JP6994420B2 - Discharge electrode and dust collector - Google Patents

Description

The present invention relates to a discharge electrode that generates plasma discharge by applying a high voltage and a dust collector including the discharge electrode.

Conventionally, a dust collector has been used to decompose and remove odorous substances such as volatile organic compounds (hereinafter referred to as "VOC") contained in air discharged from a printing machine or painting equipment of a factory.

For example, in Patent Document 1, a wire is used for a high voltage application electrode, a dielectric material coated with an adsorbent carrying a metal catalyst is arranged inside the barrier material, and a cylindrical ground electrode is placed outside the barrier material. Disclosed is a gas processing apparatus that decomposes VOC by applying a high voltage to a high voltage application electrode and a ground electrode to perform plasma discharge.

Japanese Unexamined Patent Publication No. 2005-193151

However, since the plasma gas processing apparatus described in Patent Document 1 uses a wire having a small wire diameter for the internal electrode, the gap generated inside the barrier material becomes wide, and when plasma discharge is performed in this state. , There is a problem that plasma discharge is not stable.

The present invention has been made to solve the above-mentioned problems, and to provide a discharge electrode and a dust collector capable of stably continuing the decomposition of odorous substances such as VOC and stably performing plasma discharge. The purpose.

In order to achieve the above object, the first discharge electrode of the present invention is provided concentrically with a cylindrical insulating tube, an external electrode provided on the outer peripheral portion of the insulating tube, and the inside of the insulating tube. A cylindrical internal electrode having a different diameter with an enlarged outer diameter of the discharge portion is provided, and a catalytic material is provided in the gap between the portion of the insulating tube facing the discharge portion of the internal electrode and the discharge portion of the internal electrode. Is filled, and the gap is configured to allow air containing an odorous substance to flow.

According to the first discharge electrode of the present invention, the gap between the discharge electrodes can be narrowed and the pressure loss in the gap between the discharge electrodes is reduced, so that air containing an odorous substance can easily flow through the gap. Plasma discharge can be generated stably.

The second discharge electrode of the present invention includes, in the above-mentioned first discharge electrode, a catalyst fixing member fixed to both ends of the discharge portion in the axial direction inside the insulating tube, and the catalyst fixing member is a catalyst fixing member. It is preferable that the catalyst substance is sandwiched from both ends in the axial direction and held in the gap.

According to the second discharge electrode of the present invention, the displacement of the catalytic substance in the gap can be reliably prevented.

The third discharge electrode of the present invention is the first or second discharge electrode described above, and the external electrode is composed of a plate-shaped elastic body wound around the outer peripheral portion of the insulating tube, and is in the circumferential direction when wound. It is preferable to have an overlap portion in which both ends overlap.

According to the third discharge electrode of the present invention, the external electrode can be reliably adhered to the insulating tube and can surely cover the periphery of the discharge portion of the internal electrode, so that abnormal discharge during plasma discharge can be prevented. can.

The first dust collector of the present invention is a dust collector provided with any of the above-mentioned first to third discharge electrodes, and by rotating, it has an action of adsorbing an odorous substance on an adsorbent contained therein and heated air. An adsorption rotor that continuously repeats the desorption action of the odorous substance from the adsorbent, a heater that heats the air containing the desorbed odorous substance by passing through the adsorption rotor, and a plurality of the discharge electrodes. It is characterized by having a high voltage power source for applying a high voltage to the discharge electrode, and a plasma discharge unit for decomposing an odorous substance in the heated air heated by the heater.

According to the first dust collector of the present invention, by heating the air containing an odorous substance with a heater, the temperature gradient generated in the discharge portion of the discharge electrode during plasma discharge can be suppressed, and by-products such as tar can be suppressed. It is possible to stably continue the decomposition of odorous substances without generating plasma.

The second dust collector of the present invention is the above-mentioned first dust collector, and it is preferable that a catalyst unit having a catalytic substance is provided on the exhaust side of the plasma discharge unit.

According to the second dust collector of the present invention, by providing the catalyst portion on the exhaust side of the plasma discharge portion, the undecomposed odorous substance can be decomposed without leaking in the plasma discharge portion.

The third dust collector of the present invention is the above-mentioned first or second dust collector, in which a plurality of ventilation holes through which air containing a desorbed odorous substance flows are uniformly formed in the lateral direction, and the insulating pipe is formed. A horizontally long board that supports the discharge electrode so as to communicate with the ventilation holes, a plurality of rectifying plates provided on the air introduction side of the board and having a large number of holes opened, and one that introduces air into the inside. A case body having an introduction port and a plasma unit having the introduction port are provided, and the air introduced into the case body through the introduction port is uniformly rectified to the ventilation hole through the hole of the rectifying plate. Is preferable.

