A thermal power plant tail gas electrostatic precipitator

Abstract

The present application relates to the technical field of thermal power generation, and discloses a static dust removal device for processing tail gas of thermal power generation, which comprises a dust removal box, an air inlet channel and an air outlet channel, the cross section of the dust removal box is in a semicircular shape at both ends and a rectangular structure in the middle, the lower surface of both ends of the dust removal box is connected with an ash bucket, and a static dust removal mechanism is arranged in the dust removal box; the static dust removal mechanism comprises two rotating shafts and two groups of transmission wheels, the two groups of transmission wheels are arranged at the upper and lower ends of the two rotating shafts, a closed loop transmission member is arranged between the two horizontally aligned transmission wheels, a plurality of positive plates are connected on the two closed loop transmission members at equal intervals, a negative pole is arranged between two adjacent positive plates, and air blowing dust removal assemblies are arranged at both ends of the dust removal box; the present application has a clever structure design, can clean the dust on the positive plates and negative poles on line during the operation of the static dust removal, and can effectively avoid the damage of the electrodes and plates caused by the vibration device by using high-pressure gas flushing.

Description

Technical Field

[0001] This invention relates to the field of thermal power generation technology, and specifically discloses an electrostatic dust removal device for treating exhaust gas from thermal power plants. Background Technology

[0002] Thermal power generation utilizes the combustion of pulverized coal in a boiler. The heat generated from the combustion of the pulverized coal boils water to produce steam, which is then used to power a steam turbine to generate electricity. The exhaust gases produced during thermal power generation must be treated according to national emission standards before being released into the atmosphere. Electrostatic precipitators, as the core equipment in the treatment of exhaust gases from thermal power plants, use a high-voltage electric field to charge dust particles in the airflow, and then rely on electrostatic adsorption to separate the air from the dust.

[0003] For example, the invention patent with application number 2017113743294 discloses an electrostatic dust removal device, including a housing with an air inlet and an exhaust outlet at both ends, forming a ventilation cavity between the air inlet and the exhaust outlet, and a dust collection trough at the lower end of the housing; a corona generator, disposed in the ventilation cavity, including a sheet-like discharge electrode and a grounding plate; a power supply device, disposed at the top of the housing, for providing high-voltage DC power to the sheet-like discharge electrode; and a rapping device, close to the corona generator, for shaking off the fly ash particles adsorbed on the grounding plate through periodic vibration, and discharging them through the dust collection trough. The electrostatic precipitator disclosed in this patent is a common electrostatic precipitator structure currently on the market. While it has good dust removal effect when used for treating exhaust gas from thermal power plants, this type of precipitator requires disconnecting the power supply and then activating the rapping device to shake off the dust from the electrodes and plates when cleaning dust adhering to the corona generator. Disconnecting the power supply prevents the removal of subsequent incoming dust, thus preventing continuous online dust removal of the exhaust gas. Furthermore, using a vibration device for dust removal not only generates noise but also can damage the electrodes and plates with prolonged vibration. Therefore, to address the above shortcomings of existing electrostatic precipitators, this application proposes an electrostatic precipitator for exhaust gas from thermal power plants that can perform air-blowing cleaning of adhering dust during online dust removal. Summary of the Invention

[0004] The present invention aims to provide an electrostatic dust removal device for thermal power plant exhaust gas that can perform air blowing to remove attached dust during online dust removal, thereby solving the shortcomings of existing electrostatic dust removal devices that require power outage and then use a rapping device to clean the dust from the corona generator.

[0005] This invention is achieved through the following technical solution:

[0006] An electrostatic precipitator for flue gas from thermal power plants includes a dust collection box, an air inlet channel, and an air outlet channel. The dust collection box has a semi-circular cross-section at both ends and a rectangular cross-section in the middle. Ash hoppers are connected to the lower surfaces at both ends of the dust collection box. The air inlet channel and the air outlet channel are respectively connected to the two sides in the middle of the dust collection box. An electrostatic precipitator mechanism is installed inside the dust collection box.

