JPH11309384A - Electrostatic precipitator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic precipitator in which, even if the same is miniaturized, such time is made long that gas for treatment flows through an electric field and sufficient dust collection is enabled even for gas containing dust of high resistivity. SOLUTION: The electrostatic precipitator 1 is equipped with a cylindrical external electrode 2 provided with both an opening on the inflow side of gas for treatment and an opening on the outflow side of gas for treatment and equipped with an internal electrode 3 which is held in the inside of the cylindrical external electrode 2 and extended from the inflow side of gas for treatment toward the outflow side of gas for treatment in the nearly center of the external electrode 2. The external electrode 2 is a cylindrical conductor having nearly same inside diameter. The internal electrode 3 is equipped with a part 31a on the inflow side of gas for treatment which is constituted of a linear conductor 31 and equipped with a part 32 on the outflow side of gas for treatment which is constituted of a rodlike body or a cylindrical body having an outside diameter larger than the linear conductor 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic precipitator for collecting particulate contaminants in a gas (processing gas) by the action of static electricity, and more particularly to a compact electric precipitator suitable for cleaning indoor air. Related to the device.

[0002]

2. Description of the Related Art Conventionally, a high DC voltage is applied between a discharge electrode and a dust collection electrode to generate corona discharge to charge particulate contaminants, and then collect the dust at the collection electrode by Coulomb force. Electric precipitators are widely used. As such an electrostatic precipitator, an industrial electric precipitator and an air purifying electric precipitator have been proposed. As a dust collector for air cleaning, there is a two-stage flat dust collector formed of a flat plate having a discharge electrode and a dust collection electrode arranged in parallel. In this dust collecting device, the gap between the discharge electrode and the dust collecting electrode is set to several millimeters to several tens of millimeters in order to increase the collection rate at the dust collecting electrode. There is also an electric precipitator in which a linear electrode and a planar precipitating electrode are combined. When a negative DC high voltage is applied to the discharge electrode, a negative corona discharge occurs between the discharge electrode and the dust collection electrode. Then, electrons and negative ions flow from the discharge electrode toward the dust collection electrode. Further, a DC high-voltage electric field is formed in the dust collecting space between the discharge electrode and the dust collecting electrode. When dust is introduced into the dust collecting space, the dust is negatively charged by collision of electrons and negative ions, and adheres and accumulates on the surface of the dust collecting electrode by the action of Coulomb force. The gas from which the dust has been removed passes through the dust collecting space and is discharged out of the electric dust collecting device.

[0003]

However, in the conventional air precipitating apparatus for cleaning air, the smaller the size of the apparatus, the shorter the residence time of the treated gas in the electric field and the insufficient the charging. In particular, when high-resistivity dust is contained, sufficient dust collection may not be performed. SUMMARY OF THE INVENTION An object of the present invention is to provide an electric dust collecting apparatus which has a long residence time of a processing gas in an electric field even if it is miniaturized, and is capable of sufficiently collecting dust even in a gas containing high resistivity dust. It is.

[0004]

The above object is achieved by a cylindrical external electrode having a processing gas inflow side opening and a processing gas outflow side opening, housed in the cylindrical external electrode,
And an internal electrode extending substantially at the center of the external electrode from the processing gas inflow side to the processing gas outflow side, wherein the electrostatic precipitator is provided on the processing gas inflow side. A first processing unit that has a wide space between the internal electrode and the external electrode, and is continuous with the first processing unit;
An electrostatic precipitator including a second processing unit on the outflow side of the processing gas and between the internal electrode and the external electrode that is narrower than the first processing unit.

In order to achieve the above object, a cylindrical external electrode having a processing gas inflow side opening and a processing gas outflow side opening is housed in the cylindrical external electrode. An internal electrode extending substantially from the processing gas inflow side to the processing gas outflow side, wherein the external electrode is a cylindrical conductor having substantially the same inner diameter, and the internal electrode is An electrostatic precipitator comprising: a processing gas inflow side portion formed by a linear conductor; and a processing gas outflow side portion formed by a rod-shaped conductor or a cylindrical conductor having an outer diameter larger than the linear conductor. is there.