According to the third dust collector of the present invention, air containing an odorous substance can be evenly introduced into a plurality of discharge electrodes arranged horizontally and widely, so that the discharge electrodes stably generate plasma discharge. And the decomposition of odorous substances can be continued stably.

The fourth dust collector of the present invention is the above-mentioned third dust collector, and the straightening vane is a first straightening vane provided on the air introduction side and a second straightening vane provided on the exhaust side from the first straightening vane. The first straightening vane is provided with a plate, and the first straightening vane is provided at a position facing the introduction port, and has an inclined plate that is bent toward the holes at both ends in the longitudinal direction of the second straightening vane. It is preferable that a plurality of pores are formed in the plate, and the holes of the second straightening vane are formed so as to have a larger diameter toward both ends in the longitudinal direction.

According to the fourth dust collector of the present invention, the air containing the odorous substance can be diffused and evenly rectified, so that the discharge electrode can stably generate plasma discharge and the decomposition of the odorous substance is stable. Can be continued.

The fifth dust collector of the present invention is any of the first to fourth dust collectors described above, and includes an electrode support member that electrically contacts the internal electrode and supports a plurality of the discharge electrodes. It is preferable that the high-pressure power source applies a high voltage to the internal electrode via the electrode support member, and the electrode support member is attached to the exhaust side of the air containing the desorbed odorous substance flowing through the discharge electrode. ..

According to the fifth dust collector of the present invention, it is possible to prevent an abnormal discharge in which the internal electrode and the external electrode are short-circuited via an odorous substance.

According to the present invention, various excellent effects can be obtained, such as stable decomposition of odorous substances and stable plasma discharge.

It is a block diagram which shows typically the whole structure of the dust collector which concerns on one Embodiment of this invention. It is a schematic diagram which shows the whole structure of the dust collector which concerns on one Embodiment of this invention. In the dust collector according to the embodiment of the present invention, (1) is a cross-sectional view showing a discharge electrode, (2) is a plan view showing a catalyst fixing member, and (3) is a plan view showing an external electrode. In the dust collector according to the embodiment of the present invention, (1) a side view showing a plasma discharge unit, and (2) a plan view showing an intermediate electrode support member. Is a dust collector according to an embodiment of the present invention, (1) is a plan view showing a plasma unit, and (2) is a side view showing a plasma unit. In the dust collector according to the embodiment of the present invention, (1) is a plan view showing a second straightening vane, (2) is a side view showing a case body, and (3) is a side view and a plan view showing the first straightening body. It is a figure. It is a side view which shows the structure from the preheating heater to the heat exchanger in the dust collector of one Embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
The dust collector 1 according to the present embodiment will be described with reference to the drawings. First, the overall configuration of the dust collector 1 will be described with reference to FIGS. 1 and 2. FIG. 1 is a block diagram schematically showing the overall configuration of the dust collector 1, and FIG. 2 is a schematic diagram showing the overall configuration of the dust collector 1. In the following description, for convenience, the front side in the vertical direction of the paper surface in FIG. 2 is referred to as the front side (front side), and the left-right and up-down directions are based on FIG.

[Overall configuration of dust collector]
The dust collector 1 according to the present embodiment rotates with a primary fan 2 that sucks air containing VOC of an odorous substance and a primary filter 3 that collects dust in the air sucked by the primary fan 2. A suction rotor 4 that continuously repeats suction and desorption of VOC, a secondary blower 5 that sucks air for desorbing VOC adsorbed on the suction rotor 4, and dust in the air sucked by the secondary blower 5. A secondary filter 6 for collecting the air, a preheating heater 7 for heating the air containing the VOC desorbed from the adsorption rotor 4, a plasma discharge unit 8 for decomposing the VOC desorbed from the adsorption rotor 4, and a plasma discharge unit. The catalyst unit 9 provided on the exhaust side of No. 8, the heat exchanger 10 for exchanging heat between the air containing heat after VOC decomposition and the air for desorbing the VOC, and the VOC are desorbed. It is configured to include a rotor heating heater 11 for heating air for heating.

The dust collector 1 is provided with a housing 12. The inside of the housing 12 is divided into a lower region 15, an intermediate region 16 and an upper region 17 in order from the bottom by horizontally formed partition plates 13 and 14.

The primary fan 2 includes a blade portion 19 rotatably provided in the fan chamber 18 formed in the upper region 17, and a motor 20 mounted on the upper surface of the fan chamber 18. An exhaust chamber 21 is formed on the right side of the fan chamber 18.