[0007] The electrostatic dust removal mechanism includes two rotating shafts and two sets of transmission wheels. The two rotating shafts are respectively rotatably mounted in dust collection boxes above corresponding ash hoppers, and the dust collection boxes are equipped with power devices connected to the rotating shafts. The two sets of transmission wheels are respectively located at the upper and lower ends of the two rotating shafts. A closed-loop transmission component is provided between the two horizontally aligned transmission wheels. Multiple positive electrode plates are connected at equal intervals on the two closed-loop transmission components. A negative electrode rod connected to the closed-loop transmission component is provided between two adjacent positive electrode plates. Carbon brush assemblies are provided on the top of the positive electrode plates and the negative electrode rods. Two sets of positive and negative copper bars are provided on the top wall of the dust collection box. The positive and negative copper bars are arranged in parallel and connected to the power supply through wires. The carbon brush assemblies on the positive electrode plates are in contact with the positive copper bars, and the carbon brush assemblies on the negative electrode rods are in contact with the negative copper bars.

[0008] Both ends of the dust collection box are equipped with air-blowing dust removal components, and the air-blowing dust removal components are positioned facing the positive electrode plate and negative electrode rod at the end of the closed-loop transmission component.

[0009] In the electrostatic precipitator for flue gas from thermal power plants disclosed in this invention, during operation, both the positive electrode plate and the negative electrode rod are in contact with the positive and negative copper bars respectively through the carbon brush assembly at the top, thereby generating a high-voltage electric field between them. After preliminary treatment, the flue gas in the boiler enters the dust collection box. When flowing through the electric field, the dust particles become charged, and the air and dust are separated by electrostatic adsorption, with the dust adhering to the positive electrode plate.

[0010] In this invention, the electrostatic dust removal mechanism will start the power unit once after running for a period of time, so that the closed-loop transmission component moves a certain distance in the dust removal box, thereby moving the positive electrode plate with a large amount of dust on its surface to the top of the ash hopper and aligning it with the air blowing dust removal component. At this time, the other positive electrode plates and negative electrode rods will also move to replace the previous positive electrode plates and negative electrode rods and be put into electrostatic dust removal. There will be no disappearance of the dust removal electric field in the middle.

[0011] Subsequently, the air-blowing dust removal component is activated, using the high-pressure airflow to act on the positive and negative electrode plates directly above the ash hopper, causing the attached dust to be blown off and finally discharged into the ash hopper. The entire electrostatic precipitator for thermal power plant exhaust gas can disconnect the positive and negative electrode plates and rods to be treated online during the electrostatic precipitation process, while other positive and negative electrode plates and rods will take their place, preventing the disappearance of the dust removal electric field and achieving online air-blowing cleaning of the positive and negative electrode plates and rods.

[0012] As a further feature of the above scheme, multiple dust collection boxes are arranged side by side, and adjacent dust collection boxes are connected by a flow channel. The air inlet channel and the exhaust channel are respectively connected to the outer surfaces of the two outermost dust collection boxes. Through the interconnected design of the multiple dust collection boxes, each electrostatic precipitator acts as a step in the electrostatic precipitator process, and the dust in the exhaust gas of thermal power generation can be fully removed through continuous electrostatic precipitator action.

[0013] As a further feature of the above scheme, a conductive rod is connected to the upper end of the positive electrode plate, and the carbon brush assembly is connected to the positive electrode plate through the conductive rod.

[0014] As a further provision of the above solution, the carbon brush assembly includes an outer shell with a mounting groove. An inner shell extends into the mounting groove via an elastic element. A carbon brush block extending from the mounting groove is disposed within the inner shell, and the inner end of the carbon brush block is connected to a conductive rod or a negative electrode rod. Through this structural design of the carbon brush assembly, the carbon brush block can always maintain close contact with the positive or negative electrode copper strip under the support of the elastic element.

[0015] As a further feature of the above scheme, the top wall of the dust collector is provided with an insulating plate, and both the positive and negative copper bars are mounted on the insulating plate, with the lengths of the positive and negative copper bars being equal to the length of the straight side of the closed-loop transmission component.

[0016] As a further feature of the above scheme, both the positive electrode plate and the negative electrode rod are fixedly connected to the closed-loop transmission component through insulating connectors.

[0017] As a further feature of the above solution, the air blowing dust removal assembly includes a compressed air source, a compressed air pipe connected to the compressed air source and arranged parallel to the end of the dust removal box, a row of nozzles extending into the dust removal box connected to the compressed air pipe, and a solenoid valve provided at the end of the compressed air pipe near the compressed air source.

[0018] As a further feature of the above scheme, the ash hopper is provided with a rotating bracket connected to the lower end of the rotating shaft.

