JPH02107362A - Electric precipitator - Google Patents

Abstract

PURPOSE:To enhance dust collection efficiency by using a three-dimensional reticulated iron porous body in a dust collection electrode or in both of discharge electrode and the dust collection electrode and allowing dust-containing gas to flow through said three-dimensional reticulated iron porous body from the discharge electrode to the dust collection electrode. CONSTITUTION:A three-dimensional reticulated iron porous body provided with voids having a pore size of 0.1 - 10mm is used in a dust collection electrode 1 or in both of a discharge electrode 2 and the dust collection electrode 1 and dust-containing gas is allowed to flow through the porous body 4 from the discharge electrode 2 to the dust collection electrode 1. As a result, dust collection efficiency becomes high and this constitution can be adapted to a small- sized electric precipitator. Further, collected dust can be easily removed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is based on 'r1. This article relates to an electrostatic precipitator that collects loose dust. For collecting dust from internal combustion engine exhaust gas and purifying indoor air,
It is desirable to have an electrostatic precipitator that is small and has high dust collection efficiency, and in these small electrostatic precipitators, it is preferable that the collected dust deposited on the dust collection electrode can be easily removed.

The present invention can also be applied to small-sized electrostatic precipitators.

The present invention relates to an electrostatic precipitator that has high dust collection efficiency and can easily remove collected dust.

[Conventional technology] FIG. 3 is a diagram showing an example of a conventional electrostatic precipitator.

An electrostatic precipitator is a device that charges dust in a fluid with a negative charge by corona discharge or the like, and then uses a dust collection plate as a positive electrode to adsorb and collect dust using Coulomb force.

Usually, a metal wire or a metal plate is used as the discharge electrode 2, and a metal plate or a metal cylinder is used as the dust collection pole 1. In a large dust collector, the dust collection electrode 1 can be made of a plate with a large area, so dust can be collected! 4 There is a good chance that dust will be removed by adsorption when approaching and touching the electrode plate, but with small dust collectors, the dust collecting electrode is small and the chance of adsorption and removal of dust is extremely short, making it difficult to increase dust collection efficiency sufficiently. .

Furthermore, in an electrostatic precipitator, when the collected dust accumulates on the collecting electrode, the corona discharge current decreases and the dust collection efficiency decreases. Conventionally, the removal of dust adhering to the dust collecting electrode has been carried out using a hammer vibration method or a water washing method, but these methods of removing accumulated dust require large-scale equipment and the work to remove accumulated dust is cumbersome. be.

In the top view, 8 is a power source for dust collection.

[Problems to be Solved by the Invention] The present invention solves the problem of reducing the dust capture rate when using a small dust collection plate, for example, by minimizing the distance between the dust and the dust collection electrode plate to maximize the Coulomb force. The present invention discloses a compact electrostatic precipitator that can be used for a limited time, increases the chance of collision with a precipitate electrode plate, and uses a filter effect to greatly improve the capture rate. The present invention provides a compact electrostatic precipitator that can simplify the conventional water washing, backwashing, and hammering vibration methods by using electrical heating as necessary.

[Means and operations for solving the problems] FIG. 1 is a diagram showing an example of a dust collector according to the present invention.

In the present invention, a three-dimensional mesh iron porous body 4 (hereinafter referred to as "a") is provided in the dust collection electrode 1 or in the discharge electrode 2 and the collection S electrode 1.

The dust-containing gas 3 is caused to flow through the barbed hole. Collection! 4 When a barbed wire body is used as the electrode, the distance between the dust and the dust collecting electrode (skeleton of the barbed barbed body) is shortened, and the electrode area increases, and the charged dust in the gas flow passing through the barbed hole body is reduced. The dust aggregates and accumulates in the vortex region generated in each part of the skeleton of the barbed hole body, increasing the dust collection efficiency.

In addition, even if the dust collecting electrode 1 is made of a barbed hole, the surface area of the skeleton forming the barbed hole is large, so the thickness of the accumulated layer of trapped dust is thin, and therefore the discharge current is also small. It is stable and the frequency of removing accumulated dust can be reduced.

When the barbed hole body 4 is used as a discharge electrode, the discharge electrode acts as a filter and the coarse dust of the dust-containing gas 3 is removed here, so the dust collection load on the dust collection electrode 1 is reduced and the dust collection efficiency is improved. It gets expensive.

In claim (2) of the present invention, the diameter of the pores is 0.1-10
A wire hole body of mm is used. FIG. 2 is a diagram showing an example of the barred hole body of the present invention. In the wire hole body, an iron skeleton 5 forms holes 6.

When the diameter of the holes 6 is 0.1+am or less, the dust collection efficiency is good, but it becomes difficult to remove the dust attached to the holes 6, and the holes are likely to become clogged. In addition, in a bar body in which the diameter of the hole 6 is 10 mm or more,
The number of holes 6 is small, and the electrode area formed by the skeleton 5 of the barbed hole body is small, so that the effect of the present invention is small.

According to claim (3) of the present invention, the electrode of the barbed hole body is provided with an energization heating device 7 for heating the barbed hole body in order to burn dust. Dust adhering to the electrodes can be removed by vibration or washing with water, but the easiest way to remove dust is by burning it. For example, when cleaning indoor air, dust containing a large amount of unburned carbon and unburned hydrocarbons is captured, but these dusts are combusted by heating the ffi electrode of the barbed hole body with electricity. can be easily removed.

