Electrostatic Precipitation Cathode System for Trapping Positively Charged Dust

Abstract

The present invention discloses an electrostatic precipitation cathode system capable of collecting positively charged dust, which includes RS small barbed wires, dust collection cathode wires, and a cathode rapping device. The RS small barbed wires are distributed in all electric fields of the electrostatic precipitator and have barbs capable of tip discharge when the high-voltage power supply is energized. The dust collection cathode wires are only distributed in 1 to 3 electric fields near the air outlet of the electrostatic precipitator and can adsorb positively charged dust particles by using a negatively charged dust suction structure when the high-voltage power supply is energized. The cathode rapping device can regularly rap the dust collection cathode wires to remove positively charged dust particles, thereby effectively improving the electrostatic precipitation efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of electrostatic precipitators, particularly to the technical field of the cathode system of electrostatic precipitators. Background Art

[0002] Electrostatic precipitators are the mainstream equipment for removing industrial flue gas dust, and are widely used in industries such as electric power, iron and steel, cement, and chemical industry. They have the advantages of low pressure drop loss, no blockage, large flue gas treatment volume, and high dust removal efficiency. Electrostatic precipitators usually work with a corona electrode (cathode system) and a dust collecting electrode (anode system). Among them, the cathode system can generate corona after being energized and ionize the nearby air. Dust particles will collide with negative ions, be charged, and form negative particles during the process of flowing through the corona electrode and the dust collecting electrode with the flue gas. The negatively charged dust particles will move towards the anode plate under the action of the electric field force and gradually adsorb on the anode plate. (When the dust particles deposited on the anode plate reach a certain thickness, the rapping mechanism can rap the anode plate to make the dust layer fall into the ash hopper), and the purified gas is discharged from the tail of the electric field at the same time.

[0003] Inside the electrostatic precipitator, although most of the dust carries negative charges, there are still a small amount of dust carrying positive charges. This is because when the cathode system is applied with high voltage to generate corona discharge and charge the dust particles, the charges here can be either positive or negative, depending on the collision situation of electrons and ions with the dust particles respectively. Under normal circumstances, since the distance of the negatively charged ions generated by ionization when flying towards the anode system is relatively long (with more opportunities to collide with dust particles), there are more negatively charged dust particles, but this does not mean that there are no positively charged dust particles. The existing electrostatic precipitators usually have poor ability to remove positively charged dust particles, resulting in the problem of reduced dust removal efficiency caused by the escape of positively charged dust (especially in the context of the gradually increasing environmental protection requirements). That is to say, how to make the electrostatic precipitator be able to remove positively charged dust and negatively charged dust, so that the dust removal efficiency can meet the increasingly strict requirements, is an urgent problem to be solved.

[0004] In addition, in the cathode system, the cathode wire is usually strip-shaped and there are several thorns for discharging on the outer wall, such as the BS thorn wire of the cathode of the electrostatic precipitator with the publication number CN201446012U and the thorn plate discharge cathode wire of an electrostatic precipitator with the publication number CN105817329A. After long-term use of such cathode wires, there are phenomena that some thorns are bent or even broken, resulting in maintenance personnel having to replace the entire cathode wire. This not only wastes materials but also increases the equipment maintenance cost. Summary of the Invention

[0005] The purpose of the present invention is to solve the problems in the prior art, and propose an electrostatic precipitator cathode system that can capture positively charged dust, which can remove positively charged dust particles, thereby effectively improving the electrostatic precipitator efficiency.

[0006] To achieve the above object, the present invention provides an electrostatic precipitation cathode system capable of collecting positively charged dust, including RS small barbs, dust collection cathode wires, and a cathode rapping device. The RS small barbs are distributed in all electric fields of the electrostatic precipitator and have barbs that can discharge at the tip when the high-voltage power supply is energized. The dust collection cathode wires are only distributed in 1 to 3 electric fields near the air outlet of the electrostatic precipitator and can adsorb positively charged dust particles using a negatively charged dust suction structure when the high-voltage power supply is energized. The cathode rapping device can regularly rap the dust collection cathode wires.

[0007] Preferably, the RS small barbs and the dust collection cathode wires are at the same potential when the high-voltage power supply is energized.

