CN108079696A - A kind of device for removing conductive dust, method and application thereof - Google Patents

Abstract

The invention relates to a device, method and application for removing conductive dust. The device includes a clean air chamber and a dust removal chamber separated from each other by flower plates; the dust removal chamber is provided with a porous metal filter tube; the porous metal filter The bottom end of the tube is sealed, and the flange and the insulating gasket under the flange realize gas sealing and electrical insulation between the top end and the flower plate; The outside of the metal filter tube is coated with an insulating coating; the porous metal filter tube is charged by an external high-voltage power supply. This device has the advantages of high temperature resistance, good strength, and weldability of the porous metal filter tube, and it is easy to clean the dust. The air resistance rises slowly with the thickness of the powder cake. It is a high-efficiency dust removal with low air resistance and high flux. Device; the insulation coating solves the insulation between the porous metal filter tube and the dust removal slide, improves the dust removal efficiency and safety, and is very suitable for the removal and collection of conductive dust in a non-corrosive atmosphere.

Description

A device, method and application for removing conductive dust

technical field

The invention relates to the technical field of nonferrous metallurgy, in particular to a device, method and application for removing conductive dust.

Background technique

In the field of non-ferrous metallurgy, there are many industrial needs that need to remove conductive dust at high temperature, such as spraying aluminum industry under nitrogen to prepare ultra-fine aluminum powder, converter copper smelting, etc. Reliable technology that can withstand high temperatures and adequately remove dust is urgently needed in these applications. In addition, due to the high added value of dust, the effect of dust removal must be stable and reliable.

At present, there are many mature technologies in the field of industrial dust removal, such as: mechanical dust removal, wet dust removal, bag dust removal, electrostatic dust removal and electrostatic bag composite dust removal and so on. Mechanical dedusting is a method of dust removal using dust chambers, cyclone separators and other mechanical devices. Wet dedusting is a method of dedusting using spray towers, water film dust collectors or Venturi dust collectors. It is often used to deal with large dust particles. Gas, for the occasions where fine particles need to be removed and the gas temperature is high, both mechanical dust removal and wet dust removal are difficult to do.

The dust removal efficiency of the bag type dust collector is very high, and it has good tolerance to the fluctuation of the particle size range of the dust. Even fine dust can successfully obtain a high retention rate. However, the pressure drop of the bag type dust collector is relatively large. The dynamic load requirements of gas transmission equipment are high. In addition, the common cloth bags are difficult to withstand high temperature. For the sintering flue gas containing red hot particles and ignition particles in the waste gas, "burning bag" accidents often occur when using cloth bag dust removal. In addition, in the common industrial waste gas treatment section, the pressure of the waste gas is very low. For the bag type dust collector with a large pressure drop, it is often necessary to increase the pressure head of the fan to cope with the pressure drop of the bag, and even need to purchase a new fan. In an industrial device that produces ultra-fine aluminum powder by spraying, bag dust collection is the only way to obtain the product aluminum powder. However, with the ultra-fine aluminum powder, the resistance of the powder cake rises rapidly, and the bag needs to be regenerated frequently .

Electrostatic precipitator is also a very common and efficient dust removal method at present. This method is to first charge the dust in the gas, and then remove it from the air flow by electric field force and fix it on the surface of the electrode plate. This method can be used for high-temperature exhaust gas treatment, and has only a small pressure drop resistance, but its disadvantage is that it has certain requirements on the conductivity of the dust and the humidity of the gas. Even if the conductive powder falls on the dust collecting plate, it will quickly It loses charge and reloads the opposite charge, and then is ejected from the dust collecting plate, so electric dust removal cannot remove conductive dust. In addition, the corona electrode of electrostatic precipitator works under the condition of frequent sparks, so when the atmosphere contains oxygen, there is a potential danger of dust explosion. In addition, whether the electrostatic precipitator can successfully charge is closely related to the composition of the gas. For the case where the gas composition is mainly nitrogen and the oxygen content is very small, the electrostatic precipitator cannot effectively charge the dust.

