Magnetization-enhanced fine dust electrostatic precipitator

Abstract

The application discloses a kind of fine dust magnetization enhancement electrostatic precipitator, belong to fine dust purification dust removal technical field.The whole is vertical cylinder structure, including dust remover shell, external magnetized water preparation system, high-pressure water mist generator, high-voltage direct-current electrostatic generator and dust collection inner cone device.Utilize neodymium iron boron rare earth permanent magnet to build multiple wave peak vertical central magnetic field, magnetization intensity 300mT~350mT, water flow is cut magnetic field with not less than 1.5~3m / s flow rate to realize water body magnetization;Magnetized water is atomized by the spiral nozzle arranged in annular at top, cooperate 15~40kV high-voltage direct-current electrostatic field, make water mist and dust bidirectional charging, improve dust specific resistance and strengthen fine dust coagulation;Dust collection inner cone device of specific size is set at the bottom of dust remover to collect dust.Can efficiently capture PM2.5 fine particulate matter, suitable for industrial and mining workshop, mine and city fine dust treatment, equipment structure is compact, stable operation, effectively reduce the secondary pollution risk brought by wet dust removal, with broad application prospect.

Description

Technical Field

[0001] This invention belongs to the technical field of air pollution control and dust removal equipment, specifically involving a dust removal device that uses magnetized water in conjunction with high-voltage electrostatic enhancement to capture fine dust. It is mainly used for fine dust control in mine working faces and industrial production workshops, and can also be used for the purification of PM2.5 fine particulate matter in urban exhaust gas. It is suitable for efficient dust removal operations under high concentration of fine dust conditions. Background Technology

[0002] Wet spray dust suppression systems are widely used in industrial and mining dust control due to their simple structure, low construction cost, and convenient operation and maintenance. Conventional wet spray dust suppression systems typically use ordinary tap water directly, which has low supply pressure, high surface tension, limited wetting ability, and relatively large atomized particle size, thus limiting dust suppression effectiveness. The overall dust reduction efficiency of existing conventional wet spray dust suppression systems is only 50%–60%, and for PM2.5 fine dust particles that are extremely difficult to capture due to their small size and high suspension, the capture efficiency is only 20%–30%, which is insufficient to meet increasingly stringent occupational health standards and ultra-low emission requirements. Therefore, improving the capture efficiency of PM2.5 fine dust is of significant engineering value for the control of fine dust pollution in mines, industrial workshops, and cities.

[0003] Existing magnetoelectric dust removal technologies have been publicly reported. CN1706555A discloses a magnetoelectric dust filter, the principle of which is that dust becomes charged under the combined action of a magnetic field and an electric field, and the charged dust is separated through an electrostatic filter electrode. The charged electric field is constructed by barbed electrodes and plate electrodes. However, this scheme does not modify or optimize the spray medium and lacks a water mist wetting and agglomeration mechanism, thus having limited ability to handle ultrafine dust. CN110237931A discloses a magnetoelectric composite gas purifier, which can identify the charged state of aerosol particles and match the corresponding collection strategy. However, the entire device requires a particle charge detection and control system, which is complex in structure, large in size, and has high energy consumption, making it difficult to adapt to the high-flow continuous dust removal conditions in mines and factories. CN201911050425.2 discloses a suspended cloud dust removal and purification device based on magnetoelectric coupling, which uses magnetized spray to promote dust agglomeration. It belongs to the category of traditional wet dust removal and is prone to generating wastewater and sludge during operation, resulting in significant secondary pollution problems.