The processing gas outflow side portion of the internal electrode has a smooth surface without edges, and the gas inflow side end of the processing gas outflow side portion is formed of the processing conductor formed by the linear conductor. It is preferable that the tapered shape or the hemispherical shape is reduced in diameter toward the use gas inflow side portion. Further, the electrostatic precipitator has an inflow-side cylindrical insulating member attached to the gas-inflow-side opening of the cylindrical external electrode, and allows the flow of the processing gas while being held by the inflow-side cylindrical insulating member. An inflow-side internal electrode holding plate,
An outflow-side cylindrical insulating member attached to the gas-outflow-side opening of the cylindrical external electrode, and an outflow-side internal electrode holding plate that is held by the outflow-side cylindrical insulating member and allows the flow of the processing gas. Preferably, it is provided. Further, the gas inflow side end of the internal electrode is held by the inflow side internal electrode holding plate and located inside the inflow side tubular insulating member, and the gas outflow side end of the internal electrode is connected to the outflow side electrode. Preferably, it is held by the side internal electrode holding plate and located inside the outflow side tubular insulating member.

Preferably, the linear conductor forming a part of the internal electrode has a spring member attached to a distal end or a proximal end, and the linear conductor is pulled by the spring member. Further, the internal electrode is a cylindrical conductor having a tapered or hemispherical diameter and having a tip end having an opening, a linear conductor penetrating through the cylindrical conductor, and a base end of the linear conductor. A spring member attached to a portion, wherein the electrostatic precipitator has a holding mechanism for holding the tubular conductor and the spring member on the outflow-side internal electrode holding plate, and the inflow of the linear conductor to the inflow-side internal electrode holding plate. It is preferable to provide a holding mechanism for holding the internal electrode holding plate.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an electrostatic precipitator according to the present invention. FIG. 1 is a front view of an embodiment of the electric precipitator of the present invention. FIG. 2 is a plan view of the electric precipitator shown in FIG. FIG. 3 is a bottom view of the electric precipitator shown in FIG. FIG. 4 is a cross-sectional view of FIG.
FIG. 3 is a sectional view taken along line A. FIG. 5 is a sectional view taken along line BB of FIG. FIG. 6 is an explanatory diagram for explaining a state in which a current-carrying wire is attached to the electric precipitator of the present invention.

An electrostatic precipitator 1 of the present invention has a cylindrical external electrode 2 having a processing gas inlet side opening and a processing gas outlet side opening, and is housed in the cylindrical external electrode 2 and has an external electrode 2.
And an internal electrode 3 extending substantially at the center from the gas inflow side to the gas outflow side. The electrostatic precipitator 1 includes a first processing unit 21 that is on the gas inflow side and has a wide space between the internal electrode 3 and the external electrode, and is continuous with the first processing unit 21 and is on the gas outflow side and has an internal electrode 3 First processing unit 2 between external electrodes
And a second processing unit 22 smaller than one.

The electric dust collecting apparatus 1 of the present invention has a cylindrical external electrode 2 having a processing gas inflow side opening and a processing gas outflow side opening, and is housed in the cylindrical external electrode 2 and externally. An internal electrode 3 extending substantially from the center of the electrode 2 toward the processing gas outflow side from the processing gas inflow side, and the external electrode 2 is a cylindrical conductor having substantially the same inner diameter; 3 includes a processing gas inflow side portion 31a constituted by a linear conductor 31 and a processing gas outflow side portion 32 constituted by a rod-shaped or cylindrical conductor having an outer diameter larger than that of the linear conductor 31. Is what it is.

In the electrostatic precipitator 1, since the internal electrode 3 and the external electrode 2 are parallel to the flow direction of the processing gas, the distance that the processing gas comes into contact with the electrode is long, and the fine particles in the gas are charged. And the first processing unit 21 (processing gas inflow side portion 31a) on the upstream side
The second processing section 22 (processing gas outflow side portion 32) on the downstream side has a narrow gap between the internal electrode and the external electrode and the electric field on the dust collection electrode side is strengthened, so the first processing section 21 (processing gas inflow side portion). 3
The fine particles charged in 1a) are surely attracted to the external electrode 2 by the second processing section 22 (the processing gas outflow side portion 32), so that better dust collection can be performed.

As shown in FIGS. 1 and 4, the electric dust collecting apparatus 1 of this embodiment has a cylindrical external electrode 2, an internal electrode 3 housed in the cylindrical external electrode 2, and a cylindrical external electrode 2. 2, an inflow-side cylindrical insulating member 4 attached to the gas inflow-side opening;
An inflow-side internal electrode holding plate 6 held by the inflow-side cylindrical insulating member 4, an outflow-side cylindrical insulating member 5 attached to a gas outflow-side opening of the cylindrical external electrode 2, and an outflow-side cylindrical insulating member 5 And an outflow-side internal electrode holding plate 7 held at a predetermined position.

