JPH07265731A - Electric precipitator - Google Patents

Abstract

PURPOSE:To provide an electric precipitator capable of efficiently recovering dust by allowing electric fields different in intensity to act on dust in air to be treated without changing voltage. CONSTITUTION:In an electric precipitator consisting of a casing 4 guiding dust- containing air to be treated, the discharge electrodes 5 arranged in the casing 4 so as to be turned in the direction crossing the flow direction of air 1 to be treated and the dust collecting members 6 having a permeation structure of air 1 to be treated and arranged in parallel to the discharge electrodes 5, the discharge electrodes 5 and the dust collecting members 6 are arranged so that the mutual intervals (x), (y), (z) between them become narrow successively in the flow direction of air 1 to be treated. When the same voltage is applied across the discharge electrodes 5 and the dust collecting members 6 to operate the electric precipitator, electric fields different in intensity corresponding to the mutual intervals (x), (y), (z) are formed and dust in air 1 to be treated is successively collected by particle sizes from dust having a large particle size easy to collect in the flow direction of air 1 to be treated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic precipitator, and more particularly to an electrostatic precipitator capable of collecting dust from a processing gas containing dust by particle size.

[0002]

2. Description of the Related Art In an electrostatic precipitator, when a high voltage is applied between a discharge electrode and a dust collecting member, a corona discharge is generated between both parts to form a charge band, and the charge band is processed. The dust contained in the processing gas is charged by flowing the gas, and the charged dust is attracted to and collected by the dust collecting member having the opposite potential.

FIG. 5 is a cutaway plan view showing an example of a conventional electrostatic precipitator, and a casing provided with a gas inflow duct 2 and a gas exhaust duct 3 for guiding a treated gas 1 containing dust in a direction of an arrow. 4, a discharge electrode 5 having a permeation structure of the processing gas 1 and arranged in parallel with the flow direction of the processing gas 1 and formed of a plate-like object having a mesh shape, a discrete line shape, or a protrusion of a thorn, and a mesh shape. Alternatively, a dust collecting member 6 having a structure such as a perforated plate and arranged in parallel with the discharge electrode 5
And are suspended and supported to form a main part of the electrostatic precipitator 7.

Since the discharge electrode 5 and the dust collecting member 6 are arranged in parallel with the flow direction of the processing gas 1 in the electrostatic precipitator 7 having the above-described structure, the charged powder in the processing gas 1 is The dust collecting member 6 is easily sucked and easily flowed without being sucked,
There is a problem in that it is difficult to increase the dust collection efficiency, which causes a problem that the electric dust collector 7 becomes large.

For this reason, in recent years, as shown in FIG. 6, a discharge electrode 5 and a dust collecting member 6 having a permeation structure of the processing gas 1 in a casing 4 in a direction intersecting with the flowing direction of the processing gas 1. An electrostatic precipitator 8 having a structure in which is arranged is considered.

According to this electrostatic precipitator 8, since the discharge electrode 5 and the dust collecting member 6 are arranged in a direction intersecting with the processing gas 1 flowing in the casing 4, dust from the discharge electrode 5 is prevented. By increasing the chances of loading and suctioning dust to the dust collecting member 6, the action of passing dust as in the case of FIG. 5 is reduced, and the dust collecting efficiency can be greatly increased. .

[0007]

However, generally, the dust collection efficiency in the electrostatic precipitator is proportional to the strength of the electric field (electric field density), and the dust collection efficiency increases as the particle size of the dust increases at the same electric field density. In the conventional electrostatic precipitator 8 described above, the discharge electrode 5
Since the mutual distance between the dust collecting member 6 and the dust collecting member 6 is set to be uniform, the electric field densities between the respective discharge electrodes 5 and the dust collecting member 6 are the same, and the collecting gas is collected upstream in the flowing direction of the processing gas 1. Most of the dust, which contains a large amount of dust with a large particle size, is unevenly collected, while a small amount of dust with a small particle size cannot be collected and remains on the downstream side. There was a problem that the discharge electrode 5 and the dust collecting member 6 had to be additionally installed on the downstream side because of a small amount of dust having a small particle size that could not be exhausted.