[0004] Most of the existing technologies mentioned above rely solely on the direct action of electric and magnetic fields on dust, or simply employ magnetized water mist wet dust removal, lacking a synergistic design that combines magnetized water modification, electrostatic charge, and structural optimization. Simple magnetized water mist dust removal still results in secondary pollution from waste liquid, while conventional electrostatic dust removal suffers from drawbacks such as unsuitable resistivity of fine dust and poor agglomeration effects. Therefore, there is an urgent need to develop a novel device that utilizes magnetized water humidification to regulate dust resistivity, simultaneously enhancing the agglomeration effect of fine dust, and combining this with a high-voltage electrostatic field to achieve efficient removal of PM2.5 fine dust, thus mitigating the secondary pollution problems associated with wet dust removal. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies, such as the low removal efficiency of conventional wet dust removal for PM2.5 fine dust, the tendency of traditional magnetized cloud dust removal to generate secondary pollution, and the complex structure of magneto-electrostatic dust removal, and to provide a magnetized enhanced electrostatic precipitator for fine dust. This invention uses an external magnetized water preparation system to magnetize and modify the water body, combined with high-pressure atomizing nozzles arranged in a ring at the top of the cylinder to generate activated magnetized water mist. Coupled with a 15-40kV high-voltage DC electrostatic field, the water mist particles collide with the fine dust particles, causing bidirectional charging. The magnetized water mist improves wetting ability and adjusts the dust resistivity, promoting the agglomeration and growth of fine dust particles. Combined with the optimized dust collection cone at the bottom, this achieves efficient dust collection, significantly improving the PM2.5 fine dust capture efficiency.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A magnetized enhanced electrostatic precipitator for fine dust, the overall structure of which is a vertical cylindrical body, mainly composed of a dust collector shell, an external magnetized water preparation system, a high-pressure water mist generator, a high-voltage DC electrostatic generator, and a dust collection inner cone device. The external magnetized water preparation system is arranged outside the dust collector shell, and uses neodymium iron boron rare earth permanent magnet material to construct a multi-peak vertical central magnetic field; when the magnetization intensity is 300mT~350mT and the water flows through the vertical magnetic field at a high speed of 1.5~3m / s, an induced electromotive force is generated inside the water flow, the water molecule cluster structure changes, the surface tension of the water decreases, and the wetting and atomization performance is improved, thus completing the magnetization modification of the water.

[0007] The high-pressure water mist generator includes an oil-free air compressor and spiral nozzles. The spiral nozzles are evenly distributed in a ring and installed at the top of the dust collector housing. The number of nozzles is set to 16 to 24, and the atomization liquid-to-gas ratio is 100 to 200 ml / m³. 3The working pressure is maintained at 2–5 Bar. The magnetized water is transported to each spiral nozzle through a water supply pipe, where it is atomized to form a large number of highly active magnetized water mist particles. A high-voltage DC electrostatic generator is connected to an electrostatic electret rod, creating a 15–40 kV high-voltage electrostatic field within the dust collector cavity. Dust-laden gas enters the cylinder from bottom to top, and the fine dust particles come into full contact with the magnetized water mist. Under the influence of the electrostatic field, the dust particles and water mist particles collide and become charged. The magnetized water mist improves the wetting performance and simultaneously regulates the dust resistivity, promoting the agglomeration of tiny dust particles into larger dust droplet clusters.

[0008] A dust-collecting inner cone device is installed in the ash hopper area at the bottom of the dust collector. The cone apex angle is controlled between 70° and 90°, and the distance between the outer wall of the inner cone and the inner wall of the dust collector shell is set to 10-15 mm to optimize airflow distribution and reduce secondary re-entrainment of fine dust. The shell is equipped with a rapping cleaning mechanism. When dust accumulates to a certain thickness on the collecting electrode, the rapping mechanism causes the dust layer to fall off, and the dust settles into the ash hopper by gravity for collection. The purified gas is discharged outward from the exhaust port at the top of the cylinder.

[0009] The magnetization intensity of the magnetized water preparation system of this invention can be adjusted in the range of 300mT to 350mT, and the output voltage of the high-voltage DC electrostatic generator can be adjusted according to the dust conditions to meet the exhaust gas purification needs of different dust concentrations and particle size distributions. Attached Figure Description

[0010] Figure 1 is a schematic diagram of the overall structure of a magnetized enhanced electrostatic precipitator for fine dust according to the present invention; Reference numerals: 1 - precipitator shell, 2 - external magnetized water preparation system, 3 - water supply pipe, 4 - oil-free air compressor, 5 - spiral nozzle, 6 - high-voltage DC electrostatic generator, 7 - electrostatic electret rod, 8 - rapping cleaning mechanism, 9 - dust collection inner cone device, 10 - ash hopper, 11 - dust-laden gas inlet, 12 - purified gas exhaust port. Detailed Implementation

[0011] The present invention will now be described in more detail with reference to the accompanying drawings and embodiments.