As shown in FIGS. 4 and 5, the cylindrical external electrode 2 is a cylindrical body having a processing gas inflow side opening and a processing gas outflow side opening. The cylindrical external electrode 2 is preferably a cylindrical conductor, but may be a polygonal cylindrical body (for example, hexagonal or octagonal). In particular, in this embodiment, a cylindrical conductor (cylindrical body) having a uniform inner diameter and outer diameter is provided. Further, the cylindrical external electrode 2 is formed of a conductive material. As the conductive material, any material may be used,
For example, those having high corrosion resistance such as stainless steel and aluminum are suitable. Further, it is also preferable that the inside is made of a metal such as stainless steel, stainless steel, or aluminum having a mirror-finished surface, and the inner surface is covered with a fluororesin or insulating paper or film. In particular, when an alternating current is applied to the dust collector, the dust collector is preferably covered with the above-mentioned fluororesin or insulating film.

The internal electrode 3 is housed in the cylindrical external electrode 2 and extends substantially at the center of the external electrode 2 from the gas inflow side opening to the gas outflow side opening. In this embodiment, as shown in FIG. 4, the internal electrode 3 has a cylindrical conductor 32 having a tapered or hemispherical diameter and having a tip end having a small opening in the center, and a cylindrical conductor through the opening. It is constituted by a linear conductor 31 penetrating inside the conductor 32.
The processing gas inflow side portion 31a of the internal electrode 3 is constituted by the portion of the linear conductor 31 exposed in the external electrode 2, and the cylindrical conductor 32 having a larger outer diameter than the linear conductor 31.
This constitutes the processing gas outflow side portion of the internal electrode 3. For this reason, the inside of the electrostatic precipitator 1 is on the processing gas inflow side, the internal electrode and the external electrode are wide, and the first processing unit 21 extending in the predetermined long axis direction;
And a second processing section 22 which is on the processing gas outflow side, between the internal electrode and the external electrode, is narrower than the first processing section 21 and extends in a predetermined long axis direction.

Further, a spring member 33 housed in the cylindrical conductor 32 is attached to the base end of the linear conductor 31. The electrostatic precipitator 1 includes a holding mechanism 9 for holding the cylindrical conductor 32 and the spring member 33 on the outflow-side internal electrode holding plate 7 and a tip end of the linear conductor 31 on the inflow-side internal electrode holding plate. It has a holding mechanism 8 for holding.

As the linear conductor 31, a conductive material is used, for example, a tungsten wire or a stainless steel wire is preferable, and for the cylindrical conductor 3, for example, stainless steel is preferable. Further, as the material for forming the linear conductor 31 and the cylindrical conductor 32, it is preferable to use a material having as small an electric resistance as possible. Further, the processing gas outflow side portion of the internal electrode 3, in other words, the distal end portion of the cylindrical conductor 32 has, as shown in FIGS. 4 and 5, an edge except for a central opening through which the linear conductor 31 passes. It has a smooth surface and a tapered or hemispherical shape whose diameter decreases toward the distal end. For this reason, the cylindrical conductor 3
The spark at the tip of No. 2 is small. further,
The entire outer surface of the tubular conductor 32 located in the external electrode 2 also has a smooth surface without edges,
They have almost the same outer diameter.

An inflow-side cylindrical insulating member 4 is attached to the gas-inflow-side opening of the cylindrical external electrode 2. Similarly, the outflow-side cylindrical insulating member 5 is provided at the gas outflow-side opening of the cylindrical external electrode 2.
Is attached. The inflow-side cylindrical insulating member 4 has an annular groove 4 a for accommodating the gas inflow-side opening of the cylindrical external electrode 2. Similarly, the outflow-side cylindrical insulating member 5 has a gas outflow side of the cylindrical external electrode 2. An annular groove 5a for accommodating the opening is provided. The inflow-side cylindrical insulating member 4 has an annular groove 4b at the upper end for accommodating the inflow-side internal electrode holding plate, and the outflow-side cylindrical insulating member 5 has an annular groove at the lower end for accommodating the outflow-side internal electrode holding plate. 5b. These tubular insulating members 4 and 5 are formed of an insulating material such as a hard or semi-hard synthetic resin or ceramics. As synthetic resins, for example, polyvinyl chloride (hard vinyl chloride), polycarbonate,
An acrylic resin (for example, polyacrylate), a styrene-based resin (for example, polystyrene), or the like can be used.