The primary filter 3 is arranged in the suction chamber 22 formed on the right side of the lower region 15. A suction port 23 is formed at the lower part of the right side surface of the housing 12 so as to face the primary filter 3.

The adsorption rotor 4 is arranged in the intermediate region 16 and contains an adsorbent (not shown) made of synthetic zeolite. The suction rotor 4 is configured to be horizontally rotated by a motor 24 arranged in the lower region 15. In FIG. 2, the region on the right side of the adsorption rotor 4 is the first passage region 4A of the air containing the VOC filtered by the primary filter 3 from the suction port 23, and the region on the left side thereof is the heating heated by the rotor heater 11. It is the second passage area 4B of air. Then, as the adsorption rotor 4 rotates, the adsorbent passes through these two passage areas 4A and 4B alternately and repeatedly.

The secondary blower 5 includes a blade portion 26 rotatably provided in a fan case 25 formed in the lower left side of the lower region 15, and a motor 27 attached to the left side of the fan case 25. The second exhaust side of the second passage region 4B of the suction rotor 4 and the suction side of the fan case 25 are connected via a duct 28. Since the secondary blower 5 sucks air containing heat after being desorbed from the adsorbent of the adsorption rotor 4, it is desirable that the secondary blower 5 has a heat-resistant structure.

The secondary filter 6 is arranged, for example, on the upper left side on the outside of the housing 12, and is connected to the first suction side of the second passage region 4B of the suction rotor 4 via a duct 29.

The preheating heater 7 is arranged in the intermediate region 16, and the exhaust side of the fan case 25 of the secondary blower 5 and the suction side of the preheating heater 7 are connected to each other via a duct 31.

The plasma discharge unit 8 is arranged in the intermediate region 16, and the exhaust side of the preheating heater 7 and the suction side of the plasma discharge unit 8 are connected to each other. The plasma discharge unit 8 is composed of a high voltage power supply 62 and a plasma unit 30. The details of the plasma discharge unit 8 will be described later.

The catalyst unit 9 is arranged in the intermediate region 16, and the exhaust side of the plasma discharge unit 8 and the suction side of the catalyst unit 9 are connected to each other. The catalyst unit 9 is provided with a large number of catalysts 32 (see FIG. 7) as catalyst substances. The catalyst 32 has a function of oxidatively decomposing VOCs at a constant temperature (for example, several 100 ° C.) or higher. The catalyst unit 9 houses a large number of catalysts 32 and is arranged on the exhaust side of the plasma discharge unit 8, so that the VOC that could not be completely decomposed by the plasma discharge unit 8 can be reliably decomposed by the catalyst unit 9. .. Therefore, even if there is a situation in which the plasma discharge in the plasma discharge unit 8 is desired to be temporarily stopped due to a reason that the temperature inside the plasma discharge unit 8 becomes so high that the plasma discharge cannot be stably maintained, the VOC is performed. It is practical because the plasma discharge in the plasma discharge unit 8 can be temporarily stopped without re-releasing the contained air into the atmosphere.

The heat exchanger 10 includes a heat radiating side 10A through which air containing heat after VOC decomposition passes and a heat receiving side 10B through which air for desorbing VOC passes, and has a predetermined heat exchange efficiency. is doing. The heat exchanger 10 is arranged in the intermediate region 16, and the exhaust side of the catalyst unit 9 and the intake side of the heat dissipation side 10A of the heat exchanger 10 are connected to each other. Further, the suction side of the heat receiving side 10B of the heat exchanger 10 is connected to the first exhaust side of the second passing region 4B of the adsorption rotor 4 via the duct 33.

The rotor heater 11 is arranged in the intermediate region 16, is connected to the exhaust side of the heat receiving side 10B of the heat exchanger 10 via the duct 34, and is connected to the second suction side of the second passing region 4B of the adsorption rotor 4. It is connected via a duct 35. By heating the air after heat exchange in the heat exchanger 10, the electric power applied to the rotor heater 11 can be saved.

[Plasma discharge part]
Next, the plasma discharge unit 8 will be described in detail with reference to FIGS. 3 to 7. In FIG. 3, (1) is a cross-sectional view showing a discharge electrode, (2) is a plan view showing a catalyst fixing member, (3) is a plan view showing an external electrode, and (1) is a side surface showing a plasma discharge portion in FIG. FIG. 2, (2) is a plan view showing an intermediate electrode support member, (1) is a plan view showing a plasma unit in FIG. 5, (2) is a side view showing a plasma unit, and (1) in FIG. 6 is a second rectification. A plan view showing the plate, (2) is a side view showing the case body, (3) is a side view and a plan view showing the first rectifying plate, and FIG. 7 is a side view showing the configuration from the preheating heater to the heat exchanger. Is.