At present, the preparation of porous metal filter tubes formed by pressing metal powder is very mature. China Iron and Steel Technology Group Co., Ltd. already has the large-scale production capacity of porous metal filter plates and filter tubes. The filter tubes produced are used in coal gasification, coal liquefaction, Industrial applications have been achieved in the fields of non-ferrous metallurgy and high-temperature dust removal. This type of porous metal filter tube has many advantages such as good strength, not easy to break, and can be welded, but its disadvantages are also obvious. First, the filter tube is a homogeneous material, and it is difficult to obtain a gradient Pores, so fine dust is easy to drill into the inside of the pipe body and cause blockage. Second, the pressure drop of the filter pipe is relatively large, especially when filtering fine dust. When containing corrosive components, metal pipes often cause plugging due to corrosion.

Our research team has used the surface conductive ceramic filter tube as the filter medium to develop a dust removal method for conductive dust and disclosed it in CN105149092A. Voltage, when the conductive dust reaches the surface of the conductive ceramic tube, the dust will be charged by the conductive ceramic tube, and the charged conductive dust will form a loose powder cake on the surface of the ceramic tube due to the electrostatic repulsion, thereby greatly reducing the filter pressure of the powder cake drop. However, the practice of this technical solution also encountered certain operational difficulties. First, the conductive ceramic tube is brittle, and its length cannot exceed 2m, resulting in a large area occupied by the dust collector; second, the conductive ceramic tube has poor strength and is not resistant to bumps. The process has caused great difficulties; third, because the lead-in line of the external high-voltage power supply is on the side of the dust collector containing conductive dust, it is easy to deposit conductive dust on the wall-penetrating porcelain parts, resulting in high-voltage and grounded equipment shells conduction, and then an electrical breakdown accident occurs.

Contents of the invention

In view of the problems existing in the prior art, one of the objectives of the present invention is to provide a dust removal method for conductive dust, and obtain a high-efficiency dust removal device with low air resistance and high flux through a simple method. The device has the advantages of high strength, not easy to break, and weldable porous metal filter tube, and it is easy to clean the dust, and the air resistance increases slowly with the thickness of the powder cake.

For reaching this purpose, the present invention adopts following technical scheme:

In the first aspect, the present invention provides a device for removing conductive dust, a clean air room and a dust removal room separated from each other by flower plates; a porous metal filter tube is arranged in the dust removal room; the bottom end of the porous metal filter tube is sealed , between the top end and the flower plate, gas sealing and electrical insulation are realized through the flange and the insulating gasket under the flange; the outside of the flange and the outside of the porous metal filter tube 10-20 cm below the flange are both Coated with an insulating coating; the porous metal filter tube is charged by an external high voltage power supply.

During the dust removal process, when the conductive dust reaches the surface of the porous metal filter tube, it will be loaded with the same kind of charge, causing the conductive dust to repel each other, forming a loose powder cake with small air resistance, so that the subsequent dust removal process is not easy to produce excessive pressure drop. , and the powder cake is easy to regenerate. The porous metal filter tube of the present invention has the advantages of high temperature resistance, good strength and weldability, and is very suitable for removing and collecting conductive dust in a non-corrosive atmosphere, and its conductivity is incomparable to that of a ceramic tube coated with a conductive coating. By coating the insulating paint, the technical problem of insulation between the porous metal filter pipe and the flower plate is skillfully solved. Compared with the insulating pad in the prior art, the advantages of the present invention include at least: insulating paint It is more docile with the flange and the porous metal filter tube, and the insulation effect is better and more stable. At the same time, on the part where the insulating paint is painted, the paint seals the filter channels of the porous metal filter tube, completely sealing off the gas flow, which can prevent The deposition of conductive dust, in addition, the insulating coating provides an effective and necessary electrostatic isolation interval between the porous metal filter tube and the equipment flower plate, and the insulation effect is reliable.