The distal end of the linear conductor 31 is held on the inflow-side internal electrode holding plate 6 by the holding mechanism 8, and the spring member 33 and the tubular conductor 32 attached to the rear end of the linear conductor 31 The holding mechanism 9 holds the outflow-side internal electrode holding plate 7. The internal electrode holding plates 6, 7 on the inflow side and the outflow side are provided with a large number of openings 6a, 7a, as shown in FIGS. 2, 3, 4, and 5, so that the processing gas can flow. In other words, the opening 6a of the inflow-side internal electrode holding plate 6 forms an inlet for the processing gas, and the opening 7a of the outflow-side internal electrode holding plate 7 forms an outlet for the processing gas.

The holding mechanism 8 has a holding member 81 having a passage for inserting the distal end portion of the linear conductor 31 extending upward from the center of the flange-like bottom and reaching the side surface, and formed on the side surface of the holding member 81. A fixing member 82 having a female screw portion to be screwed with the male screw portion is provided. The front end of the linear conductor 31 is sandwiched between the holding member 81 and the fixing member 82 by holding the front ends of the internal electrode holding plate 6 and the linear conductor 31. To the internal electrode holding plate 6
It is fixed to. To facilitate disassembly and cleaning,
The internal electrode holding plate 6 is not fixed to the inflow side cylindrical insulating member 4. The internal electrode holding plate 6 to which the distal end of the linear conductor 31 is fixed is pulled toward the internal electrode holding plate 7 by the contraction force of the spring, so that the inflow side cylindrical insulating member 4 is formed.
Is held in.

As described above, since the linear conductor 31 used for the internal electrode 3 is held by the spring member 33, it does not bend even if the linear conductor 31 expands due to heating during use. There is no deflection due to deflection.

The holding mechanism 9 includes a bolt 91, a washer 95, a nut 94, and a fixing member 92 having a female screw portion to be screwed with the bolt 91. At the rear end of the spring member 33, a spring holding member 93 is provided.
Further, a female screw portion that is screwed with a male screw portion formed on the side surface of the fixing member 92 is formed on the inner surface of the rear end of the cylindrical conductor 32. Further, a female screw portion to be screwed with a male screw portion formed on the rear end side surface of the spring holding member 93 is formed at the tip of the bolt 91. The rear end of the tubular member is fixed to the tip of the bolt 91 via a spring holding member 93 and a fixing member 92. The rear end of the internal electrode 3 is fixed to the internal electrode holding plate 7 by holding the internal electrode holding plate 7 between the nut 94 and the washer 95 with the bolt 91 and the nut 94. Note that the internal electrode holding plate 7 is not fixed to the outflow-side tubular insulating member 5 to facilitate disassembly and cleaning. The internal electrode holding plate 7 to which the tubular conductor 32 is fixed is held by the outflow side tubular insulating member 5 by being pulled toward the internal electrode holding plate 6 by the contraction force of the spring.

The rear end of the cylindrical conductor 32 is located in the outflow side cylindrical insulating member 5 and is held with a sufficient insulating distance, so that no spark is generated at the rear end of the cylindrical conductor 32. Similarly, the tip of the linear conductor 31 is also located in the inflow-side tubular insulating member 4, and there is no spark at the tip of the linear conductor 31.

The length of the cylindrical external electrode 2 is 200 to 200.
About 500 mm is preferable, and particularly, 200 to 300 m
About m is preferable. As the inner diameter of the cylindrical external electrode 2,
About 40 to 60 mm is preferable, and in particular, 40 to 50 m
About m is preferable. As the wire diameter of the linear conductor 31,
About 0.1 to 1.0 mm is preferable, and especially 0.3 to 1.0 mm.
About 0.5 mm is suitable. In addition, the length of the portion of the linear conductor 31 exposed in the external electrode 2 (in other words, the length of the first processing unit 21 on the processing gas inflow side and wide between the internal electrode 3 and the external electrode) is used. Is 100-250m
About m is preferable, and about 200 to 250 mm is particularly preferable. In addition, the length of the portion of the cylindrical conductor 32 exposed in the external electrode 2 (in other words, the length of the second processing unit 22 that is on the processing gas outflow side and is narrow between the internal electrode and the external electrode) is , 50 to 200 mm is preferable,
In particular, about 100 to 150 mm is preferable. further,
The distance between the cylindrical conductor 32 and the external electrode is preferably about 10 to 20 mm, and particularly preferably about 10 to 15 mm. Further, the ratio of the length of the first processing unit 21 to the length of the second processing unit 22 is preferably about 1: 1 to 3: 1, and in particular, 2: 3.
About 1-3: 1 is suitable.

