Electric precipitation cathode system capable of capturing dust with positive charges

Abstract

The invention discloses an electric dust removal cathode system capable of capturing positively charged dust, which comprises 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 an electric dust remover and are provided with barbs capable of discharging at points when a high-voltage power supply is electrified; the dust collection cathode wires are only distributed in 1-3 electric fields, close to an air outlet, of the electric dust remover and can absorb positively charged dust particles through the negatively charged dust absorption structure when the high-voltage power source is powered on, the cathode rapping device can regularly rap the dust collection cathode wires, the positively charged dust particles can be removed, and therefore the electric dust removal efficiency is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electrostatic precipitators, in particular to the technical field of electrostatic precipitator cathode systems. Background Art

[0002] Electrostatic precipitator is the mainstream equipment for industrial flue gas dust removal. It is widely used in power, steel, cement and chemical industries. It has the advantages of low pressure drop loss, no clogging, large flue gas processing volume and high dust removal efficiency. Electrostatic precipitator usually works together with corona electrode (cathode system) and dust collecting electrode (anode system). Among them, the cathode system can generate corona and ionize the nearby air after power is turned on. The dust particles will collide with negative ions, be charged and form negative particles while the flue gas flows through the corona electrode and the dust collecting electrode. The negatively charged dust particles will move toward 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 vibration mechanism can vibrate the anode plate to make the dust layer fall into the ash hopper), and the purified gas will be discharged from the tail of the electric field at the same time.

[0003] Although most of the dust inside the electrostatic precipitator carries a negative charge, there is still a small amount of dust that carries a positive charge. This is because when high voltage is applied to the cathode system to generate corona discharge and charge the dust particles, the charge here can be either positive or negative and depends on the collision of electrons and ions with the dust particles respectively. Under normal circumstances, since the negative ions generated by ionization have a longer distance when flying to the anode system (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. Existing electrostatic precipitators are usually poor in their ability to remove positively charged dust particles, and thus there is often a problem of reduced dust removal efficiency caused by the escape of positively charged dust (especially in the context of people's increasing requirements for environmental protection). In other words, how to enable the electrostatic precipitator to remove positively charged dust and negatively charged dust so that the dust removal efficiency can meet increasingly stringent requirements needs to be solved urgently.

[0004] In addition, in the cathode system, the cathode wire is usually in the shape of a long strip and has a number of barbs on the outer wall for discharge, such as the electrostatic precipitator cathode BS barb wire with announcement number CN201446012U and an electrostatic precipitator barb sheet discharge cathode wire with publication number CN105817329A; after long-term use, some barbs of this cathode wire are bent or even broken, which causes maintenance personnel to have to replace the entire cathode wire; this not only wastes materials, but also leads to an increase in equipment maintenance costs. Summary of the invention

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

[0006] To achieve the above-mentioned purpose, the present invention proposes an electrostatic precipitator cathode system that can capture positively charged dust, including RS small barbed wires, dust collecting 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 that can discharge at the tip when the high-voltage power supply is energized. The dust collecting cathode wires are only distributed in 1 to 3 electric fields near the air outlet of the electrostatic precipitator and can use a negatively charged ash-absorbing structure to absorb positively charged dust particles when the high-voltage power supply is energized. The cathode rapping device can regularly rap the dust collecting cathode wires.

[0007] Preferably, the RS small barbed wire and the dust collecting cathode wire maintain the same potential when the high voltage power supply is energized.

[0008] Preferably, the ash absorption structure is an ash absorption mesh plate or an ash absorption hole box. The ash absorption hole box can use the air holes located on the surrounding box walls to allow the positively charged dust particles to enter the box cavity 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 on the other hand.

[0009] Preferably, when the ash suction structure is an ash suction hole box, an air guide plate is further provided in the box cavity, and the air guide plate has an air guide cylinder 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.

[0010] Preferably, the ash suction hole box is further provided with a plug extending inwardly at the air hole, and the air guide cylinder has a socket for the plug to be plugged in.