Preferably, the upper part of the flange is covered with a ceramic gland, and the ceramic gland compresses the flange through bolts fixed on the flower plate.

Preferably, the external high-voltage power supply charges the porous metal filter tube by means of wires welded on the flange.

Preferably, the wires are placed in the clean air chamber of the dust collector. By creatively adopting the method of connecting the high-voltage power supply on the clean gas side of the clean gas chamber, compared with the method of connecting to the dust-containing side, it can effectively prevent the electrical breakdown caused by the deposition of conductive dust on the surface of the through-wall porcelain, greatly greatly Improve security.

Preferably, the external high-voltage power supply is a pulse power supply.

Preferably, the filter pores of the porous metal filter tube are 2-200 μm, such as 2 μm, 5 μm, 10 μm, 20 μm, 30 μm, 50 μm, 80 μm, 100 μm, 120 μm, 150 μm, 180 μm or 200 μm.

Preferably, the insulating gasket includes an insulating asbestos gasket.

Preferably, the clean gas chamber is provided with a pressurized gas blowback port. After the gas containing conductive dust passes through the porous metal filter tube, the dust remains outside the porous metal filter tube to form a loose powder cake. When the powder cake thickens, the powder cake is knocked off by the back blowing of the compressed gas at the top, and the regeneration of the porous metal filter tube is realized.

Preferably, a dust bin is provided at the bottom of the dust removal chamber. The conductive dust knocked down by the blowback of the compressed gas at the top falls into the ash hopper at the lower part of the dust collector for easy recovery.

In order to further solve the insulation problem between the porous metal filter pipe and the flower plate of the dust collector, the invention introduces an insulating throat liner. Preferably, when the voltage loaded on the porous metal filter tube exceeds 5kV, a ceramic throat liner is lined between the flange and the flower plate, between the ceramic throat liner and the flower plate, and the ceramic An insulating pad is provided between the throat liner and the flange.

Preferably, the ceramic throat lining includes 50 porcelain throat lining, 95 porcelain throat lining or quartz throat lining.

Preferably, the lower edge of the ceramic throat lining is more than 5cm away from the flower plate.

Preferably, the thickness of the ceramic throat lining is greater than or equal to 4mm.

Preferably, when the voltage loaded on the porous metal filter tube exceeds 5kV and the operating temperature is not higher than 100°C, a rubber throat liner or a plastic throat liner is lined between the porous flange and the flower plate. When rubber throat liner or plastic throat liner is used, since the throat liner can act as a gas seal, the insulating gasket between the throat liner and the porous metal filter pipe and between the throat liner and the flower plate can be omitted.

Preferably, the rubber throat liner includes any of styrene-butadiene rubber throat liner, natural rubber throat liner, nitrile rubber throat liner, neoprene rubber throat liner, butadiene rubber throat liner, silicon rubber throat liner or fluororubber throat liner A sort of.

Preferably, the plastic throat liner includes any one of polytetrafluoroethylene throat liner, polyethylene throat liner, polypropylene throat liner, polyoxymethylene throat liner, phenolic resin throat liner or polystyrene throat liner.

Preferably, the lower edge of the plastic throat liner or rubber throat liner is more than 5cm away from the flower plate.

Preferably, the thickness of the plastic or rubber throat lining is greater than or equal to 4mm.

Preferably, the insulating coating has a thickness of 400-1000 μm, such as 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm or 1000 μm.

Preferably, the surface resistance of the insulating coating is not lower than 1MΩ/cm ² .

Preferably, when the gas temperature in the dedusting chamber is below 120°C, the insulating coating includes polyurethane coating, polyester coating, epoxy coating, polyester-epoxy composite powder coating, phenolic resin coating, urea-formaldehyde resin coating or polyester coating. Any of the vinyl acetal coatings.

Preferably, when the gas temperature in the dedusting chamber is higher than 120° C., the insulating coating includes epoxy paint or epoxy-modified silicone resin paint.