The current supply mode of the internal electrode 3 may be any type as long as current is supplied to both the linear conductor 31 and the cylindrical conductor 32 by a current supply line connected to one of the fixing means 8 and 9. Such a thing may be used. For example, bolt 9
1. It is conceivable that the fixing member 92, the spring holding member 93, and the spring member 33 are formed of a conductive material, and both the linear conductor 31 and the tubular conductor 32 are directly energized. 32 and the linear conductor 31 do not need to be in contact with each other, and the linear conductor 31 may be inserted through the opening at the tip of the cylindrical conductor 32 without contacting the cylindrical conductor 32.
In addition, the fixing member 92 is formed of an insulating material, and the linear conductor 31 is formed at the tip end opening of the cylindrical conductor 32.
, And the tubular conductor 32 may be energized through the linear conductor 31.

Since the dust collecting apparatus 1 is a single cylindrical object, the capacity can be freely designed depending on the inner diameter and the number of the cylindrical objects, so that the dust collecting apparatus 1 can be applied to any size of the dust collecting object. it can. Further, when cleaning the dust collecting device 1, the dust collecting device may be removed from the dust collecting facility and replaced with a new or washed dust collecting portion, and there is no need to disassemble and clean the entire dust collecting facility. Further, in the dust collecting apparatus of the present invention, by applying an alternating current, it is possible to easily process a gas containing high resistivity dust such as dust containing a large amount of oil (for example, oil mist). By applying the
Contaminated gas containing low resistivity dust can be treated. Further, by applying a DC negative polarity discharge application having a high generation efficiency of negative ions, it is possible to perform a gas treatment that requires odor removal, sterilization and sterilization. In this dust collector, it is possible to perform a desired gas treatment only by changing the mode of applying electricity without making any special changes.

As shown in FIG. 6, the energizing wires 35 and 96 are connected to the dust collecting apparatus 1 of the present invention at the time of use.
In the embodiment shown in FIG. 6, the first energizing line 35 includes a curved metal plate 36 at the tip, and the metal plate 36
7a and 37b make close contact with the outer surface of the external electrode 2. The band allows a metal plate of the conducting wire to be attached to the external electrode 2 and its release by operation from the outside of the external electrode 2. The second energizing wire 96 has an arc-shaped metal member 97 at the end, and the metal member is sandwiched between the bolt 91 and the washer 95. The arc-shaped metal member 9
7 is provided with a cut-out portion that can be inserted between the bolt 91 and the washer 95 from the side surface of the bolt 91, so that it can be easily attached to and removed from the dust collecting device 1. With this configuration, the dust collection device 1 can be attached and detached to and from the dust collection device 1.
It is not necessary to disassemble the dust collecting device, and it is easy to remove the dust collecting device 1 from the dust collecting facility.

In the above-described dust collector 1, the spring member 33 is attached to the rear end of the linear conductor 31 and is housed in the cylindrical conductor 32. However, the present invention is not limited to this. A spring member 33 may be provided at the tip of the linear conductor 31 so as to be located in the side cylindrical insulating member 4.

As the internal electrode 3, the above-mentioned one is preferable. For example, as shown in a dust collecting device 40 shown in FIG. 7, a linear conductor portion 41 a and a rod-shaped or cylindrical body portion 41 b (this In the embodiment, a rod-shaped body) may be integrally formed. In this case, the rod-shaped or cylindrical body portion 41
At the rear end of b, a female screw portion for screwing the male screw of the bolt 91 is formed.

The dust collector may have a structure as shown in FIG. In this dust collector 50,
The inflow-side cylindrical insulating member 4 and the outflow-side cylindrical insulating member 5 are
It has annular concave portions 44C and 45C. Such an annular concave portion forms a portion where the substance in the processing gas and the dust collecting substance hardly adhere to each other, so that a short circuit due to the conductivity of the attached substance can be suppressed.

Next, the dust collector 1 shown in FIGS.
00 will be described. FIG. 9 is a front view of another embodiment of the electric precipitator of the present invention. FIG. 10 is a plan view of the dust collection device shown in FIG. FIG. 11 is a cross-sectional view taken along line CC of the dust collecting apparatus shown in FIG.