[0012] As shown in Figure 1, this invention is a vertical cylindrical structure. A dust-laden gas inlet (11) is opened on the lower side wall of the dust collector shell (1), and a purified gas exhaust port (12) is set at the upper end of the cylinder. An external magnetized water preparation system (2) is independently arranged on the outside of the shell. The water source is connected to the external magnetized water preparation system, and the water flows at high speed through the vertical magnetic field constructed by the permanent magnet to complete magnetization; the magnetized water is transported via a water supply pipe (3) to a spiral nozzle (5) arranged in a ring at the top of the shell. An oil-free air compressor (4) is connected to the spiral nozzle to provide atomized air. An electrostatic electret rod (7) is vertically installed along the axis of the shell, and the electrostatic electret rod is electrically connected to a high-voltage DC electrostatic generator (6) on the outside of the shell. A rapping dust removal mechanism (8) is installed on the shell; a dust hopper (10) is connected to the bottom of the shell, and a dust collection cone device (9) is installed inside the dust hopper.

[0013] Workflow: Dust-laden exhaust gas enters the dust collector cavity from bottom to top through the dust-laden gas inlet (11); water enters the external magnetized water preparation system (2), with the water flow velocity maintained at 1.5~3m / s, achieving magnetization modification under the action of a multi-peak vertical magnetic field; the magnetized water is transported to the spiral nozzle (5), with a liquid-to-gas ratio of 100~200ml / m 3 Atomization at 2-5 Bar pressure forms magnetized water mist; the high-voltage DC electrostatic generator (6) is started, and an electrostatic field of 15-40kV is formed in the inner cavity. Fine dust comes into contact with the magnetized water mist, gets wet and becomes charged. The magnetized water improves the wetting performance and optimizes the dust resistivity, causing PM2.5 fine dust to collide and agglomerate and grow. The agglomerated dust clumps settle downward under the action of gravity and adhere to the dust collection area. The rapping and dust removal mechanism (8) rappels periodically, and the dust falls into the dust hopper (10). The dust collection inner cone device (9) stabilizes the flow field and suppresses the secondary re-flying of dust. The purified gas flows upward and is discharged through the purified gas exhaust port (12).

[0014] Example 1: Magnetization intensity set at 350mT, high-voltage electrostatic output voltage at 35.0kV; number of spiral nozzles at 20, liquid-to-gas ratio at 120ml / m³. 3 The atomization pressure is 3 Bar, and the magnetized water flow rate is 1.6 m / s. The total dust reduction efficiency of conventional water-based wet dust removal is 55.7%; the total dust reduction efficiency of this device reaches 94.8%, which is 70.2% higher than that of water-based dust removal; compared with simple magnetized water mist wet dust removal, the total dust reduction efficiency is increased by 32.5%, and the removal effect of PM2.5 fine dust is significantly improved.

[0015] Example 2: Magnetization intensity set at 300 mT, charging voltage at 30 kV; liquid-to-gas ratio at 140 ml / m³. 3The atomization pressure was 2.5 Bar, and the magnetized water flow rate was 1.5 m / s. The test results showed that the overall dust reduction efficiency of the device was 92.8%, which is 66.6% higher than that of wet dust removal with clean water; compared with magnetized water mist dust removal alone, the overall dust reduction efficiency was 34.1% higher. It is suitable for continuous treatment of fine dust with conventional concentrations and has a lower energy consumption level.

[0016] Example 3: Magnetization intensity 320mT, charging voltage 36kV; liquid-to-gas ratio 120ml / m³ 3 The atomization pressure is 3.5 Bar, and the magnetized water flow rate is 1.55 m / s. Under operating conditions, the total dust removal efficiency is 93.9%, which is 68.6% higher than wet dust removal with clean water and 33.8% higher than simple magnetized water mist dust removal. It is suitable for harsh operating conditions with high concentrations of PM2.5 fine dust.