In order to further improve the insulating performance of the insulating coating, preferably, when the gas temperature in the dedusting chamber is higher than 120° C., insulating powder is added to the insulating coating.

Preferably, the insulating powder includes any one or a combination of at least two of alumina powder, BN powder, _BaSO powder, microsilica powder or diatomaceous earth, preferably BN powder, which not only improves the insulation of the insulating coating performance and improve the thermal conductivity of the insulating coating to avoid expansion or even cracking of the insulating coating at high temperatures.

Preferably, the insulating powder is added in an amount of 5wt% to 70wt% of the insulating coating, such as 5wt%, 6wt%, 7wt%, 8wt%, 10wt%, 12wt%, 15wt%, 18wt%, 20wt%, 22wt%, 25wt%, 28wt%, 30wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt%, 65wt% or 70wt%, etc.

Preferably, the particle size of the insulating powder is 150 mesh to 1000 mesh, such as 150 mesh, 200 mesh, 400 mesh, 600 mesh, 800 mesh or 1000 mesh.

The present invention does not limit the quantity, arrangement and length of the porous metal filter tubes, as long as the equipment can be operated under a reasonable air-to-cloth ratio. There are also no restrictions on the location of the external high-voltage power supply, the location of the high-pressure gas blowback port, and the arrangement of the wires that supply power to the porous metal filter tube. It is only necessary to ensure that each porous metal filter tube can be successfully charged for the wires that supply power to the porous metal filter tubes, and it is sufficient to ensure that the connection of the external high-voltage power supply is fully insulated from the device box.

In the second aspect, the present invention provides a method for removing conductive dust, and the method for removing conductive dust is realized by the device for removing conductive dust as described in the first aspect.

Preferably, when removing conductive dust, the charging voltage of the porous metal filter tube is 1-10kV, such as 1kV, 2kV, 3kV, 4kV, 5kV, 6kV, 7kV, 8kV, 9kV or 10kV;

Preferably, when removing conductive dust, the pulse voltage of the external high-voltage power supply is set to 1kV-10kV, such as 1kV, 2kV, 3kV, 4kV, 5kV, 6kV, 7kV, 8kV, 9kV or 10kV, etc.; the pulse width is 75-120μS, such as 70μS, 80μS, 90μS, 100μS, 110μS or 120μS etc.

In a third aspect, the present invention provides the use of the device for removing conductive dust as described in the first aspect, the device for removing conductive dust is used for purifying dust-containing gas and recovering conductive dust. The invention can be used for separating conductive dust in a gas with high temperature and no corrosive components, which is just a common gas working condition for preparing conductive dust.

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

1. The device for removing conductive dust of the present invention has the advantages of high temperature resistance, good strength, and weldability of porous metal filter tubes, and is easy to clean, and the air resistance rises slowly with the thickness of the powder cake, so it has low air resistance , High-throughput high-efficiency dust removal device suitable for conductive dust;

2. Coating insulating paint on the outside of the upper part of the porous metal filter tube, which solves the insulation between the porous metal filter tube and the dust removal slide, and improves the efficiency and safety of dust removal;

3. The present invention creatively adopts the method of connecting a high-voltage power supply on the clean gas side, which prevents electrical breakdown and increases safety compared to connecting to the dust-containing side.

Description of drawings

Fig. 1 is the structural representation of dust removal device in the embodiment 1 of the present invention;

Fig. 2 is the A-A plane sectional view of dust removal device in the embodiment 1 of the present invention;

Figure 3 is an enlarged view of a part of the dust removal device in Example 1 of the present invention;

Fig. 4 is a schematic diagram of the installation method of each component on the flower plate in Embodiment 1 of the present invention

The marks in the figure are as follows: 1: Clean air box upper cover; 2: Clean air chamber; 3: Flower plate; 4: Flange; 5: Porous metal filter tube body; 51: Porous metal filter tube top insulating paint; 61: ceramic gland; 62: ceramic throat lining; 63: insulating asbestos gasket; 7: compression bolt; 9: pipe wall; 10: powder cake; 11: wire; 12: dusty air inlet; 13: pressurized gas Blowback port; 14: Ash collection bin; 15: Dust removal room; 16: External high voltage power supply

Detailed ways

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and through specific implementation methods. However, the following embodiments are only simple examples of the present invention, and do not represent or limit the protection scope of the present invention, and the protection scope of the present invention shall be determined by the claims.