The dust collecting apparatus 100 has the same basic configuration as the above-described dust collecting apparatus 1, and the same parts are denoted by the same reference numerals, and the above description is referred to. The electric precipitator 100 includes two frame members 1 facing each other.
01 and 102 are provided. These two frame members 10
An upper member 108 having a cylindrical port for connection to a blower (not shown) is fixed to the upper end of the first and second members 102.
An internal electrode holding member attaching member 1 for attaching a narrow plate-like inflow-side internal electrode holding member 116 is provided at a position below the upper ends of the frame members 101 and 102 by a predetermined distance.
12a and 112b are fixed. Further, an inflow-side cylindrical insulating member holding portion 106 for holding the inflow-side cylindrical insulating member 104 is fixed at a position below the electrode holding member mounting members 112a and 112b. As shown in FIG. 11, the holding portion 106 is provided with the inflow-side tubular insulating member 1.
04 has a circular opening that is the same as or larger than the small diameter portion and smaller than the large diameter portion. The small-diameter portion of the inflow-side cylindrical insulating member 104 is substantially the same as the inner diameter of the cylindrical external electrode 2, and its end is fitted into the end of the cylindrical external electrode 2.

Similarly, a lower member 109 having a cylindrical port is fixed to the lower ends of the frame members 101 and 102. Further, internal electrode holding member mounting members 113a and 113b for mounting the plate-shaped outflow side internal electrode holding member 117 are fixed at positions above the lower ends of the frame members 101 and 102 by a predetermined distance. Further, an inflow-side cylindrical insulating member holding portion 107 for holding the outflow-side cylindrical insulating member 105 is fixed at a position above the electrode holding member mounting members 113a and 113b. As shown in FIG. 11, the holding portion 107 has a circular opening that is the same as or larger than the small diameter portion of the outflow side tubular insulating member 105 and smaller than the large diameter portion. The small-diameter portion of the outflow-side cylindrical insulating member 105 is substantially the same as the inner diameter of the cylindrical external electrode 2, and its end is fitted into the end of the cylindrical external electrode 2.

The frame members 101 and 102, the insulating member holding portions 106 and 107, and the cylindrical insulating members 104 and 105
It is formed of an insulating material such as a hard or semi-hard synthetic resin or ceramics. As the synthetic resin, for example, polyvinyl chloride (hard vinyl chloride), polycarbonate, acrylic resin (for example, polyacrylate), styrene-based resin (for example, polystyrene) can be used.

In the dust collector 100,
A cylindrical external electrode 2 having a processing gas inflow side opening and a processing gas outflow side opening, and housed in the cylindrical external electrode 2 and having substantially the center of the external electrode 2 directed from the gas inflow side to the gas outflow side; And an internal electrode 3 extending therefrom. Electric dust collector 1
Is a first processing unit 21 that is on the gas inflow side and has a wide gap between the internal electrode 3 and the external electrode, and is continuous with the first processing unit 21, and is on the gas outflow side and has a third space between the internal electrode 3 and the external electrode. A second processing unit 22 that is narrower than the first processing unit 21;

A weight 110 is attached to the distal end of the linear conductor 31a constituting the internal electrode 3 in order to facilitate hooking into a hole provided substantially at the center of the internal electrode holding member 116. Then, the hook fixed to the tip of the weight is hooked into the hole of the internal electrode holding member 116, so that the tip of the linear conductor 31a is held by the internal electrode holding member 116. Note that the external electrode 2, the internal electrodes 31, 32, and the like are the same as those in the dust collector 1 described above.

In this dust collecting apparatus 100, as shown in FIG. 9, a portion where both ends of the internal electrode are located, in other words, a portion above the cylindrical insulating member 104 and a portion below the cylindrical insulating member 105 are open system. It has become. That is, in this dust collecting apparatus 100, the end (tip) of the internal electrode 31a is
It protrudes from the external electrode and the cylindrical insulating member 104 and is exposed. Similarly, the end (rear end) of the internal electrode 32 is also projected and exposed from the external electrode and the tubular insulating member 105.
For this reason, the substances in the processing gas and the dust-collecting substances are extremely unlikely to adhere to the inner walls of the dust-collecting device (the inner walls of the frames 101 and 102) where the electrodes are exposed, and the short-circuit caused by the adhering substances is more reliably caused. Can be suppressed.

Then, a power supply device as shown in FIG. The power supply device of this embodiment includes a primary power supply, a control circuit, a voltage / frequency adjusting device, a step-up transformer, a half-wave or full-wave rectifier circuit, and the like. A half-wave or full-wave rectified wave is applied between the conducting wires 35 and 96 (in other words, between the external electrode 2 and the internal electrode 3). The internal electrode 3
Is connected to the minus side and the external electrode 2 is connected to the plus side.