When it is attempted to increase the electric field density in order to quickly collect dust having a small particle size, the applied voltage may be increased to increase the electric field density of discharge. There is a limit to increase it,
There is a problem in that it is necessary to newly install a power supply device having a large capacity to switch the power supply device, or to cause a problem that power consumption is significantly increased.

Further, it is conceivable that the electric field density is increased by uniformly setting the mutual distance between the discharge electrode 5 and the dust collecting member 6, but on the upstream side, the particle size, which is easy to collect dust, is large. There is a problem in that electric energy loss increases because dust is charged more than is necessary.

The present invention has been made in view of the above circumstances, and an electric precipitator capable of efficiently collecting dust by applying electric fields of different strengths to the dust in the processing gas without changing the voltage. Is intended to provide.

[0011]

SUMMARY OF THE INVENTION The present invention is directed to a casing for guiding a treated gas containing dust, a discharge electrode disposed in the casing in a direction intersecting the flow direction of the treated gas, and a treated gas. An electrostatic precipitator comprising a dust collecting member arranged in parallel with the discharge electrode having a transparent structure of
The present invention relates to an electrostatic precipitator in which the discharge electrode and the dust collecting member are arranged such that the mutual distance between the discharge electrode and the dust collecting member is gradually narrowed in the flow direction of the processing gas.

Further, a plurality of hoppers, which are divided in the flow direction of the processing gas, may be formed in the lower portion of the casing.

[0013]

Therefore, in the present invention, when the electrostatic precipitator is operated by applying, for example, the same voltage between the respective discharge electrodes and the dust collecting member, the discharge electrodes on the upstream side in the flowing direction of the processing gas and the dust collecting members are collected. Since a relatively large mutual distance is set between the dust member and the dust member, the electric field density is lowered and a relatively weak electric field is formed. Then, dust with a large particle size that is easily collected is collected from the processing gas.

Furthermore, the electric field density is increased as the mutual distance between the discharge electrode and the dust collecting member is gradually narrowed in the flow direction of the processing gas, and an electric field stronger than the electric field on the upstream side is formed on the downstream side. The dust having a small particle size is gradually collected from the treated gas as it goes downstream. However, the voltage can be adjusted by increasing or decreasing as necessary on the upstream side or the downstream side.

If a plurality of hoppers divided in the flow direction of the processing gas are formed in the lower part of the casing and the collected dust is blown off and collected in each hopper, the dust is collected according to the particle size. It becomes possible.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 show an embodiment of the present invention, in which a gas inflow duct 2 for guiding a treated gas 1 containing dust is provided on one side and the treated gas 1 after dust collection is discharged. At the bottom of the casing 4 equipped with the gas discharge duct 3 on the other side,
A plurality of (three in the illustrated example) hoppers 9, 10, 11 that are divided in the flow direction of the processing gas 1 are formed.

Directly above the inlet hopper 9 inside the casing 4, a discharge electrode 5 and a dust collecting member 6 oriented so as to intersect with the flow direction of the processing gas 1 are separated by a relatively large distance x. They are alternately suspended and supported, and the discharge electrode 5 and the dust collecting member 6 form a coarse powder recovery block 12.

At a position directly above the intermediate hopper 10 inside the casing 4, the discharge electrode 5 and the dust collecting member 6 oriented so as to intersect with the flow direction of the processing gas 1 in the same manner as described above are provided with the mutual distance x. They are suspended and supported alternately with a smaller mutual interval y, and the discharge electrode 5 and the dust collecting member 6 form a medium powder recovery block 13.

Further, at a position directly above the outlet hopper 11 inside the casing 4, a discharge electrode 5 and a dust collecting member 6 oriented so as to intersect the flow direction of the processing gas 1 in the same manner as described above are disposed at the mutual intervals. They are suspended and supported at a mutual distance z smaller than y, and a fine powder collecting block 14 is formed by the discharge electrode 5 and the dust collecting member 6.

The discharge electrode 5 of any of the coarse powder recovery block 12, the intermediate powder recovery block 13 and the fine powder recovery block 14 described above.
2 is also suspended and supported as shown in FIG. 2, and the suspension member 17 is suspended via the insulating material 16 from the discharge electrode support beam 15 installed in the upper part of the casing 4 in the width direction (left and right direction in FIG. 2). Is attached, and the discharge electrodes 5 are suspended and supported by the suspending members 17. Each discharge electrode 5 has a structure in which a discrete wire 5b is arranged in a frame 5a.