[0008] Preferably, the dust suction structure is a dust suction mesh plate or a dust suction hole box. On the one hand, the dust suction hole box can allow positively charged dust particles to enter the box cavity through the air holes located on the peripheral side wall, and on the other hand, it can discharge the positively charged dust particles out of the box cavity through the openings located on the bottom wall.

[0009] Preferably, when the dust suction structure is a dust suction hole box, a gas guide plate is further provided in the box cavity. The gas guide plate has a gas guide cylinder disposed opposite to the air hole, and the inner diameter of the cylinder gradually decreases from the side close to the air hole to the side far from the air hole.

[0010] Preferably, the dust suction hole box is also provided with a plug extending inward at the air hole, and the gas guide cylinder has a socket for the plug to be inserted.

[0011] Preferably, a suction hood with an upward-facing opening is further provided in the box cavity, and the suction hood is connected to a suction pump through a suction pipe.

[0012] Preferably, support members are respectively provided on the left and right sides of the dust suction structure. The support members are straight tubes formed by winding a base plate, and a wrapping portion extending outward is provided at the closed end. The wrapping portion can clamp the dust suction structure along the edge.

[0013] Preferably, the upper and lower ends of the support member are respectively flattened and provided with holes to form a pressed head, and a reinforcing plate is filled at the core layer of the pressed head.

[0014] Preferably, the RS small barbs and the dust collection cathode wires are respectively vertically suspended through a cathode frame. The cathode frame is connected to the outer shell of the electrostatic precipitator through a cathode suspension, and the cathode rapping device can apply a rapping force to the cathode frame.

[0015] Preferably, the RS small barbs further include a base tube. The barbs are directly thread-connected to the base tube or welded to the surface of a tube strip spirally wound outside the base tube, and the tube strip is thread-connected to the base tube.

[0016] The beneficial effects of the present invention:

[0017] 1) By installing dust collection cathode wires in 1 - 3 electric fields near the outlet of the electrostatic precipitator, the dust collection area can be increased by using the ash - absorbing structure with negatively charged dust collection cathode wires, the corona current can be increased, and a dust collection electric field with a uniform and relatively high average field strength can be generated to adsorb positively charged dust particles, thereby effectively improving the electrostatic precipitation efficiency (the dust concentration at the outlet of the electrostatic precipitator can be reduced by 5 - 10 mg / m 3 ). It has good overall adaptability (facilitating the transformation of old electrostatic precipitators), low transformation cost, and significant efficiency improvement;

[0018] 2) The dust collection cathode wires also have a certain inhibitory effect on back corona (the dust collection cathode wires can better prevent the back corona phenomenon of high - specific - resistance dust), and can improve the adaptability to high - specific - resistance dust (the dust removal efficiency for high - specific - resistance dust can be increased by more than 10%);

[0019] 3) By using an ash - absorbing hole box as the ash - absorbing structure, the positively charged dust particles can be temporarily stored in its box cavity, and the air - guiding plate located in the box cavity can use the gradually shrinking air - guiding cylinder from outside to inside to guide the positively charged dust particles into the box cavity on the one hand and prevent the positively charged dust particles temporarily stored in the box cavity from leaking out along the air holes due to the rapping action and causing secondary dust - raising phenomenon on the other hand;

[0020] 4) By installing a suction hood with an upward - facing hood mouth in the box cavity and synchronously opening and closing the suction pump and the cathode rapping device, a downward suction force can be given to the positively charged dust particles in the box cavity by the suction action of the suction hood at the beginning of each rapping operation, further preventing the generation of secondary dust - raising phenomenon;

[0021] 5) By directly screwing the barbs onto the base tube or welding them onto the surface of the tube band spirally wound outside the base tube (while threading the tube band to the base tube), it is convenient to disassemble and assemble some barbs individually or quickly remove all barbs at once, reducing material waste and cutting down on operation and maintenance costs.