[0011] Preferably, a suction hood with its hood opening facing upward 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 provided on the left and right sides of the dust suction structure respectively. The support members are straight tubes formed by winding a substrate and have an outwardly extending edging portion at the closing end. The edging 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 perforated to form a profiled head, and the profiled head is also filled with a reinforcing plate at the core layer.

[0014] Preferably, the RS small barbed wire and the dust collecting cathode wire are respectively kept vertically suspended by cathode frames, and the cathode frame is connected to the outer casing of the electrostatic precipitator through a cathode hanger, and the cathode rapping device can give a rapping force to the cathode frame.

[0015] Preferably, the RS barbed wire further comprises a base pipe, the barbs are directly threadedly connected to the base pipe or welded to the surface of a pipe band spirally wound outside the base pipe, and the pipe band is threadedly connected to the base pipe.

[0016] Beneficial effects of the present invention: 1) By installing dust collecting cathode wires in 1 to 3 electric fields near the outlet of the electrostatic precipitator, the dust collecting cathode wires with negative charge can be used to increase the dust collecting area, increase the corona current, and generate a uniform dust collecting electric field with high average field strength to absorb positively charged dust particles, thereby effectively improving the electrostatic precipitator efficiency (the dust concentration at the outlet of the electrostatic precipitator can be reduced by 5 to 10 mg / m 3 ), good overall adaptability (convenient for transformation of old electrostatic precipitators), low transformation cost and significant efficiency improvement; 2) The dust collecting cathode line also has a certain inhibitory effect on back corona (the dust collecting cathode line 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 of high specific resistance dust can be increased by more than 10%); 3) By using an ash suction hole box as an ash suction structure, the box cavity can be used to temporarily store positively charged dust particles, and the air guide plate located in the box cavity can also use the air guide cylinder that gradually shrinks from the outside to the inside to guide the positively charged dust particles into the box cavity on the one hand, and on the other hand, prevent the positively charged dust particles temporarily stored in the box cavity from leaking out along the air holes due to vibration and causing secondary dusting; 4) By installing a suction hood with the hood opening facing upward in the box cavity, and simultaneously starting and closing the suction pump and the cathode rapping device, at the beginning of each rapping operation, the suction effect of the suction hood can be used to give the positively charged dust particles a downward suction force in the box cavity, further preventing the occurrence of secondary dusting; 5) By directly threading the burrs onto the base pipe or welding them to the surface of the pipe band spirally wound outside the base pipe (while threading the pipe band to the base pipe), it is easy to disassemble and assemble some burrs individually or quickly remove all burrs at one time, thereby reducing material waste and reducing operation and maintenance costs.

[0017] The features and advantages of the present invention will be described in detail through embodiments in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is an assembly diagram of the first embodiment; Figure 2 It is the assembly diagram of RS small barbed wire, dust collecting cathode wire, cathode rapping device, cathode hanging and cathode frame; Figure 3 It is a front view of the RS small thorn wire of the first embodiment; Figure 4 is a front view of the dust collecting cathode line of the first embodiment; Figure 5 yes Figure 4 AA section view; Figure 6 yes Figure 4 BB section view; Figure 7 is a dust collecting schematic diagram of the dust collecting cathode line of the second embodiment; Figure 8 is a top view of the dust collecting cathode line of the second embodiment; Fig. 9 yes Figure 8 An enlarged schematic diagram of point C; Fig.10 is a dust collecting schematic diagram of the dust collecting cathode line of the third embodiment; Fig.11 It is a front view of the RS small thorn wire of embodiment 4.