Further, all the dust collecting members 6 are suspended and supported as shown in FIG. 3, and the dust collecting member supporting beam is erected in the width direction (left and right direction in FIG. 3) in the upper part of the casing 4. 18, a mesh-like dust collecting member 6 is hung and supported in parallel with the discharge electrode 5 via a suspending member 19, and each dust collecting member 6 is arranged so as to sandwich the discharge electrode 5. Has become.

Reference numeral 20 in the figure vibrates the discharge electrode 5 and the dust collecting member 6 through a hammer rod 21 by a crank mechanism or a hammer driven by a motor provided outside the casing 4. And a hammering device for removing dust adhering to the dust collecting member 6, and 22 for insulating the hammering rod 21 of the hammering device 20 provided corresponding to the discharge electrode 5 and the penetrating portion of the casing 4. Is an insulating material provided on the.

FIG. 4 is a front view showing an example of the hammering device 20 described above. The hammering rod 21 fixed to the discharge electrode 5 and the dust collecting member 6 slides the casing 4 tightly and slidingly. It penetrates as much as possible and projects out of the casing 4. A collar portion 23 is integrally formed at the tip of the hammering rod 21, and between the collar portion 23 and the outer surface of the casing 4,
A spring 24 is provided. Because of this, hammer 2
1 is biased by a spring 24 in a direction projecting from the casing 4, and the collar portion 23 is pressed against a hammering cam 25.

The hammering cam 25 is fixed to the rotary shaft 26. When the hammering cam 25 rotates clockwise together with the rotary shaft 26, the collar portion 23 of the hammering cam 25 is rotated.
The diameter of the portion abutting against is gradually increased, and the collar portion 23, the hammer rod 21, the discharge electrode 5 or the dust collecting member 6 is integrally moved toward the inside of the casing 4 against the force of the spring 24. I will let you.

As the hammer striking cam 25 continues to rotate in the clockwise direction, the diameter of the portion of the hammer striking cam 25 that abuts the collar portion 23 suddenly becomes smaller, and the collar portion 23, the hammer striking rod 21,
The discharge electrode 5 or the dust collecting member 6 rapidly moves in the direction of protruding from the casing 4 by the force of the spring 24.
As the hammering cam 25 continues to rotate, the discharge electrode 5
Alternatively, the dust collecting member 6 will be vibrated left and right. 27
Is a cover.

When the same voltage is applied between the discharge electrode 5 and the dust collecting member 6 in each of the blocks 12, 13 and 14 to operate the electrostatic precipitator, the coarse powder collecting block 12 Since the relatively large mutual distance x is provided between the discharge electrode 5 and the dust collecting member 6, the electric field density is lowered and a relatively weak electric field is formed. In the case of, only coarse powder having a large particle size that is easily collected is collected from the processing gas 1.

Further, since the discharge electrode 5 and the dust collecting member 6 in the intermediate powder recovery block 13 are separated by a mutual interval y smaller than the mutual interval x, the electric field density is increased and the coarse powder recovery block 12 is described. An electric field stronger than the electric field of 1 is formed, and only the intermediate powder that is easily collected from the processing gas 1 after the coarse powder is collected in the coarse powder recovery block 12 is collected.

Further, the discharge electrode 5 and the dust collecting member 6 in the fine powder collecting block 14 are separated from each other by a mutual distance z smaller than the mutual distance y, so that the electric field density is increased and the intermediate powder collecting block 13 is An electric field stronger than the electric field of 1 is formed, and fine powder having a small particle size remaining in the processing gas 1 after the intermediate powder is collected in the intermediate powder recovery block 13 is collected. .

The dust collected in each of the blocks 12, 13 and 14 falls by its own weight or is blown off by the hammer striking rod 21 of the hammer striking device 20 and the hoppers 9, 10 and 1 are discharged.
1 is collected respectively.