[0019] As a further feature of the above scheme, the negative electrode rod is provided with a plurality of discharge tips facing the positive electrode plate.

[0020] Compared with the prior art, the present invention has at least the following beneficial effects:

[0021] The electrostatic precipitator for thermal power plant exhaust gas disclosed in this invention uses a closed-loop transmission component to drive the positive electrode plate and negative electrode rod to circulate within the dust collection box. Through the contact between the carbon brush assembly and the positive and negative copper bars, both the positive electrode plate and negative electrode rod at both ends of the closed-loop transmission component can be used in the electrostatic precipitator process. The positive electrode plate and negative electrode rod at both ends are then subjected to high-pressure gas scouring by the air-blowing dust removal component, which efficiently removes the attached dust. The entire electrostatic precipitator for thermal power plant exhaust gas has an ingenious structural design, which not only cleans the dust on the positive electrode plate and negative electrode rod online during electrostatic precipitator operation, but also effectively avoids the shortcomings of using vibration devices that are prone to damage to the electrodes and plates by using high-pressure gas scouring.

[0022] The present invention further improves the design by connecting multiple dust collection boxes with the same structure side by side, so that the exhaust gas from thermal power generation can pass through the high-voltage electric field of electrostatic dust removal multiple times. In this way, the dust in the exhaust gas from thermal power generation can be fully removed through the action of continuous electrostatic dust removal, thus ensuring the treatment effect of the exhaust gas. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0025] Figure 2 This is a schematic diagram of the internal planar structure of the present invention from the front view.

[0026] Figure 3 This is a top view of the internal planar structure of the present invention;

[0027] Figure 4 This is a three-dimensional structural diagram of the electrostatic dust removal mechanism, positive and negative copper bars, etc., in this invention;

[0028] Figure 5 This is a bottom-view three-dimensional structural diagram of the electrostatic dust removal mechanism in this invention;

[0029] Figure 6 This is a three-dimensional structural schematic diagram of Embodiment 2 of the present invention;

[0030] Figure 7 This is a schematic diagram of the internal planar structure of the carbon brush assembly in this invention. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0032] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The following will refer to the appendix... Figures 1-7 This application will be described in detail with reference to the embodiments. Example 1

[0033] Example 1 discloses an electrostatic precipitator for flue gas from thermal power plants, as shown in the attached figure. Figure 1 Appendix Figure 2 and attached Figure 3 The main body includes a dust collection box 1 and an air-blowing dust removal assembly 2. The horizontal cross-section of the dust collection box 1 has an oblong, perforated structure, with semi-circular front and rear ends and a rectangular middle section. Dust hoppers 3 are connected to the lower surfaces of both the front and rear ends of the dust collection box 1. An air inlet channel 4 is provided at the center of the left side of the dust collection box 1, and an exhaust channel 5 is provided at the center of the right side of the dust collection box 1. An electrostatic dust removal mechanism 6 is provided inside the dust collection box 1.

[0034] Reference Appendix Figure 4 and attached Figure 5 The electrostatic dust removal mechanism 6 includes two rotating shafts 601 and two sets of transmission wheels 602. The two rotating shafts 601 are concentrically arranged in the dust collection box 1 above the corresponding ash hopper 3. A rotating bracket 301 connected to the lower end of each rotating shaft 601 is installed in the ash hopper 3. The upper ends of the two rotating shafts 601 are rotatably connected to the upper surface of the dust collection box 1. The two sets of transmission wheels 602 are respectively located at the upper and lower ends of the corresponding rotating shafts 601. A closed-loop transmission component 603 is arranged between the two transmission wheels 602 aligned horizontally on the two rotating shafts 601. A power unit 604 connected to one of the rotating shafts 601 is also installed on the upper surface of the dust collection box 1. In specific configurations, the transmission wheels 602 are preferably pulleys, the closed-loop transmission component 603 is a transmission belt, and the power unit 604 is a combination of a motor and a reducer.