An oxidation catalyst, such as Pt or Pd, is provided on the surface of the skeleton 5 of the barbed hole body.
.

If Rh or the like is applied, combustion removal of dust becomes easier.

The heating device 7 for the wire hole body may be a direct current heating method or an induction heating method.

Claim (4) of the present invention is iron oxide powder and surface oxidized iron powder.

This invention uses, as a porous body for an electrode, a barred porous body manufactured using a powder containing one or more of iron powders. Iron is an inexpensive good conductor, and iron oxide or iron with a carbon content of 2.1% or more can be easily crushed, so powder can be produced at low cost. Surface oxidized iron powder is, for example, iron powder that has been wet-ground and has an oxidized surface, but it can be manufactured at low cost like iron oxide powder or iron powder.

These iron-containing powders are mixed with carbon powder or alloy powder as needed to form a mixed powder. The mixed powder is kneaded with an aqueous binder such as CMC, polyacrylic acid, or water glass. The kneaded material is applied to the bones of a three-dimensional organic network, such as urethane foam. When the particle size of the mixed powder is adjusted to 50 μm or less, the kneaded material becomes a slurry and is easily applied to the bones of the urethane foam. This application can be performed by a spray method, a dipping method, or a roll skies method. For example, urethane foam is available in different bubble diameters and bone thicknesses, so choose one as appropriate.

With the barred hole body shown in FIG. 2, it is possible to obtain a barred hole body in which the iron skeleton 5 has a desired thickness and the holes 6 have a desired diameter. The urethane foam coated with the kneaded material is fired in a heat treatment furnace, but the bones of the urethane foam will thermally decompose and disappear at approximately 300°C, and when further heated to 800-1200°C, the coated kneaded material will be baked. The iron skeleton 5 forms the pores 6 by a sintering reaction or by a sintering reaction involving self-reduction between the oxygen and carbon contained. A barred hole body is obtained. This wire hole body may be used as it is as an ffi electrode, but if the skeleton 5 is coated with a metal coating with excellent corrosion resistance by deplating 11, etc., it becomes a wire hole electrode with excellent corrosion resistance. In addition, when adjusting the mixed powder described above, if the mixed powder is adjusted to have a stainless steel component, for example, a wire hole electrode with excellent corrosion resistance can be obtained without applying a corrosion-resistant metal coating to the skeleton 5.

The skeleton 5 of the wire hole body for the discharge electrode preferably has a surface with sharp edges, and the surface of the skeleton 5 for the dust collection electrode is preferably smooth so that the accumulated dust can be easily removed. The surface of the skeleton of the barbed hole body can be made rough with sharp edges by, for example, shortening the sintering time, or it can be made smooth by, for example, oversintering.

[Example] Surface oxidized iron powder (average particle size: top
, C: 3.5%, Si: 0.1%, Mn:, 0.
5%, P: 0.01%, S: 0.01%, O: 6%), 2% by weight of nickel powder with an average particle size of 5μ, and 10% by weight of ferrochrome powder to make a mixed powder. The mixed powder is kneaded with a binder (CMC and water), and urethane foam (100
After painting on m+mX 200noa X 10m5+),
Heat treatment was performed to produce a heat-resistant wire hole body with a hole diameter of about 2 mm. This wire hole body was used as each electrode shown in Table 1, and the collection Ia! When a test was conducted using a power source of 100 V (50 Hz) and a discharge voltage of ±8000 V using a multi-stage voltage doubler method, good results were obtained as shown in the table. This is about 175 times the size of conventional dust collectors, and it was possible to burn off the adhering dust without washing it with water.

[Effects of the Invention] According to the present invention, a dust collector with high dust collection efficiency can be manufactured. The present invention can be applied to a small-sized electrostatic precipitator, and the collected dust can be easily removed.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an example of a dust collector according to the present invention, FIG. 2 is a diagram showing an example of a barred hole body of the present invention, and FIG. 3 is a diagram showing an example of a conventional electrostatic precipitator. 1: N collecting electrode, 2: discharge electrode, 3: dust-containing gas, 4: barbed hole body, 5: skeleton of barbed hole body, 6: void, 7 double current heating device, 8: power source for dust collection. Figure 1 Figure 3 Figure 2 (1-stage type) (2-stage type) (x70) "Procedural Correction Team" l January 1989 310

Claims (4)

[Claims] (1) In an electrostatic precipitator that collects suspended dust by charging it, a three-dimensional mesh iron porous body is used for the dust collection electrode or the discharge electrode and the dust collection electrode, and the dust-containing gas is collected in the three-dimensional An electrostatic precipitator characterized by allowing the flow to flow from the discharge electrode side to the dust collection electrode side by passing through a mesh iron porous body. (2) The three-dimensional mesh iron porous body has pores with a diameter of 0.1 m.
Claim (
The electrostatic precipitator according to 1). (3) The electric dust collector according to claim (1) or (2), wherein the three-dimensional mesh iron porous body of the dust collection electrode is equipped with an energization heating device that burns the adsorbed dust particles. Device. (4) The three-dimensional mesh iron porous body is made by kneading powder containing one or more selected from iron oxide powder, surface oxidized iron powder, and iron powder with a binder, and then kneading the kneaded product into an organic three-dimensional network structure. Claim (1) or (2) or (3) is a three-dimensional mesh porous iron body, which is applied to the bone part of the body, and is heat-treated and sintered.
) The electrostatic precipitator described in ).