(Discharge electrode)
The plasma discharge unit 8 is provided with a plurality of discharge electrodes 40. As is well shown in FIG. 3 (1), the discharge electrode 40 includes a cylindrical insulating tube 41, an internal electrode 42 concentrically provided inside the insulating tube 41, an insulating tube 41, and an internal electrode 42. The catalyst material 44 filled in the gap 43 between the two, the catalyst fixing member 45 provided so as to sandwich and fix the catalyst material 44 from the upper and lower ends in the axial direction inside the insulating pipe 41, and the insulating pipe 41. It is configured to include an external electrode 46 provided on the outer peripheral portion.

A quartz tube (hydrogen acid molten product) is used as an insulating material for the insulating tube 41, and the internal electrode 42 is made of stainless steel. The internal electrode 42 has a discharge portion 47 having a large diameter (for example, a few mm) columnar shape with an enlarged outer diameter, and a small diameter (for example, several mm) electrode extending upward from the upper end portion of the discharge portion 47. It is formed into a cylindrical shape having a different diameter by the shaft 48.

A screw hole is formed at the center of each of the upper and lower ends of the discharge portion 47. Further, the corners of the upper and lower ends of the discharge portion 47 are curved so that the discharge does not concentrate on the edges. The lower end portion 51 of the electrode shaft 48 is screwed and screwed into the screw hole at the upper end portion of the discharge portion 47, whereby the electrode shaft 48 is fixed to the discharge portion 47. Further, the upper end portion 52 of the electrode shaft 48 projects upward from the upper end surface of the insulating tube 41, and a female screw is processed.

The catalyst substance 44 is a granular catalyst, and is filled only in the cylindrical gap 43 formed between the discharge portion 47 of the internal electrode 42 and the portion of the insulating tube 41 facing the discharge portion 47.

The catalyst fixing member 45 is made of ceramic and has a substantially disk shape, and is provided above and below the discharge portion 47. As is well shown in FIG. 3 (2), the inner ring portion 53 and the outer ring portion 54, which are doubly formed around the circular center hole 50, and the respective ring portions 53, 54 are provided. It is configured to include a cross-shaped connecting portion 55 to be connected. The center hole 50 of the catalyst fixing member 45 is formed at a position corresponding to the screw hole at the lower end of the discharge portion 47. The outer diameter of the inner ring portion 53 is formed shorter than the outer diameter of the discharge portion 47, and four fan-shaped ventilation holes 56 are formed in the circumferential direction between the inner ring portion 53 and the outer ring portion 54. ing. Further, the radial length of the connecting portion 55 is equal to the inner diameter of the insulating pipe 41 (the radial length of the connecting portion 55 is shortened by several mm from the inner diameter of the insulating pipe 41 to secure a gap so that it can be easily inserted. The outer diameter of the outer ring portion 54 may be shorter than the inner diameter of the insulating tube 41. As a result, fan-shaped notches 57 are formed at four points in the circumferential direction on the outside of the outer annulus portion 54. The radial lengths of the ventilation holes 56 and the notch 57 are formed to be smaller than the outer diameter of the catalytic material.

The upper catalyst fixing member 45 is fixed to the upper end portion of the discharge portion 47 by screwing the lower end portion 51 of the electrode shaft 48 into the screw hole at the upper end portion of the discharge portion 47 from above via the center hole 50. The catalyst fixing member 45 on the side is fixed to the lower end portion of the discharge portion 47 by screwing a bolt 58 into the screw hole at the lower end portion of the discharge portion 47 from below via the center hole 50. As a result, the catalyst substance 44 is held in a state of being filled only in the gap 43 between the discharge portion 47 and the portion of the insulating tube 41 facing the discharge portion 47, and can be prevented from shifting. Further, the upper internal space 59 and the lower internal space 60 of the insulating pipe 41 communicate with the gap 43 through the ventilation hole 56 and the notch 57. In order to ensure the retention of the catalyst substance 44, the catalyst substance 44 may be filled beyond the gap 43.

As shown well in FIG. 3 (3), the external electrode 46 is formed by winding a plate-shaped elastic body made of a stainless steel leaf spring around the outer peripheral portion of the insulating tube 41. The external electrode 46 is formed with an overlapping portion 61 in which both ends in the circumferential direction overlap each other, and it is preferable to leave a straight portion 49 at the tip of the overlapping portion 61. By strongly winding the external electrode 46 around the outer peripheral portion of the insulating tube 41 by its elastic force and fixing it, a gap is generated between the outer peripheral portion of the insulating tube 41 and the external electrode 46, and an abnormal discharge occurs. Can be prevented.