[0035] Multiple positive electrode plates 605 are fixedly connected at equal intervals to the outer surfaces of the upper and lower closed-loop transmission components 603. To prevent charge transfer between the positive electrode plates 605 and the closed-loop transmission components 603, multiple insulating connectors are evenly arranged on the closed-loop transmission components 603, thereby achieving a fixed connection between the positive electrode plates 605 and the closed-loop transmission components 603. A negative electrode rod 606 is arranged between two adjacent positive electrode plates 605. The negative electrode rod 606 is also fixedly connected to the closed-loop transmission component 603 through insulating connectors, allowing the positive electrode plates 605 and the negative electrode rod 606 to circulate and move within the dust collection box 1 along with the closed-loop transmission components 603. In addition, to improve the discharge effect and enhance the electrostatic dust removal capability of the electrostatic field, multiple discharge tips facing the positive electrode plate side 605 are also provided on the negative electrode rod 606.

[0036] A conductive rod 607 is connected to the upper end of each positive electrode plate 605. A carbon brush assembly 608 is installed on the top of both the conductive rod 607 and the negative electrode rod 606. The carbon brush assemblies 608 on the conductive rod 607 and the negative electrode rod 606 are staggered along the trajectory of the closed-loop transmission component 603. An insulating plate 7 is fixed to the top wall of the dust collector 1. A positive copper strip 701 and a negative copper strip 702, arranged parallel to each other, are installed on the lower surface of the insulating plate 7 at both ends. The positive copper strip 701 and the negative copper strip 702 are connected to an external power source via wires. Meanwhile, the lengths of the positive copper strip 701 and the negative copper strip 702 are equal to the length of the straight side of the closed-loop transmission component 603. The positive copper strip 701 is positioned above the moving path of the conductive rod 607, and the negative copper strip 702 is positioned above the moving path of the negative rod 606. This ensures that during the linear movement of the positive plate 605 and the negative rod 606, both come into contact with the positive copper strip 701 and the negative copper strip 702 through the top carbon brush assembly 608, thereby generating an electric field between the positive plate 605 and the negative rod 606.

[0037] Reference Appendix Figure 7To ensure stable contact between the carbon brush assembly 608 at the top of the positive electrode plate 605 or the negative electrode rod 606 and the positive electrode copper strip 701 or the negative electrode copper strip 702, the carbon brush assembly 608 in this embodiment includes a housing 6081. A mounting groove 6082 is provided inside the housing 6081. An inner housing 6084 is connected to the mounting groove 6082 via an elastic element 6083. A carbon brush block 6085 protrudes from the mounting groove 6082 within the inner housing 6084, and the inner end of the carbon brush block 6085 is connected to the positive electrode plate 605 or the negative electrode rod 606 via the inner housing 6084 and the outer housing 6081. Furthermore, both the inner housing 6084 and the outer housing 6081 in this embodiment are made of insulating material. The carbon brush assembly 608 described above ensures that the carbon brush block 6085 is always in close contact with the positive copper strip 701 and the negative copper strip 702. Even after the carbon brush block 6085 has worn down to a certain extent, it can still be in close contact with the positive copper strip 701 and the negative copper strip 702 under the action of the elastic element 6083.

[0038] Final reference appendix Figure 1 Appendix Figure 2 and attached Figure 3 In this embodiment, the air-blowing dust removal assembly 2 includes a compressed air source 201 fixed to the outer surface of the dust collection box 1. The compressed air source can be a compressed air tank or an air compressor. A compressed air pipe 202 is connected to the compressed air source 201 and is arranged parallel to both ends of the dust collection box 1. A solenoid valve is arranged at the position of the compressed air cylinder 202 near the compressed air source 201. The solenoid valve controls the opening and closing of the gas in the compressed air pipe 202. Finally, a row of nozzles 203 are connected to the compressed air pipe 202 and are arranged to extend into the dust collection box 1. The nozzles 203 are arranged facing the positive electrode plate 605 and the negative electrode rod 606 at the end of the closed-loop transmission component 603. Example 2

[0039] Example 2 discloses an electrostatic dust removal device for thermal power plant exhaust gas that is an improved design based on the technical solution in Example 1. The similarities between Example 2 and Example 1 will not be described again.

[0040] Reference Appendix Figure 6 The electrostatic precipitator for thermal power plant exhaust gas disclosed in Embodiment 2 includes at least two dust collection boxes 1 arranged side by side. In this figure, there are a total of three dust collection boxes 1, and a flow channel 8 is connected between two adjacent dust collection boxes 1. An air inlet channel 4 and an exhaust channel 5 are respectively provided on the outer side of the two outermost dust collection boxes 1. Then, a corresponding electrostatic precipitator 6 is provided inside each dust collection box 1. At the same time, a corresponding air blowing dust removal component 2 is also provided on each dust collection box 1 to perform online air blowing cleaning of the electrostatic precipitator 6. The dust discharged after cleaning falls into the ash hopper 3 below the corresponding dust collection box 1.