The operation of the electric precipitator 1 to which such a power supply device is connected will be described. When a rectified wave is applied between the external electrode 2 and the internal electrode 3 by the power supply device,
The dust collector 1 operates. The electric precipitator 1 of this embodiment is used so that the axis of the cylindrical electrode is in a vertical or inclined state as shown in FIG. When a blower (not shown) is driven, room air is introduced into the first processing unit 21 inside the dust collector 1 from above the dust collector 1. External electrode 2
An electric field is formed between the internal electrode 3 and the internal electrode 3, a negative corona discharge is generated in the internal electrode (discharge electrode) 3, and electrons and negative ions flow toward the external electrode 2.

When electrons and negative ions collide with dust particles in the introduced air, the dust particles are negatively charged. Some of the negatively charged dust particles (existing near the external electrode) are attracted to the external electrode 2 connected to the positive side by the action of Coulomb force and move. Further, part of the negatively charged dust particles (existing near the internal electrodes) passes through the first processing unit 21 and passes through the second processing unit 22.
The dust in the processing gas is removed by moving toward the external electrode 2 by being attracted to the external electrode (dust collection electrode) 2 connected to the plus side by the action of Coulomb force. You. In addition, the external electrode 2
The dust particles adhering to the inner wall of the outer electrode 2 absorb the moisture and oil in the air to be fluidized, and the external electrode 2 is arranged in a vertical or inclined state. To move down. The air from which dust has been removed flows out of the dust collector 1.

Further, a high-voltage AC power supply may be used as the power supply. For example, when a single-phase AC is used as an AC power supply, an AC unequal electric field is formed between the external electrode 2 and the internal electrode 3. Dust and mist in the processing gas alternately charge + and-charges, causing active reciprocating motion between the electrodes. Due to the collision of the dust and mist, agglomeration of particles of 0.1 micron or less is caused. Promote and increase dust collection efficiency. Further, the aggregates of the dust collection electrode (external electrode) flow down naturally, thereby preventing early contamination of the dust collection electrode. In particular, in the present invention, charging is assured because the upstream side is wide, and the internal space on the downstream side is narrow, so that Coulomb force works strongly and aggregation due to collision of dust and mist is further promoted, so that its removal is also reliable. Becomes By using such an AC power supply device, the cost of the entire device can be reduced as compared with the case of using a DC high-voltage power supply device. Further, since the amount of dust attached to the inner surface of the external electrode 2 is small, the cleaning cycle (replacement cycle) of the dust collector 1 can be lengthened. As shown in FIG. 13, the dust collector 1 to which the AC power supply 75 is connected
And the dust collector 1 to which the high-voltage DC power supply 70 is connected. The applied voltage varies depending on the diameter of the external electrode, but is preferably in the range of 7 to 20 kV irrespective of DC or AC.

[0041]

According to the present invention, there is provided an electrostatic precipitator having a tubular external electrode having a processing gas inlet side opening and a processing gas outlet side opening, housed in the cylindrical external electrode, and provided with the external electrode. And an internal electrode extending substantially from the processing gas inflow side to the processing gas outflow side, wherein the electrostatic precipitator is on the processing gas inflow side and the internal A first processing unit having a wide space between the electrode and the external electrode, the first processing unit being continuous with the first processing unit, and being on the processing gas outflow side and having a gap between the internal electrode and the external electrode, A narrow second processing unit.

Further, the electric dust collecting apparatus of the present invention comprises a cylindrical external electrode having a processing gas inflow side opening and a processing gas outflow side opening, housed in the cylindrical external electrode, and provided with the external electrode. An internal electrode extending substantially from the center toward the processing gas inflow side toward the processing gas outflow side, wherein the external electrode is a cylindrical conductor having substantially the same inner diameter; Has a processing gas inflow side portion composed of a linear conductor, and a processing gas outflow side portion composed of a rod-shaped or cylindrical body having an outer diameter larger than that of the linear conductor.

In this electrostatic precipitator, since the internal electrode and the external electrode are parallel to the flow direction of the processing gas, the distance of contact between the processing gas and the electrode is long, and the fine particles in the gas are reliably charged. And the second processing section (the processing gas inflow side portion) on the upstream side and the second processing section on the downstream side.
In the processing section (portion on the processing gas outflow side), the fine particles charged in the first processing section (portion on the processing gas inflow side) are discharged from the first processing section (portion on the processing gas inflow side) because the distance between the internal electrode and the external electrode is narrow and the electric field on the dust collecting electrode side is strengthened. The suction of the processing section (processing gas outflow side portion) to the external electrode 2 is ensured, so that more favorable dust collection can be performed.

[Brief description of the drawings]

FIG. 1 is a front view of an embodiment of an electric precipitator of the present invention.