In the present embodiment, the inner diameter of the insulating tube 41 is narrowed to about 10 mm, and the radial length of the gap 43 is narrowed to several mm. In this way, by making the discharge portion 47 of the internal electrode 42 having a large diameter, the ratio of the discharge portion 47 to the inside of the insulating tube 41 is increased, and the inner diameter of the insulating tube 41 is not reduced. The gap 43 between the insulating tube 41 and the portion facing the discharge portion 47 can be narrowed. As a result, the catalyst substance 44 filled in the gap 43 can be reduced, so that the pressure loss during air flow can be reduced.

Further, the electrode shaft 48, which is not involved in the discharge of the internal electrode 42, has a small diameter of several mm, and the catalyst fixing member 45 further uses the catalyst fixing member 45 to transfer the catalyst substance 44 to both ends of the discharge portion 47 without obstructing the flow of air from the ventilation holes 56. Since it is configured to be held in the sandwiching gap 43 from the portion, it is not necessary to fill the catalyst substance 44 to an unnecessary portion that is not involved in the discharge, and by suppressing the catalyst substance 44 to the minimum necessary, the discharge electrode 40 The pressure loss of air can be reduced.

Further, by setting the length of the discharge unit 47 in the vertical direction as short as several tens of mm and suppressing the length of the discharge unit 47 to the minimum necessary, the filling amount of the catalyst substance 44 can be reduced and the plasma discharge can be performed. The temperature gradient of time can be suppressed.

Further, if the wall thickness of the insulating tube 41 is set to several mm and increased, the insulating property against heat of the insulating tube 41 becomes high, so that the plasma discharge can be stably maintained even if the discharge electrode 40 is affected by heat. be able to.

(High voltage power supply)
As is well shown in FIG. 4 (1), the plasma discharge unit 8 is provided with a high voltage power supply 62 for applying a high voltage to the discharge electrode 40. In the present embodiment, the high voltage power supply 62 used has an AC voltage of 10 KV, but is not limited thereto. The high-voltage power supply 62 is connected to the internal electrode feeding unit 63 and the external electrode feeding unit 64, which are arranged in parallel, via cables 65 and 66, respectively. The power feeding section 63 for the internal electrode and the feeding section 64 for the external electrode are each formed in a vertically long linear shape having a structure in which a straight pipe made of ceramics is placed on an elongated screw portion. The power feeding unit 63 for the internal electrode and the power feeding unit 64 for the external electrode are formed through a horizontally elongated rectangular plate-shaped ceramic board 67 and are provided so as to extend downward and vertically from the board 67. The cables 65 and 66 are connected to the lower end portions of the internal electrode feeding unit 63 and the external electrode feeding unit 64.

The upper end portion of the internal electrode feeding portion 63 is fixed to the upper end portion 52 of the electrode shaft 48 of the internal electrode 42 via the upper electrode supporting member 68, and the upper end portion of the external electrode feeding portion 64 is the intermediate electrode supporting member 69. It is fixed to the external electrode 46 via. In the present embodiment, for the four discharge electrodes 40 arranged in series on the ceramic board 67, the high-voltage power supplies 62 to the feeding portions 63 and 64, the upper electrode support member 68, and the intermediate electrode support member are provided. A high voltage is configured to be applied via 69. The number of discharge electrodes 40 arranged together in series is appropriately selected so as to generate an optimum plasma discharge according to the length of the discharge portion 47 of the discharge electrode 40 and the output (W) of the high voltage power supply 62. It is good to discharge.

As shown in FIG. 4 (1), the four discharge electrodes 40 are arranged on the board 67 via a packing 84 made of a blanket-like heat insulating material, and cylinders are provided on both sides of the discharge electrodes 4, respectively. A column 70 having a shape is erected. A support member 71 is hung in a horizontal posture between the upper ends of the columns 70 on both sides, and both ends of the support member 71 are screwed to the tops of the columns 70, respectively. As a result, the support member 71 abuts on the upper surface of the insulating tube 41 of each discharge electrode 40, and each discharge electrode 40 is stably supported on the board 67.

The upper electrode support member 68 forms an obtuse angle downward from the internal electrode mounting piece 72, which is arranged parallel to the board 67 and fixed to the upper end portion 52 of the electrode shaft 48 of the internal electrode 42. It is formed in a dogleg shape with an inclined piece 73 that is bent and extends toward the board 67. Further, the lower end of the inclined piece 73 is bent to the opposite side along the upper surface of the board 67 to form a folded portion 74. The folded-back portion 74 is subjected to female screw processing, and the upper electrode support member 68 is provided with the internal electrode feeding portion 63 by the male screw 75 screwed from above the folded-back portion 74 into the upper end portion of the internal electrode feeding portion 63. It is fixed to the board 67 together with.