Example 1

A device for removing conductive dust, as shown in Figure 1, includes a clean air chamber 2 and a dust removal chamber 15 isolated from each other by a flower plate 3;

The top of the clean gas chamber 2 is provided with an upper cover plate 1 of the clean gas box, and a pressurized gas blowback port 13 is provided on the side;

The side of dedusting chamber 15 is provided with dust-containing airflow inlet 12, and the bottom is provided with ash collection bin 14, and indoor is provided with porous metal filter pipe 5; As shown in Figure 3, Figure 4, the bottom end sealing of porous metal filter pipe 5, porous Between the top of the metal filter tube 5 and the flower plate 3, gas sealing and electrical insulation are realized through the flange 4 and the insulating asbestos gasket 63 under the flange 4; the ceramic gland 61 on the top of the flange 4 is fixed on the The compression bolt 7 on the flower plate 3 is used to compress the flange 4; the outer side of the flange 4 and the outer side of the porous metal filter tube 5 of 20 cm below it are all coated with an insulating coating 51; as shown in Figure 2, the external high-voltage power supply 16 charges the porous metal filter tube 5 by means of the wire 11 welded on the flange 4 , and the wire 11 is placed in the clean gas chamber 2 .

As shown in Figure 3, when the voltage loaded on the metal filter tube 5 exceeds 5kV, a ceramic throat lining 62 with a thickness of 4mm is lined between the flange 4 and the flower plate 3, between the ceramic throat lining 62 and the flower plate 3, and , Between the ceramic throat lining 62 and the flange 4, an insulating asbestos gasket 63 is provided; the lower edge of the ceramic throat lining 62 is 5 cm from the flower plate 3. When the voltage loaded on the porous metal filter tube 5 exceeds 5kV and the operating temperature is not higher than 100°C, the ceramic throat liner is replaced with a rubber throat liner or a plastic throat liner.

During the dust removal process, as shown in Figure 3, the dust-laden airflow in the dust removal chamber 15 passes through the pipe wall 9 from the outside of the porous metal filter tube 5 to achieve filtration. After the clean air enters the pipe, it flows into the clean air chamber 2. The outer side of the wall 9 forms the conveyed powder cake 10 .

Example 2

The difference between the device and Example 1 is only that: the porous metal filter tube is 9, the length is 1m, the diameter is 50mm, the copper porous metal filter tube with a wall thickness of 10mm, its average pore size is 2 μm, the outside of the flange and The outside of the porous metal filter tube 10cm below it is coated with an insulating coating. The coating composition is epoxy-modified silicone resin coating doped with 70wt% 150 mesh SiC particles, the epoxy is E21 epoxy, and the silicone resin is Corning E6108 Type silicone resin, KH-550 type silane is used to connect the two, the thickness of the coating is 1000μm, the surface resistance is 20MΩ/cm ² , the ceramic of the ceramic throat lining is 95 porcelain, the thickness of the throat lining is 4mm, and the lower edge of the throat lining is lower than the lower plane of the flower plate 5cm.

The method of using this device to remove conductive dust: set the charging voltage of the porous metal filter tube to 10kV through an external high-voltage power supply, which is very suitable for filtering and removing ultra-fine aluminum powder. For ultra-fine aluminum powder with a D50 of 4 μm, the device is The powder cake resistance under the same filtering conditions is half of that of conventional filtering devices.