[0022] The features and advantages of the present invention will be described in detail through embodiments in combination with the accompanying drawings. Brief Description of the Drawings

[0023] Figure 1 is the assembly schematic diagram of Embodiment 1;

[0024] Figure 2 is the assembly schematic diagram of RS small barb wire, dust collection cathode wire, cathode rapping device, cathode suspension, and cathode frame;

[0025] Figure 3 is the front view of the RS small barb wire in Embodiment 1;

[0026] Figure 4 is the front view of the dust collection cathode wire in Embodiment 1;

[0027] Figure 5 is Figure 4 the sectional view taken along the A-A direction of

[0028] Figure 6 is Figure 4 the sectional view taken along the B-B direction of

[0029] Figure 7 is the dust collection schematic diagram of the dust collection cathode wire of the second embodiment;

[0030] Figure 8 is the top view of the dust collection cathode wire of the second embodiment;

[0031] Figure 9 is Figure 8 the enlarged schematic diagram at position C of

[0032] Figure 10 is the dust collection schematic diagram of the dust collection cathode wire of the third embodiment;

[0033] Figure 11 is the front view of the RS small thorn wire of the fourth embodiment.

[0034] In the figure: 1 - the electrostatic precipitation cathode system that can capture positively charged dust, 11 - the RS small thorn wire, 111 - the base tube, 1111 - the tube body convex edge, 1112 - the socket, 112 - the barb, 12 - the dust collection cathode wire, 121 - the support member, 1211 - the edge wrapping part, 1212 - the profiled head, 1213 - the reinforcing plate, 122 - the dust suction structure, 1221 - the box cavity, 1222 - the plug, 123 - the air guiding plate, 1231 - the air guiding cylinder, 1232 - the socket, 124 - the suction hood, 13 - the cathode rapping device, 14 - the cathode suspension, 15 - the cathode frame, 2 - the anode plate, 3 - the outer shell, 4 - the high-voltage power supply. Specific Embodiments

[0035] Embodiment 1:

[0036] Refer to Figures 1 to 6, the electro-precipitation cathode system of the present invention for capturing positively charged dust includes RS small barbed wires 11, dust collection cathode wires 12, and a cathode rapping device 13. The RS small barbed wires 11 are distributed in all electric fields of the electrostatic precipitator and have barbs 112 that can discharge at the tip when the high-voltage power supply 4 is energized. The dust collection cathode wires 12 are only distributed in the fourth and fifth electric fields of the electrostatic precipitator and can adsorb positively charged dust particles using the negatively charged dust-absorbing structure 122 when the high-voltage power supply 4 is energized. The cathode rapping device 13 can regularly rap the dust collection cathode wires 12. Among them, for the electric fields with dust collection cathode wires 12, one set of dust collection cathode wires 12 is arranged between every two adjacent sets of the RS small barbed wires 11. Taking an electrostatic precipitator with a total of five electric fields as an example, setting the dust collection cathode wires 12 in its last two electric fields along the flue gas direction can effectively capture the positively charged dust and achieve the purpose of reducing the dust concentration at the outlet of the electrostatic precipitator.

[0037] The RS small barbed wires 11 and the dust collection cathode wires 12 maintain an equipotential (negative high voltage) when the high-voltage power supply 4 is energized.

[0038] The dust-absorbing structure 122 is a dust-absorbing mesh plate (which can first form a steel mesh through a profiled steel plate and then use the steel mesh as the dust-absorbing mesh plate). The dust-absorbing mesh plate can increase the dust collection surface area, and the mesh holes can also facilitate the smooth passage of air flow and ion wind, so that the positively charged dust is more easily adsorbed under the combined action of electric field force, air flow, and ion wind.

[0039] Supporting members 121 are respectively arranged on the left and right sides of the dust-absorbing structure 122. The supporting members 121 are straight pipes formed by winding a base plate, and a flanging portion 1211 extending outward is provided at the closed end. The flanging portion 1211 can clamp the dust-absorbing structure 122 along the edge. Among them, the supporting members 121 can play an overall supporting role for the dust collection cathode wires 12, so that the dust collection cathode wires 12 maintain straightness and flatness (the shape deviation requirements of the dust collection cathode wires 12 are flat straightness ≤ 3 mm, side straightness ≤ 3 mm, flat twist ≤ 3 mm, and flat waviness ≤ 3 mm), thereby ensuring that the distance between the dust collection cathode wires 12 and the anode plate 2 remains consistent and a uniform and stable electric field is formed. The dust-absorbing mesh plate plays the role of adsorbing and capturing positively charged dust. In addition, for further reinforcement, the supporting members 121 and the dust-absorbing structure 122 can also be welded to each other (specifically, the welding point spacing in the middle section is controlled at 50 - 100 mm, and the welding point spacing at both ends is controlled at 10 - 30 mm).