Mounting holes (not shown) are formed at equal intervals at positions corresponding to the upper end 52 of the electrode shaft 48 of the internal electrode 42 in the internal electrode mounting piece 72 of the upper electrode support member 68, and the mounting holes (not shown) are formed from above via the mounting holes. The upper electrode support member 68 is fixed to the electrode shaft 48 of the internal electrode 42 by a male screw 76 screwed into the upper end portion 52 of the electrode shaft 48.

The intermediate electrode support member 69 has an external electrode mounting piece 77 arranged parallel to the board 67 between the board 67 and the internal electrode mounting piece 72 of the upper electrode support member 68, and downward from the external electrode mounting piece 77. It is formed by a vertical piece 78 that is bent at a right angle. Further, the lower end of the vertical piece 78 is bent to the opposite side along the upper surface of the board 67 to form a folded portion 79. The folded-back portion 79 is subjected to female screw processing, and the intermediate electrode support member 69 is provided with the external electrode feeding portion 64 by the male screw 80 screwed from above the folded-back portion 79 into the upper end portion of the external electrode feeding portion 64. It is fixed to the board 67 together with.

As is well shown in FIG. 4 (2), the external electrode mounting piece 77 of the intermediate electrode support member 69 has four mounting holes 81 opened at equal intervals at positions corresponding to the respective discharge electrodes 40. A round hole 82 opened on the most vertical piece 78 side is formed. Each mounting hole 81 has a shape in which a rectangular notch 83 is formed in a part of a circle concentric with the same spacing as the mounting hole of the upper electrode support member 68. A discharge electrode 40 around which an external electrode 46 is wound is fitted in each mounting hole 81, and a straight portion 49 at the tip of an overlap portion 61 of the external electrode 46 can be accommodated in the notch 83. Further, the support columns 70 on the power feeding portions 63 and 64 sides can be fitted into the round holes 82. After the discharge electrode 40 around which the external electrode 46 is wound is fitted in the mounting hole 81 of the intermediate electrode support member 69, the external electrode 46 is concentrically rotated along the insulating tube 41 to be accommodated in the notch 83. The straight portion 49 at the tip of the external electrode 46 is elastically abutted against the intermediate electrode support member 69 via the mounting hole 81. As a result, the external electrode 46 and the intermediate electrode support member 69 are surely in contact with each other without the need for screwing, so that abnormal discharge due to insufficient contact between the external electrode 46 and the intermediate electrode support member 69 can be prevented. ..

By configuring the upper electrode support member 68 and the intermediate electrode support member 69 in this way, the upper electrode support member 68 and the intermediate electrode support member 69 are connected to the feeding portions 63 and 64 at the shortest distance without contacting each other. To. Further, a high voltage is applied from the high voltage power supply 62 via the cables 65 and 66 connected to the lower end portions of the feeding portions 63 and 64 extending downward from the board 67 in the vertical direction. As a result, the connection work of the cables 65 and 66 can be simplified, and the cables 65 and 66 do not bend and approach each other to cause a short circuit, so that a high voltage is stably applied to the discharge electrode 40. can do.

Further, if a structure is adopted in which a high voltage is applied from the introduction side of air containing VOC, since the VOC has conductivity, for example, the internal electrode and the external electrode are connected to each other via the VOC leaked from the discharge electrode due to insufficient sealing or the like. There is a risk of short circuit. However, in the present embodiment, since a structure in which a high voltage is applied to the internal electrode 42 through the upper electrode support member 68 provided on the exhaust side of the air from which the VOC has been removed is adopted, the structure is adopted via the conductive VOC. The internal electrode 42 and the external electrode 46 do not short-circuit. Further, since the flow direction of the air exhausted from the discharge electrode 40 is also set to be opposite to the side where the external electrode 46 is installed, the short circuit between the internal electrode 42 and the external electrode 46 is prevented. It is valid.