[0019] In the figure: 1-an electrostatic precipitator cathode system capable of collecting positively charged dust, 11-RS small barbed wire, 111-base tube, 1111-tube body convex edge, 1112-socket, 112-thorn, 12-dust collecting cathode wire, 121-support, 1211-edge wrapping part, 1212-profile head, 1213-reinforcement plate, 122-ash suction structure, 1221-box cavity, 1222-plug, 123-air guide plate, 1231-air guide cylinder, 1232-socket, 124-suction hood, 13-cathode rapping device, 14-cathode hanging, 15-cathode frame, 2-anode plate, 3-housing, 4-high voltage power supply. DETAILED DESCRIPTION

[0020] Embodiment 1: See also Figures 1 to 6 The present invention is an electrostatic precipitator cathode system capable of capturing positively charged dust, comprising RS small barbed wires 11, dust collecting cathode wires 12 and cathode rapping device 13, wherein the RS small barbed wires 11 are distributed in all electric fields of the electrostatic precipitator and have barbs 112 capable of discharging at the tip when the high-voltage power supply 4 is powered on, the dust collecting cathode wires 12 are only distributed in the fourth electric field and the fifth electric field of the electrostatic precipitator and can absorb positively charged dust particles by 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 regularly rap the dust collecting cathode wires 12; wherein, for the electric field having the dust collecting cathode wires 12, a group of dust collecting cathode wires 12 is arranged between each two adjacent groups of the RS small barbed wires 11; taking an electrostatic precipitator having five electric fields in total as an example, by arranging the dust collecting cathode wires 12 in the last two electric fields along the flue gas direction, the positively charged dust can be effectively captured, thereby achieving the purpose of reducing the dust concentration at the outlet of the electrostatic precipitator.

[0021] The RS small barbed wire 11 and the dust collecting cathode wire 12 maintain the same potential (negative high voltage) when the high voltage power supply 4 is powered on.

[0022] The ash absorbing structure 122 is an ash absorbing mesh plate (a steel mesh can be first formed by a corrugated steel plate, and then the steel mesh is used as a fine ash mesh plate); the ash absorbing mesh plate can increase the dust collecting surface area, and the mesh holes can also facilitate the smooth passage of airflow and ion wind, so that positively charged dust can be more easily adsorbed under the combined action of electric field force, airflow and ion wind.

[0023] The left and right sides of the ash absorbing structure 122 are respectively provided with support members 121, and the support member 121 is a straight tube formed by winding a substrate and is provided with an outwardly extending edging portion 1211 at the closing end, and the edging portion 1211 can clamp the ash absorbing structure 122 along the edge; wherein, the support member 121 can play an overall supporting role for the dust collecting cathode line 12, so that the dust collecting cathode line 12 maintains straightness and flatness (the shape deviation requirements of the dust collecting cathode line 12 are plane straightness ≤3mm, side straightness ≤3mm, plane distortion ≤3 mm and plane corrugation ≤3 mm), thereby ensuring that the distance between the dust collecting cathode line 12 and the anode plate 2 remains consistent and forms a uniform and stable electric field; the ash absorbing mesh plate plays a role in absorbing and capturing positively charged dust; in addition, in order to further reinforce, the support member 121 and the ash absorbing structure 122 can also be welded (specifically, the spacing between the welding points in the middle section is controlled at 50-100mm, and the spacing between the welding points at the two ends is controlled at 10-30mm).

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] The working process of this embodiment: When the high-voltage power supply 4 is powered on, the cathode assembly composed of the RS barbed wire 11, the dust collecting cathode wire 12 and the cathode frame 15 carries a negative high voltage, and the anode plate 2 is grounded, so that on the one hand, the barbs 112 provide corona discharge through the tip, and on the other hand, an electric field is formed between the cathode assembly and the anode plate 2 (i.e., the electric field force is provided by the high-voltage potential difference); after the air is ionized to form positive and negative charges and adsorbed on the dust surface respectively, the ultrafine dust and the positively charged dust are mainly adsorbed on the dust collecting cathode wire 12, while the negatively charged dust will be adsorbed on the anode plate 2 under the action of the electric field force; in addition, the cathode rapping device 13 can regularly strike the cathode frame 15 to vibrate the RS barbed wire 11 and the dust collecting 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.