Example 3

The difference between the device and Example 1 is that the porous metal filter tubes are 17 porous metal filter tubes with a length of 1 m, a diameter of 100 mm, and a stainless steel porous metal filter tube with a wall thickness of 5 mm. The average pore size is 200 μm. The outer sides of the porous metal filter tubes with a thickness of 400 μm and surface resistance of 10 MΩ/cm ² are coated with an insulating coating on the outer side of the porous metal filter tube of 20 cm below.

The method of using this device to remove conductive dust: the external high-voltage power supply voltage is 1kV, and the pulse width is 75μS to charge the porous metal filter tube, which is very suitable for filtering and removing ultra-fine aluminum powder.

Example 4

The difference between the device and Example 1 is only that: the porous metal filter tubes are 20 lengths of 2m, a diameter of 200mm, and a copper porous filter tube with a wall thickness of 10mm, and its average pore size is 10 μm. The three tube bundles form an equilateral triangle to arrange the tube bundles, the distance between the tube bundles is 40cm, and the outside of the flange of the porous metal filter tube and the outside of the porous metal filter tube 15cm down from the flange are coated with insulating paint, and the composition of the paint is doped 25wt% 400 The polyester coating of α-Al ₂ O ₃ particles, the thickness of the coating is 1000 μm, and the surface resistance is 15MΩ/cm ² .

The method of using this device to remove conductive dust: the external high-voltage power supply charges the porous metal filter tube with a DC voltage of 3kV, which is very suitable for the filtration and removal of copper powder.

Example 5

The difference between the device and Example 1 is that the porous metal filter tubes are 20 stainless steel porous metal filter tubes with a length of 2m, a diameter of 200mm, and a wall thickness of 10mm. The average pore size is 15 μm. The tube bundles are arranged in a square manner, the tube bundle spacing is 50cm, the outside of the flange of the porous metal filter tube and the outside of the porous metal filter tube 20cm down from the flange are coated with insulating paint, and the paint composition is doped with 25% 400 mesh silicon powder particles Phenolic resin paint, paint thickness 1000μm, surface resistance 14MΩ/cm ² , the composition of the ceramic throat lining is quartz.

The method of using this device to remove conductive dust: charge the porous metal filter through an external pulse power supply, the charging voltage is 1kV, and the pulse width is 120μS, which is very suitable for filtering ultrafine iron powder.

Example 6

The difference between the device and Example 1 is only that: the porous metal filter tubes are 20 copper porous filter tubes with a length of 3m, a diameter of 400mm, and a wall thickness of 30mm. The average pore size is 10 μm. The principle of forming an equilateral triangle is to arrange the tube bundles, the distance between the tube bundles is 52cm, and the outside of the flange of the porous metal filter tube and the outside of the porous metal filter tube 20cm down from the flange are coated with insulating paint. Polyurethane coating of stone particles, coating thickness 1000μm, surface resistance 11MΩ/cm ² .

The method of using this device to remove conductive dust: charge the porous metal filter through an external high-voltage power supply, and the load voltage is a DC voltage of 2kV, which is very suitable for filtering and removing graphite powder.

Example 7

The difference between the device and Example 1 is only that: the porous metal filter tubes are 20 copper porous filter tubes with a length of 3m, a diameter of 400mm, and a wall thickness of 30mm. The average pore size is 10 μm. The principle of forming an equilateral triangle is to arrange the tube bundles, the distance between the tube bundles is 52cm, and the outside of the flange of the porous metal filter tube and the outside of the porous metal filter tube 20cm down from the flange are coated with insulating paint. Polyurethane coating of stone particles, coating thickness 1000μm, surface resistance 11MΩ/cm ² , install a polytetrafluoroethylene throat liner between the porous metal filter tube and the dust collector flower plate, the thickness of the throat liner is 5mm, and the lower edge of the throat liner is lower than The lower plane of the flower board is 10cm.