(Plasma unit)
As shown in FIGS. 5 (1) and 5 (2), the plasma unit 30 has 22 rows of uniform discharge electrodes 40 arranged in series at equal intervals on a ceramic board 67. They are juxtaposed at intervals, and a total of 88 discharge electrodes 40 are provided. The packing 84 (see FIG. 4 (1) and the like) interposed between the board 67 and the board 67 and the insulating tube 41 has a lower end opening surface of the insulating tube 41 on the side where air is introduced into the discharge electrode 40. Circular ventilation holes 85 are formed at the corresponding positions. The board 67 is made by molding inorganic refractory fibers into a plate shape using an inorganic and organic adhesive, has excellent fire resistance, and can be machined to open a vent hole 85. Further, by sandwiching the blanket-shaped heat insulating material as the packing 84 between the row of the discharge electrodes 40 and the board 67, the air containing the VOC is introduced into each discharge electrode 40 without leaking.

As shown in FIGS. 5 (2) and 6 (1) to (3), the plasma unit 30 has a case body 90 made of SUS below the board 67 (on the side where air including VOC is introduced). Is provided. The case body 90 has a horizontally long box shape in the longitudinal direction of the board 67, and a rectangular introduction port 91 is opened in the central portion of the bottom surface. Inside the case body 90, a first straightening vane 92 and a second straightening vane 93 are provided so that air containing VOCs is evenly introduced into each of the discharge electrodes 40 arranged side by side on the board 67. .. The first straightening vane 92 is arranged directly above the introduction port 91 of the case body 90, and the second straightening vane 93 is horizontally provided at an intermediate position that partitions the inside of the case body 90 up and down on the exhaust side from the first straightening vane 92. ing.

As well shown in FIGS. 6 (2) and 6 (3), the first straightening vane 92 has a rectangular shape slightly smaller than the introduction port 91 in a plan view, and is centered on the central bending line 94. A pair of left and right inclined plates 95 that are bent upward in the left-right longitudinal direction are provided. Each of the inclined plates 95 has a large number of pores 96 for ventilation. Each inclined plate 95 is suspended from the second straightening vane 93 by four vertical rods 97.

As is well shown in FIGS. 6 (1) and 6 (2), the second straightening vane 93 has an elongated strip shape in the left-right direction. In the second straightening vane 93, for example, a large number of circular straightening vanes 98 are opened at equal intervals at positions facing the ventilation holes 85 of the board 67. The inner diameter of the rectifying hole 98 is the smallest near the central portion, and is formed so as to increase toward both ends in the left-right direction.

[Action of dust collector]
Next, the operation of the dust collector 1 having the above-described configuration will be described with reference to FIGS. 1 to 7.

The air containing VOCs is sucked into the inside of the housing 12 from the suction port 23 by the primary fan 2, and after the dust in the air is collected by the primary filter 3, it passes through the lower region 15 in the housing 12. Then, it is sent to the suction rotor 4. The adsorption rotor 4 repeatedly adsorbs and desorbs VOCs in the air while continuously rotating at a constant speed. In the adsorption rotor 4, VOCs in the air are adsorbed by the adsorbent and removed, and the air from which the VOCs have been removed flows through the primary fan 2 and then is released into the atmosphere as clean air. In the present embodiment, the suction rotor 4 is set to a rotation speed of about one rotation in several tens of minutes, but this rotation speed may be changed according to the situation of VOC removal.

On the other hand, the air sucked by the secondary blower 5 flows into the adsorption rotor 4 through the duct 29 after the dust in the air is collected by the secondary filter 6. Air is sent to the heat receiving side 10B of the heat exchanger 10 while cooling the portion having heat after the VOC is desorbed inside the adsorption rotor 4.

The air sent to the heat receiving side 10B of the heat exchanger 10 exchanges heat with the air having heat after VOC decomposition sent to the heat dissipation side 10A of the heat exchanger 10. The air heated by heat exchange on the heat receiving side 10B of the heat exchanger 10 is sent to the rotor heater 11 through the duct 34 and heated to a constant temperature (for example, several 100 ° C.).

The air heated to a constant temperature in the rotor heater 11 is introduced into the adsorption rotor 4 through the duct 35, and the adsorbed VOC is desorbed. The air containing the desorbed VOC is sent to the preheating heater 7 through the duct 28, the secondary blower 5, and the duct 31.

Air containing VOCs heated to a constant temperature (for example, several 100 ° C.) in the preheating heater 7 is sent to the plasma unit 30 of the plasma discharge unit 8. In the plasma unit 30, air containing VOCs is introduced into the case body 90 via the introduction port 91, and is evenly diffused over the entire width of the case body 90 by the action of the first straightening vane 92. The air containing VOC diffused to the entire width of the case body 90 is further evenly rectified in the case body 90 by the second straightening vane 93, and then a plurality of air are arranged side by side through the ventilation holes 85 of the board 67. It is evenly introduced into the discharge electrode 40.