[0040] The upper and lower ends of the support member 121 are respectively flattened and perforated to form a corrugated head 1212, and the corrugated head 1212 is also filled with a reinforcing plate 1213 at the core layer; specifically, the corrugated head 1212 is formed by first installing the reinforcing plates 1213 at the upper and lower ends of the support member 121, and then flattening and perforating them as an integral whole; the corrugated head 1212 enables a flat connection between the support member 121 and the cathode frame 15 (easy installation), and the reinforcing plate 1213 can also increase the rigidity of the corrugated head 1212, thereby ensuring that the support member 121 can still maintain stability in use (i.e., a longer service life) after being subjected to long-term vibration and cleaning.

[0041] The RS small barb wire 11 and the dust collecting cathode wire 12 are respectively kept vertically suspended by the cathode frame 15, and the cathode frame 15 is connected to the outer casing 3 of the electrostatic precipitator through the cathode hanger 14. The cathode rapping device 13 can give a rapping force to the cathode frame 15; wherein, the cathode rapping device 13 needs to be arranged in the installation direction of the dust collecting cathode wire 12, and at least one of the cathode frames 15 where the two connecting heads of each dust collecting cathode wire 12 are located needs to be equipped with a cathode rapping device 13, so as to achieve effective cleaning.

[0042] The RS barb wire 11 also includes a base tube 111, and the barbs 112 are directly threadedly connected to the base tube 111; wherein, a tube body flange 1111 can be added to the outer edge of the base tube 111 to facilitate the installation of the barbs 112 (workers can replace one or several barbs 112 individually); in addition, sockets 1112 can be respectively provided at the upper and lower ends of the base tube 111 to be plugged into the cathode frame 15.

[0043] The dust collecting cathode wire 12 is also required to have 1) a flat and smooth surface without large rust spots and burrs; 2) be coated with vapor phase anti-rust oil (brand SYQ-10); 3) have a smooth transition without gaps; and 4) be overall not spliced ​​in width and length.

[0044] The working process of this embodiment:

[0045] When the high-voltage power supply 4 is energized, the cathode assembly composed of the RS barbed wire 11, the dust collection cathode wire 12, and the cathode frame 15 is negatively charged with high voltage, and the anode plate 2 is grounded. Thus, on the one hand, the barbs 112 provide corona discharge through the tips, and on the other hand, an electric field is formed between the cathode assembly and the anode plate 2 (i.e., an electric field force is provided through the high-voltage potential difference); after the air is ionized to form positive and negative charges and are respectively adsorbed on the dust surface, the ultrafine dust and the positively charged dust are mainly adsorbed on the dust collection cathode wire 12, while the negatively charged dust will be adsorbed onto the anode plate 2 under the action of the electric field force; in addition, the cathode rapping device 13 can periodically strike the cathode frame 15 to vibrate the RS barbed wire 11 and the dust collection cathode wire 12 located on the cathode frame 15, thereby automatically completing the dust removal operation; this design can solve the problem that conventional electrostatic precipitators cannot effectively capture positively charged dust and ultrafine dust.

[0046] Embodiment Two:

[0047] Refer to Figures 7 to 9 , the ash suction structure 122 is an ash suction hole box. On the one hand, the ash suction hole box can allow the positively charged dust particles to enter the box cavity 1221 through the air holes located on the peripheral side wall, and on the other hand, it can discharge the positively charged dust particles out of the box cavity 1221 through the openings located on the bottom side wall.

[0048] A gas guide plate 123 is also provided in the box cavity 1221. The gas guide plate 123 has a gas guide cylinder 1231 disposed opposite to the air hole, and the inner diameter of the cylinder gradually decreases from the side close to the air hole to the side far from the air hole; among them, the gas guide plate 123 is threadedly connected to the ash suction hole box through fasteners for easy disassembly and cleaning in the later stage; the gas guide plate 123 can effectively prevent the dust in the box cavity 1221 from leaving along the air hole due to the rapping action and causing the secondary dust-raising phenomenon by using the gas guide cylinder 1231.

[0049] The ash suction hole box is also provided with a plug 1222 extending inward at the air hole, and the gas guide cylinder 1231 has a socket 1232 for the plug 1222 to be inserted.

[0050] Others are the same as in Embodiment One.