[0029] Embodiment 2: See also Figures 7 to 9 The ash absorption structure 122 is an ash absorption hole box. On the one hand, the ash absorption hole box can use the air holes located on the surrounding box walls to allow the positively charged dust particles to enter the box cavity 1221, and on the other hand, it can use the openings located on the bottom box wall to discharge the positively charged dust particles out of the box cavity 1221.

[0030] An air guide plate 123 is also provided in the box cavity 1221, and 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 far away from the air hole; wherein, the air guide plate 123 is threadedly connected to the dust suction hole box through fasteners to facilitate later disassembly and cleaning; the air guide plate 123 can use the air guide cylinder 1231 to effectively prevent the dust in the box cavity 1221 from leaving along the air hole due to the vibration effect and causing secondary dust phenomenon.

[0031] The ash suction hole box is also provided with a plug 1222 extending inwardly at the air hole, and the air guide cylinder 1231 has a socket 1232 for the plug 1222 to be plugged into.

[0032] The rest is the same as in the first embodiment.

[0033] Embodiment three: See also Fig.10 A suction hood 124 with its hood opening facing upward is also provided in the box cavity 1221, and the suction hood 124 is connected to a suction pump through a suction pipe; in addition, a filter can be installed on the suction pipe to prevent dust from entering the suction pump; when in use, whenever the cathode rapping device 13 starts rapping, the suction pump can use the suction hood 124 to suck the hood opening, thereby further preventing the generation of secondary dust.

[0034] The rest is the same as in the second embodiment.

[0035] Embodiment 4: See also Fig.11 The burrs 112 are welded to the surface of a pipe band 113 spirally wound outside the base pipe 111, and the pipe band 113 is threadedly connected to the base pipe 111; during maintenance, workers can separate the pipe band 113 from the base pipe 111, thereby removing all the burrs 112 outside the base pipe 111 at one time.

[0036] The rest is the same as in the first embodiment.

[0037] The above embodiments are intended to illustrate the present invention, not to limit the present invention. Any solution that is a simple transformation of the present invention belongs to the protection scope of the present invention.

Claims

1. An electrostatic precipitator cathode system capable of capturing positively charged dust, characterized in that: The invention comprises an RS small barbed wire (11), a dust collecting cathode wire (12) and a cathode rapping device (13). 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 a tip when a high-voltage power source (4) is powered on. The dust collecting cathode wire (12) is distributed only in 1 to 3 electric fields near an air 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 source (4) is powered on. The cathode rapping device (13) can perform regular rapping on the dust collecting cathode wire (12).

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: The ash absorption structure (122) is an ash absorption mesh plate or an ash absorption hole box. The ash absorption hole box can, on the one hand, utilize the air holes located on the peripheral box wall to allow positively charged dust particles to enter the box cavity (1221), and on the other hand, utilize the openings located on the bottom box wall to discharge the positively charged dust particles out of the box cavity (1221).

4. The electrostatic precipitator cathode system capable of capturing positively charged dust according to claim 3, characterized in that: When the ash suction structure (122) is an ash suction hole box, an air guide plate (123) is further provided in the box cavity (1221), and the air guide plate (123) has an air guide cylinder (1231) arranged directly opposite the air hole, and the inner diameter of the cylinder gradually decreases from a side close to the air hole to a side away from the air hole.

5. The electrostatic precipitator cathode system capable of capturing positively charged dust according to claim 4, characterized in that: The ash suction hole box is also provided with a plug (1222) extending inwardly at the air hole, and the air guide cylinder (1231) has a socket (1232) into which the plug (1222) can be plugged.

6. The electrostatic precipitator cathode system capable of capturing positively charged dust according to claim 5, characterized in that: 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.

7. 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.

8. The electrostatic precipitator cathode system capable of capturing positively charged dust according to claim 7, 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.

9. 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).

10. The electrostatic precipitator cathode system capable of capturing positively charged dust according to any one of claims 1 to 9, 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).

Images