below the air flow distribution plate 2, and the gas outlet 7 is arranged on the top of the housing; wherein, the dust collecting pipe is a square pipe with a side length of 350mm to 600mm and a length of 2000-6000mm; as shown in Figure 2, several dust collection tubes 5 form a dust collection tube bundle, each dust collection tube 5 is provided with a discharge electrode wire 4, the discharge electrode wire 4 is fixed by the cathode fixed frame 3; the cathode is fixed Frame 3 is connected with high-voltage power supply 9 outside the housing.

The discharge electrode wire 4 is a four-sided sawtooth (as shown in Fig. 3a, 3b) or a four-sided fishbone-shaped discharge electrode wire (as shown in Fig. 4a, Fig. 4b). Wherein, the trunk of the discharge electrode wire 4 is a square tube or a round tube, and the diameter or inner diameter of the inscribed circle thereof is 10-40 mm. The outer surface of the main body of the discharge electrode wire 4 is evenly arranged with sawtooth or herringbone lines perpendicular to the main body of the discharge electrode line. In addition, four sawtooth or herringbone lines are evenly arranged on the outer surface of the trunk at the same section. The distance between adjacent sawtooth tips or herringbone tips in the discharge electrode wire 4 is 10-40 mm, and the distance between the serration tips or herringbone tips and the outer surface of the discharge electrode trunk is 5-40 mm. Each sawtooth tip or herringbone tip of the discharge electrode wire 4 is perpendicular to the corresponding inner surface of the dust collecting tube 5 (as shown in Fig. 5a, Fig. 5b).

As shown in Figure 6, the gas flow distribution plate 2 adopts the structure of vertical baffles arranged under the perforated plate, the number of vertical baffles is 3 to 5, and the height of the vertical baffles increases with the increase of the distance from the gas inlet. In order to more evenly distribute the gas flow load in each dust collection pipe, 2 layers of air flow distribution plates can be installed above the gas inlet.

In addition, in order to enhance the dust cleaning effect on the surface of the dust collection pipes 5, the cleaning nozzles 8 are arranged directly above the central axis of each dust collection pipe 5.

The method for purifying flue gas after wet desulfurization by utilizing the above-mentioned utility model is as follows:

After the flue gas enters the shell from the gas inlet 1, it passes through the airflow distribution plate 2 to evenly distribute the airflow, and then enters the dust collection pipe 5. After being charged by the high-voltage electric field in the dust collection pipe 5, the charged solid and liquid fine particles in the flue gas , collected to the inner surface of dust collection pipe 5 under the action of electric field force. The particles collected on the inner wall of the dust collection pipe 5 are regularly cleaned and removed by the cleaning nozzle 8 . During this process, the operating voltage is controlled at 80kV-120kV, the gas velocity in the dust collecting pipe 5 is controlled at 2-3.5m/s, and the residence time is 2-5s.

The above-mentioned vertical wide-spacing wet electrostatic precipitator is used to purify the flue gas after wet desulfurization, the specific dust collection area is less than 20m ² /m ³ /s, the removal efficiency of PM _2.5 can reach more than 85%, and the emission concentration is lower than 10mg/m ³ .

Claims (8)

1. A vertical wide-spacing wet electrostatic precipitator is characterized in that it includes a housing and an airflow distribution plate, a cathode fixed frame, several dust collecting pipes, and several cleaning nozzles arranged successively in the housing from bottom to top, The gas inlet is set on the side wall of the shell below the airflow distribution plate, and the gas outlet is set on the top of the shell; among them, the dust collection pipe is a square pipe with a side length of 350mm-600mm and a length of 2000-6000mm; The dust tubes form a dust collection tube bundle; each dust collection tube is provided with a discharge electrode wire, and the discharge electrode wire is fixed by a cathode fixing frame; the cathode fixing frame is connected to a high-voltage power supply outside the casing. 2. The vertical wide-spacing wet electrostatic precipitator according to claim 1, characterized in that, the trunk of the discharge electrode wire is a square tube or a round tube, the diameter or inner diameter of the inscribed circle is 10-40mm, and the The outer surface of the main body of the discharge electrode wire is uniformly arranged with sawtooth or herringbone lines perpendicular to the main body of the discharge electrode line. 3. The vertical wide-spacing wet electrostatic precipitator according to claim 2, characterized in that 4 sawtooth or herringbone lines are evenly arranged on the outer surface of the main body in the same section of the discharge electrode wire. 4. The vertical wide-spacing wet electrostatic precipitator according to claim 2 or 3, characterized in that the distance between adjacent sawtooth tips or fishbone line tips in the discharge electrode line is 10-40mm, and the distance between the sawtooth tips or fishbone line tips The distance between the tip of the bone wire and the outer surface of the main body of the discharge electrode is 5-40 mm. 5. The vertical wide-spacing wet electrostatic precipitator according to claim 2 or 3, characterized in that, each sawtooth tip or herringbone tip of the discharge electrode wire is perpendicular to the corresponding inner surface of the dust collection tube. 6 . The vertical wide-spacing wet electrostatic precipitator according to claim 1 , characterized in that, the air flow distribution plate adopts a structure in which vertical baffles are arranged under a perforated plate, and the number of vertical baffles is 3-5. 7. The vertical wide-spacing wet electrostatic precipitator according to claim 1 or 6, characterized in that the airflow distribution plate has two layers. 8. The vertical wide-spacing wet electrostatic precipitator according to claim 1, characterized in that, the cleaning nozzles are arranged directly above the central axis of each dust collecting pipe.