[0017] Compared with existing technologies, this invention has the following outstanding advantages: First, this invention innovatively adopts an external magnetized water preparation system, utilizing neodymium iron boron permanent magnets to generate a multi-peak vertical magnetic field. After high-speed water flow is magnetized and modified, it forms a highly active water mist, enhancing the water mist's ability to wet fine dust and strengthening the PM2.5 coagulation effect. Simultaneously, it regulates the dust resistivity, solving the problem of unsuitable resistivity in fine electrostatic dust removal. Second, the magnetized water mist atomization system is arranged at the top of the cylinder, combined with a vertical bottom-up air intake method, extending the contact time between the water mist and dust. Coupled with a 15-40kV high-voltage electrostatic field, the effect is significantly better than single magnetized spray dust removal. Third, a dust collection inner cone device with optimized structural parameters is set at the bottom, with a cone apex angle of 70°-90° and a shell gap of 10-15mm, stabilizing the internal airflow field, effectively suppressing secondary re-entrainment of settled dust, and further improving the collection efficiency of fine dust. Fourth, unlike traditional magnetized wet dust removal, this device relies on magnetized wetting and condensation combined with high-voltage electrostatic precipitators to capture dust, significantly reducing the amount of spray water and producing no wastewater or sludge, thus alleviating the secondary pollution problems of traditional wet electrostatic precipitators. Fifth, the device's operating conditions are adjustable; the magnetization intensity and electrostatic voltage can be adjusted according to dust conditions, adapting to various working conditions such as mines, industrial workshops, and urban waste gas. Comparative tests have shown that under optimal operating conditions, the total dust removal efficiency can reach 94.8%, exhibiting excellent removal effects on PM2.5 fine particulate matter, stable operation, and good prospects for industrial application.

Claims

1. A magnetized enhanced electrostatic precipitator for fine dust, characterized in that: The overall structure is a vertical cylindrical structure, including a dust collector shell, an external magnetized water preparation system, a high-pressure water mist generator, a high-pressure DC electrostatic generator, and a dust collection inner cone device; The external magnetized water preparation system uses neodymium iron boron rare earth permanent magnet material to construct a multi-peak vertical central magnetic field. Water flows through the magnetic field at a flow rate of 1.5 to 3 m / s to achieve magnetization modification. The working magnetization intensity of the magnetized water preparation system is adjustable, with an adjustment range of 300 mT to 350 mT.

2. The magnetized enhanced fine dust electrostatic precipitator according to claim 1, characterized in that: The external magnetized water preparation system is independently located outside the dust collector housing. Magnetized water is transported to each spiral nozzle via a water supply pipe. The spiral nozzles of the high-pressure water mist generator are arranged in a ring at the top of the dust collector housing, numbering 16–24. The atomization pressure is controlled at 2–5 Bar, and the liquid-to-gas ratio is 100–200 ml / m³. 3 .

3. The magnetized enhanced fine dust electrostatic precipitator according to claim 1, characterized in that: The high-voltage DC electrostatic generator is connected to an electret rod, forming a 15-40kV electrostatic field inside the casing, with an electric field wind speed of 0.5-1m / s.

4. The magnetized enhanced fine dust electrostatic precipitator according to claim 1, characterized in that: The dust collection inner cone device is installed inside the bottom ash hopper, with a cone apex angle of 70° to 90°, and a gap of 10 to 15 mm is maintained between the outer wall of the dust collection inner cone and the dust collector shell.

5. The magnetized enhanced fine dust electrostatic precipitator according to claim 1, characterized in that: The dust collector shell is equipped with a rapping cleaning mechanism. The dust generated by the rapping falls into the bottom ash hopper and the inner cone area of ​​the dust collection by gravity. The dust-laden airflow flows from bottom to top through the mixing area of ​​electrostatic field and magnetized water mist. The fine dust collides with the magnetized water mist, becomes charged, condenses and grows. The purified gas is discharged from the exhaust port at the top of the cylinder.

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