FIG. 2 is a plan view of the electric precipitator shown in FIG.

FIG. 3 is a bottom view of the electric precipitator shown in FIG. 1;

FIG. 4 is a sectional view taken along line AA of FIG. 1;

FIG. 5 is a sectional view taken along line BB of FIG. 1;

FIG. 6 is an explanatory diagram for explaining a state in which a current-carrying wire is attached to the electric precipitator of the present invention.

FIG. 7 is a sectional view of another embodiment of the electric precipitator of the present invention.

FIG. 8 is a sectional view of another embodiment of the electric precipitator of the present invention.

FIG. 9 is a front view of another embodiment of the electric precipitator of the present invention.

FIG. 10 is a plan view of the electric precipitator shown in FIG. 9;

FIG. 11 is a sectional view taken along the line AA of FIG. 10;

FIG. 12 is an explanatory diagram for explaining a state in which a power supply is connected to the electric precipitator of the present invention.

FIG. 13 is an explanatory diagram for explaining a state in which a power supply is connected to the electric precipitator of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electrostatic precipitator 2 cylindrical external electrode 3 internal electrode 4 inflow-side cylindrical insulating member 5 outflow-side cylindrical insulating member 6 inflow-side internal electrode holding plate 7 outflow-side internal electrode holding plate 21 first processing unit 22 second Processing part 31 linear conductor 32 tubular conductor 33 spring member

Claims (7)

[Claims] 1. A cylindrical external electrode having a processing gas inflow side opening and a processing gas outflow side opening, and a center of the external electrode housed in the cylindrical external electrode and substantially centered on the processing gas inflow side. An electrostatic precipitator comprising: an internal electrode extending more toward the processing gas outflow side; wherein the electric precipitator is the processing gas inflow side and has a wide space between the internal electrode and the external electrode. A first processing unit and a second processing unit that is continuous with the first processing unit and that is on the processing gas outflow side and that has a narrower gap between the internal electrode and the external electrode than the first processing unit. An electrostatic precipitator characterized by the above-mentioned. 2. A cylindrical external electrode having a processing gas inflow side opening and a processing gas outflow side opening; and a substantially center of the external electrode housed in the cylindrical external electrode and having a processing gas inflow side. An internal electrode extending further toward the processing gas outflow side, wherein the external electrode is a cylindrical conductor having substantially the same inner diameter, and the internal electrode is a processing device formed of a linear conductor. An electrostatic precipitator comprising: a gas inlet side portion for processing; and a processing gas outlet side portion formed of a rod-shaped or cylindrical body having an outer diameter larger than that of the linear conductor. 3. The processing gas outlet side portion of the internal electrode has a smooth surface without edges, and the processing gas outlet side portion of the processing gas outlet side portion is formed by the linear conductor. The electrostatic precipitator according to claim 2, wherein the precipitator has a tapered or hemispherical shape whose diameter is reduced toward a portion of the working gas inflow side. 4. An electric precipitator includes an inflow-side cylindrical insulating member attached to a gas-inflow-side opening of the cylindrical external electrode, a processing gas held by the inflow-side cylindrical insulating member, and a processing gas. An inflow-side internal electrode holding plate permitting flow, an outflow-side cylindrical insulating member attached to a gas outflow-side opening of the cylindrical external electrode, and a processing gas held by the outflow-side cylindrical insulating member. The electrostatic precipitator according to any one of claims 1 to 3, further comprising an outflow-side internal electrode holding plate that allows circulation. 5. The gas inflow side end of the internal electrode is held by the inflow side internal electrode holding plate and located in the inflow side tubular insulating member, and the gas outflow side end of the internal electrode is provided. The electrostatic precipitator according to claim 4, wherein は is held by the outflow-side internal electrode holding plate and is located inside the outflow-side tubular insulating member. 6. A linear conductor constituting a part of the internal electrode has a spring member attached to a distal end or a proximal end, and the linear conductor is in a state of being pulled by the spring member. The electric dust collector according to claim 2. 7. The conductive electrode according to claim 1, wherein the inner electrode has a tapered or hemispherically reduced diameter, and has a tip having an opening; and the linear conductor penetrating through the cylindrical body.
A spring member attached to the base end of the linear conductor and housed in the cylindrical body, wherein the electric dust collecting device attaches the cylindrical body and the spring member to the outflow-side internal electrode holding plate. The electrostatic precipitator according to any one of claims 2 to 6, further comprising a holding mechanism for holding, and a holding mechanism for holding the linear conductor on the inflow-side internal electrode holding portion.