The method of using this device to remove conductive dust: charge the porous metal filter through an external high-voltage power supply, and the load voltage is a DC voltage of 2kV, which is very suitable for filtering and removing graphite powder.

Example 8

The difference between the device and Example 1 is that the porous metal filter tubes are 20 stainless steel porous filter tubes with a length of 3m, a diameter of 400mm, and a wall thickness of 30mm. The tube bundles are arranged in an equilateral triangle, the tube bundle spacing is 52cm, the outside of the flange of the porous metal filter tube and the outside of the porous metal filter tube 20cm down from the flange are coated with insulating paint, and the paint composition is doped with 20wt% 400 mesh barite Particle epoxy paint, paint thickness 1000μm, surface resistance 18MΩ/cm ² , install a silicone rubber throat liner between the porous metal filter tube and the flower plate of the dust collector, the thickness of the throat liner is 8mm, and the lower edge of the throat liner is lower than the flower plate The lower plane is 8cm.

The method of using this device to remove conductive dust: charge the porous metal filter through an external high-voltage power supply, and the load voltage is a DC voltage of 10kV, which is very suitable for the filtration and removal of nickel powder.

Comparative example 1

The only difference from Example 1 is that insulating gaskets are used instead of insulating coatings, specifically, common elastic asbestos mats are used instead of insulating coatings. Since the insulating properties of elastic asbestos mats are limited, and the thickness decreases greatly when compressed, resulting in The device can only work under the condition of less than 1000V, otherwise there will be an electrical breakdown accident between the charged porous metal filter tube and the flower plate, even if it works at a voltage lower than 1000V, electrical breakdown will occasionally occur, which will cause conductive dust Insufficient charge, the electrostatic repulsion therebetween is small, and the looseness of the powder cake has no obvious change. For the ultrafine aluminum powder with a D50 of 4 μm, compared with Example 2 in Comparative Example 1, the resistance of the powder cake doubles.

Comparative example 2

The only difference from Comparative Example 1 is that the porous metal filter tube is replaced by a SiC porous ceramic tube, the surface of which is coated with a conductive porous ceramic coating, and the conductive component of the coating is copper powder. At this time, it is impossible to connect wires on one side of the clean gas chamber. Instead, an electrode guide frame is placed on the lower part of the conductive porous ceramic filter tube, and the electrode guide frame is connected to an external high-voltage power supply. The structure is as shown in the accompanying drawing of CN105149092A.

Under the same voltage, for the ultrafine aluminum powder with D50 of 4 μm, compared with Example 2 in Comparative Example 2, when the dust removal process lasted only 5 minutes, a breakdown accident of an external high-voltage power supply occurred. The high-voltage power supply is introduced into the wall-through ceramic parts of the dust collector to deposit, resulting in conduction between the high-voltage power supply lead-in line and the equipment shell, resulting in a short-circuit breakdown accident.

The applicant declares that the present invention illustrates the detailed process equipment and process flow of the present invention through the above-mentioned examples, but the present invention is not limited to the above-mentioned detailed process equipment and process flow, that is, it does not mean that the present invention must rely on the above-mentioned detailed process equipment and process flow process can be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent replacement of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc., all fall within the scope of protection and disclosure of the present invention.

Claims (10)