At each discharge electrode 40, plasma discharge is generated by applying a high voltage from the high voltage power supply 62, and VOCs in the circulating air are decomposed. Further, also in the catalyst unit 9, the VOC remaining in the air is decomposed by the oxidative decomposition action of the catalyst 32, and the air in which the VOC is decomposed in the plasma discharge unit 8 and the catalyst unit 9 is the heat exchanger 10. It is sent to the heat dissipation side 10A.

In the heat radiating side 10A of the heat exchanger 10, the air in which the VOC is decomposed exchanges heat with the air sent to the heat receiving side 10B, radiates heat and is cooled, and then is released as clean air into the atmosphere.

The description of the above embodiment shows one aspect of the electrostatic precipitator according to the present invention, and the technical scope of the present invention is not limited to the above embodiment.

The technique of the present invention can be used for a dust collector that decomposes and removes odorous substances such as VOC contained in air discharged from a printing machine or painting equipment of a factory.

1 Dust collector 4 Adsorption rotor 7 Preheating heater 8 Plasma discharge part 9 Catalyst part 10 Heat exchanger 30 Plasma unit 40 Discharge electrode 41 Insulation tube 42 Internal electrode 43 Gap 44 Catalyst material 45 Catalyst fixing member 46 External electrode 47 Discharge part 61 Overlap Part 62 High-voltage power supply 67 Board 68 Upper electrode support member 85 Vent hole 90 Case body 91 Inlet port 92 1st rectifying plate 93 2nd rectifying plate 95 Inclined plate 96 Pore 98 rectifying hole

Claims (8)

A discharge electrode that generates plasma discharge when a high voltage is applied.
Cylindrical insulation tube and
An external electrode provided on the outer peripheral portion of the insulating tube and
A cylindrical internal electrode having a different diameter, which is concentrically provided inside the insulating tube and has an enlarged outer diameter of the discharge portion, is provided.
The gap between the portion of the insulating tube facing the discharge portion of the internal electrode and the discharge portion of the internal electrode is filled with a catalytic substance, and the gap is configured to allow air containing an odorous substance to flow. A discharge electrode characterized by that. A catalyst fixing member is provided inside the insulating tube to be fixed to both ends in the axial direction of the discharge portion, and the catalyst fixing member sandwiches the catalyst substance from both ends in the axial direction and holds the catalyst substance in the gap. The discharge electrode according to claim 1, which is configured in 1. The discharge electrode according to claim 1 or 2, wherein the external electrode is formed of a plate-shaped elastic body wound around the outer peripheral portion of the insulating tube, and has an overlapping portion in which both ends in the circumferential direction overlap when wound. A dust collector provided with the discharge electrode according to any one of claims 1 to 3.
An adsorption rotor that continuously repeats the adsorption action of the odorous substance on the adsorbent contained inside and the desorption action of the odorous substance from the adsorbent by the heated air by rotating.
A heater that heats the air containing the odorous substance desorbed by passing through the adsorption rotor, and
A plasma discharge unit that has a plurality of the discharge electrodes and a high-voltage power source that applies a high voltage to the discharge electrodes and decomposes odorous substances in the heated air heated by the heater.
A dust collector characterized by being equipped with. The dust collector according to claim 4, wherein a catalyst unit having a catalytic substance is provided on the exhaust side of the plasma discharge unit. A board that supports the discharge electrode so that a plurality of ventilation holes through which air containing a desorbed odorous substance flows are uniformly formed in the longitudinal direction and the insulating pipe communicates with the ventilation holes.
A case body provided on the air introduction side of the board and formed with a plurality of straightening vanes having a large number of holes and one introduction port for introducing air inside.
Equipped with a plasma unit with
The dust collector according to claim 4 or 5, wherein the air introduced into the case body through the introduction port is evenly rectified into the ventilation holes through the holes of the rectifying plate. The straightening vane includes a first straightening vane provided on the air introduction side and a second straightening vane provided on the exhaust side from the first straightening vane.
The first straightening vane is provided at a position corresponding to the introduction port, and has an inclined plate that is bent toward the holes at both ends in the longitudinal direction of the second straightening vane, and the inclined plate has a plurality of fine particles. A hole is formed,
The dust collector according to claim 6, wherein the holes of the second straightening vane are formed so as to have a larger diameter toward both ends in the longitudinal direction. An electrode support member that electrically contacts the internal electrode and supports the plurality of discharge electrodes is provided, the high-voltage power supply applies a high voltage to the internal electrode via the electrode support member, and the electrode support member The dust collector according to any one of claims 4 to 7, which is attached to the exhaust side of air containing a desorbed odorous substance flowing through the discharge electrode.

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