[0051] Embodiment Three:

[0052] Refer to Figure 10 , a suction hood 124 with an upward-facing hood mouth is also provided in the box cavity 1221. The suction hood 124 is connected to a suction pump through a suction pipe; in addition, a filter can be installed on the pipeline of the suction pipe to prevent dust from entering the suction pump; during use, whenever the cathode rapping device 13 starts to rap, the suction pump can use the suction hood 124 to suck the hood mouth, thereby further preventing the generation of the secondary dust-raising phenomenon.

[0053] Others are the same as in Embodiment Two.

[0054] Embodiment 4:

[0055] Refer to Figure 11 , the barbs 112 are welded to the surface of the pipe belt 113 that is spirally wound outside the base pipe 111, and the pipe belt 113 is threadedly connected to the base pipe 111; during maintenance, workers can separate the pipe belt 113 from the base pipe 111, so as to remove all the barbs 112 located outside the base pipe 111 at one time.

[0056] Others are the same as Embodiment 1.

[0057] The above embodiments are illustrative of the present invention, not restrictive of the present invention. Any solution obtained by simply transforming the present invention falls within the protection scope of the present invention.

Claims

1. An electrostatic precipitator cathode system capable of capturing positively charged dust, characterized in that: It comprises an RS small barbed wire (11), a dust collecting cathode wire (12) and a cathode rapping device (13), wherein the RS small barbed wire (11) is distributed in all electric fields of the electrostatic precipitator and has a barb (112) which can discharge at the tip when the high-voltage power supply (4) is powered on, the dust collecting cathode wire (12) is distributed only in 1 to 3 electric fields near the gas outlet of the electrostatic precipitator and can absorb positively charged dust particles using a negatively charged dust absorbing structure (122) when the high-voltage power supply (4) is powered on, and the cathode rapping device (13) can perform regular rapping on the dust collecting cathode wire (12); The ash absorption structure (122) is an ash absorption hole box. The ash absorption hole box can use the air holes located on the peripheral box wall to allow positively charged dust particles to enter the box cavity (1221) on the one hand, and can use the openings located on the bottom box wall to discharge the positively charged dust particles out of the box cavity (1221) on the other hand. The box cavity (1221) is also provided with an air guide plate (123). The air guide plate (123) has an air guide cylinder (1231) arranged opposite to the air hole, and the inner diameter of the cylinder gradually decreases from the side close to the air hole to the side away from the air hole. The air guide plate (123) is threadedly connected to the ash absorption hole box via a fastener. The ash absorption hole box is also provided with a plug (1222) extending inward at the air hole. The air guide cylinder (1231) has a socket (1232) for the plug (1222) to be plugged in. A suction hood (124) with its hood opening facing upward is also provided in the box cavity (1221); the suction hood (124) is connected to a suction pump via a suction pipe.

2. The electrostatic precipitator cathode system capable of capturing positively charged dust according to claim 1, characterized in that: The RS small barbed wire (11) and the dust collecting cathode wire (12) maintain the same potential when the high voltage power supply (4) is powered on.

3. The electrostatic precipitator cathode system capable of capturing positively charged dust according to claim 1, characterized in that: Support members (121) are provided on the left and right sides of the dust suction structure (122), respectively; the support member (121) is a straight tube formed by winding a base plate and has an outwardly extending edge portion (1211) at the closing end; the edge portion (1211) can clamp the dust suction structure (122) along the edge.

4. The electrostatic precipitator cathode system capable of capturing positively charged dust according to claim 3, characterized in that: The upper and lower ends of the support member (121) are respectively flattened and opened to form a profiled head (1212), and the profiled head (1212) is also filled with a reinforcing plate (1213) at the core layer.

5. The electrostatic precipitator cathode system capable of capturing positively charged dust according to claim 1, characterized in that: The RS small barbed wire (11) and the dust collecting cathode wire (12) are respectively kept vertically suspended by a cathode frame (15); the cathode frame (15) is connected to the outer shell (3) of the electrostatic precipitator through a cathode hanger (14); and the cathode rapping device (13) can give a rapping force to the cathode frame (15).

6. The electrostatic precipitator cathode system capable of capturing positively charged dust according to any one of claims 1 to 5, characterized in that: The RS barbed wire (11) further comprises a base pipe (111), the barbs (112) being directly threadedly connected to the base pipe (111) or welded to the surface of a pipe band (113) spirally wound outside the base pipe (111), and the pipe band (113) being threadedly connected to the base pipe (111).

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