[0041] This embodiment 2, through the design of multiple sets of electrostatic dust removal mechanisms 6, can perform multiple electrostatic dust removal treatments on the exhaust gas of thermal power generation, thereby improving the dust removal effect on the exhaust gas of thermal power generation.

[0042] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An electrostatic precipitator for flue gas from thermal power plants, comprising a dust collection box, an air inlet channel, and an air outlet channel, characterized in that, The dust collector has a semi-circular cross-section at both ends and a rectangular cross-section in the middle. The lower surfaces at both ends of the dust collector are connected to ash hoppers. The air passage and the air outlet passage are respectively connected to the two sides in the middle of the dust collector. An electrostatic dust removal mechanism is installed inside the dust collector. The electrostatic dust removal mechanism includes two rotating shafts and two sets of transmission wheels. The two rotating shafts are respectively rotatably mounted in dust collection boxes above corresponding ash hoppers, and the dust collection boxes are equipped with power devices connected to the rotating shafts. The two sets of transmission wheels are respectively located at the upper and lower ends of the two rotating shafts. A closed-loop transmission component is provided between the two horizontally aligned transmission wheels. Multiple positive electrode plates are connected at equal intervals on the two closed-loop transmission components. A negative electrode rod connected to the closed-loop transmission component is provided between two adjacent positive electrode plates. Carbon brush assemblies are provided on the top of the positive electrode plates and the negative electrode rods. Two sets of positive and negative copper bars are provided on the top wall of the dust collection box. The positive and negative copper bars are arranged in parallel and connected to the power supply through wires. The carbon brush assemblies on the positive electrode plates are in contact with the positive copper bars, and the carbon brush assemblies on the negative electrode rods are in contact with the negative copper bars. Both ends of the dust collection box are equipped with air-blowing dust removal components, and the air-blowing dust removal components are positioned facing the positive electrode plate and negative electrode rod at the end of the closed-loop transmission component.

2. The electrostatic precipitator for flue gas from thermal power plants according to claim 1, characterized in that, Multiple dust collection boxes are arranged side by side, and adjacent dust collection boxes are connected by a flow channel. The air inlet channel and the air outlet channel are respectively connected to the outer side of the two outermost dust collection boxes.

3. The electrostatic precipitator for flue gas from thermal power plants according to claim 1 or 2, characterized in that, A conductive rod is connected to the upper end of the positive electrode plate, and the carbon brush assembly is connected to the positive electrode plate through the conductive rod.

4. The electrostatic precipitator for flue gas from thermal power plants according to claim 3, characterized in that, The carbon brush assembly includes an outer shell with a mounting groove. An inner shell extends out of the mounting groove via an elastic element. A carbon brush block extends out of the mounting groove and is disposed in the inner shell. The inner end of the carbon brush block is connected to a conductive rod or a negative electrode rod.

5. The electrostatic precipitator for flue gas from thermal power plants according to claim 1 or 2, characterized in that, The top wall of the dust collector is provided with an insulating plate, and the positive and negative copper bars are both set on the insulating plate, with the lengths of the positive and negative copper bars being equal to the length of the straight side of the closed-loop transmission component.

6. The electrostatic precipitator for flue gas from thermal power plants according to claim 1 or 2, characterized in that, Both the positive electrode plate and the negative electrode rod are fixedly connected to the closed-loop transmission component via insulating connectors.

7. The electrostatic precipitator for flue gas from thermal power plants according to claim 1 or 2, characterized in that, The air-blowing dust removal assembly includes a compressed air source, a compressed air pipe connected to the compressed air source and arranged parallel to the end of the dust removal box, a row of nozzles extending into the dust removal box connected to the compressed air pipe, and a solenoid valve provided at the end of the compressed air pipe near the compressed air source.

8. The electrostatic precipitator for flue gas from thermal power plants according to claim 1 or 2, characterized in that, The ash hopper is equipped with a rotating bracket connected to the lower end of the rotating shaft.

9. The electrostatic precipitator for flue gas from thermal power plants according to claim 1 or 2, characterized in that, The negative electrode rod is provided with multiple discharge tips facing the positive electrode plate.

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