Therefore, according to the above embodiment, the coarse powder recovery block 12, the intermediate powder recovery block 13, and the fine powder recovery block 1 are used.
By setting the mutual intervals x, y, and z to be narrower in the order of 4, it is possible to apply electric fields of different strengths to the dust in the processing gas 1 without changing the voltage, so that the dust can be collected according to the particle size. However, it is possible to solve the problem that the discharge electrode 5 and the dust collecting member 6 have to be additionally installed on the downstream side due to a small amount of dust having a small particle diameter that is difficult to collect as in the conventional case, and thus the minimum required amount can be solved. Dust can be efficiently collected by the discharge electrode 5 and the dust collecting member 6, and since unnecessary dust is not unnecessarily charged to dust with a large particle size that is easy to collect, electrical energy loss is also minimized. Can be suppressed.

Further, the dust in the processing gas 1 is coarse powder, medium powder,
Each hopper 9, 10, 11 is collected as fine powder by particle size.
Since it can be collected in a small amount, it can be used for the purpose of classifying dust in the processing gas 1.

The electrostatic precipitator of the present invention is not limited to the above-mentioned embodiment, and the discharge electrode and the dust-collecting member arranged in the casing are not necessarily separated by block as in the illustrated embodiment. It is not necessary to set the interval narrowly, and it is also possible to set the individual discharge electrodes and the dust collecting members so that the mutual intervals are continuously narrowed. Furthermore, the discharge electrodes and the dust collecting members do not necessarily have to be arranged alternately. Alternatively, for example, one set of one discharge electrode sandwiched by two dust collecting members before and after may be set as one set, and a plurality of sets may be connected, and a load may be applied between the discharge electrode and the dust collecting member. The voltage to be applied can be adjusted by increasing / decreasing it appropriately at any position in the flow direction of the processing gas, and if it is used only for collecting dust, one hopper at the bottom of the casing can be used. Can be summarized in That the discharge electrode may have a shape other than the discrete wire, the dust collecting member may have a shape other than the mesh, and other various changes may be made without departing from the scope of the present invention. Of course.

[0034]

According to the above-mentioned electrostatic precipitator of the present invention, various excellent effects as described below can be obtained.

(I) By arranging the discharge electrode and the dust collecting member so that the mutual distance between the discharge electrode and the dust collecting member is gradually narrowed in the flow direction of the processing gas, the dust in the treatment gas can be maintained without changing the voltage. Since it is possible to apply an electric field of different strength to collect dust according to the particle size, it is possible to efficiently collect dust with the minimum required discharge electrode and dust collecting member, and the particle size is easy to collect. It is possible to prevent unnecessary electric charges from being applied to large dust particles, and to minimize electric energy loss.

(II) If a plurality of hoppers that are divided in the flow direction of the processing gas are formed in the lower portion of the casing, the dust in the processing gas can be collected according to particle size and collected in each hopper. Therefore, the electrostatic precipitator can be used for the purpose of classifying the dust in the processing gas.

[Brief description of drawings]

FIG. 1 is a cut side view showing an embodiment of the present invention.

FIG. 2 is a view taken along the line II-II of FIG.

FIG. 3 is a view on arrow III-III in FIG. 1.

FIG. 4 is a front view showing an example of the hammering device of FIGS. 2 and 3.

FIG. 5 is a cut plan view showing an example of a conventional electrostatic precipitator.

FIG. 6 is a cut plan view showing another example of a conventional electrostatic precipitator.

[Explanation of symbols]

 1 Processing Gas 4 Casing 5 Discharge Electrode 6 Dust Collection Member 9 Input Side Hopper 10 Intermediate Hopper 11 Output Side Hopper x Mutual Interval y Mutual Interval z Mutual Interval

Claims (2)

[Claims] 1. A casing for guiding a treated gas containing dust, a discharge electrode arranged in the casing in a direction intersecting a flow direction of the treated gas, and a permeable structure for the treated gas. An electrostatic precipitator comprising a discharge electrode and a dust collecting member arranged in parallel, wherein the discharge electrode and the dust collecting member are arranged such that the mutual distance between the discharge electrode and the dust collecting member is gradually narrowed in the flow direction of the processing gas. An electrostatic precipitator characterized by arranging. 2. The electrostatic precipitator according to claim 1, wherein a plurality of hoppers, which are divided in the flow direction of the processing gas, are formed in the lower portion of the casing.