1. A device for removing conductive dust, comprising: a clean air chamber and a dust removal chamber isolated from each other by flower plates; The dust removal chamber is provided with a porous metal filter tube; the bottom end of the porous metal filter tube is sealed, and the top end and the flower plate realize gas sealing and electrical insulation through the flange and the insulating pad under the flange; The outer side of the flange and the outer side of the porous metal filter tube 10-20 cm below the flange are coated with an insulating coating; the porous metal filter tube is charged by an external high-voltage power supply. 2. The device for removing conductive dust as claimed in claim 1, characterized in that, the upper part of the flange is covered with a ceramic gland, and the ceramic gland is compressed by bolts fixed on the flower plate the flange. 3. The device for removing conductive dust as claimed in claim 1 or 2, wherein the external high-voltage power supply charges the porous metal filter tube by means of wires welded on the flange; Preferably, the wires are placed in the clean air chamber; Preferably, the external high-voltage power supply is a pulse power supply. 4. The device for removing conductive dust according to any one of claims 1 to 3, characterized in that the filter pores of the porous metal filter tube are 2 to 200 μm; Preferably, the insulating gasket includes an insulating asbestos gasket. 5. The device for removing conductive dust according to any one of claims 1 to 4, wherein the clean gas chamber is provided with a pressurized gas blowback port; Preferably, a dust bin is provided at the bottom of the dust removal chamber. 6. The device for removing conductive dust according to any one of claims 1 to 5, characterized in that, when the voltage loaded on the porous metal filter tube exceeds 5kV, the gasket between the flange and the flower plate A ceramic throat lining, insulating pads are provided between the ceramic throat lining and the flower plate, and between the ceramic throat lining and the flange; Preferably, the ceramic throat lining includes 50 porcelain throat lining, 95 porcelain throat lining or quartz throat lining; Preferably, the lower edge of the ceramic throat lining is more than 5cm away from the flower plate; Preferably, the thickness of the ceramic throat lining is greater than or equal to 4mm. 7. The device for removing conductive dust according to any one of claims 1 to 5, characterized in that, when the voltage loaded on the porous metal filter tube exceeds 5kV and the operating temperature is not higher than 100°C, the porous metal filter tube A rubber throat liner or a plastic throat liner is lined between the flange and the flower plate; Preferably, the rubber throat liner includes any of styrene-butadiene rubber throat liner, natural rubber throat liner, nitrile rubber throat liner, neoprene rubber throat liner, butadiene rubber throat liner, silicon rubber throat liner or fluororubber throat liner A sort of; Preferably, the plastic throat liner includes any one of polytetrafluoroethylene throat liner, polyethylene throat liner, polypropylene throat liner, polyoxymethylene throat liner, phenolic resin throat liner or polystyrene throat liner; Preferably, the lower edge of the plastic throat liner or rubber throat liner is more than 5cm away from the flower plate; Preferably, the thickness of the plastic or rubber throat lining is greater than or equal to 4mm. 8. The device for removing conductive dust according to any one of claims 1-5, characterized in that the thickness of the insulating coating is 400-1000 μm; Preferably, the surface resistance of the insulating coating is not lower than 1MΩ/cm ² ; Preferably, when the gas temperature in the dedusting chamber is below 120°C, the insulating coating includes polyurethane coating, polyester coating, epoxy coating, polyester-epoxy composite powder coating, phenolic resin coating, urea-formaldehyde resin coating or polyester coating. Any of the vinyl acetal coatings; Preferably, when the gas temperature in the dedusting chamber is higher than 120°C, the insulating coating includes epoxy paint or epoxy-modified silicone resin paint; Preferably, when the gas temperature in the dedusting chamber is higher than 120°C, insulating powder is added to the insulating coating; Preferably, the insulating powder includes any one or a combination of at least two of alumina powder, BN powder, _BaSO powder, microsilica powder or diatomaceous earth, preferably BN powder; Preferably, the insulating powder is added in an amount of 5wt% to 70wt% of the insulating coating; Preferably, the particle size of the insulating powder is 150 mesh to 1000 mesh. 9. A method for removing conductive dust, characterized in that, the method for removing conductive dust is realized by the device for removing conductive dust according to any one of claims 1 to 8; Preferably, when removing conductive dust, the charging voltage of the porous metal filter tube is 1-10kV; Preferably, when removing conductive dust, the pulse voltage of the external high-voltage power supply is set to 1 kV-10 kV, and the pulse width is 75-120 μS. 10. The use of the device for removing conductive dust according to any one of claims 1 to 8, characterized in that the device for removing conductive dust is used for purifying dust-containing gas and recovering conductive dust.