JPH07265737A - Electric precipitator - Google Patents

Abstract

PURPOSE:To eliminate the possibility of the lowering of dust collection efficiency even when the flow velocity of air to be treated is relatively high. CONSTITUTION:An electric precipitator 9 is connected to a flow duct 1 of air to be treated and a dust collection. electrode 11 and a discharge electrode 12 are arranged in a casing 10. The dust collection electrode 11 is formed of a support frame 13 and a large number of the lattice plates 14, 14,... attached to the support frame 13. Each of the lattice plates 14 is composed of a curved plate-shaped one and fixed to the support frame 13 so that the surface 14a thereof opposed to the flow of the air to be treated becomes a curved surface recessed along the width direction thereof.

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 particles by being installed in a flow path of a gas to be treated in which particles such as dust are mixed.

[0002]

2. Description of the Related Art Generally, in an electrostatic precipitator, a high voltage is applied between a discharge electrode and a dust collecting electrode to cause corona discharge between the discharge electrode and the dust collecting electrode, so that a strong electric field is generated. This is a configuration in which a portion of the air is ionized to generate a charge band. Then, for example, when the electrostatic precipitator is installed in the flow path of the gas to be treated in which particles such as dust are mixed and the gas to be treated is introduced into the electrostatic precipitator, when the gas to be treated reaches the charge zone, Particles such as dust are electrically charged, and the charged particles are attached to and collected by a dust collecting electrode having an opposite potential.

FIG. 4 is a view showing an example of a conventional general electrostatic precipitator. An electrostatic precipitator 2 is connected to a flow duct 1 for a gas to be treated which extends in a horizontal direction, and an electrostatic precipitator 2 is provided. The fan 3 is connected in the subsequent stage. This electric dust collector 2
Is provided with a large number of lattice plates 4, 4, ... Arranged so that the length direction extends in the vertical direction (direction perpendicular to the paper surface) and the width direction is parallel to the flow direction of the gas to be treated. The dust collecting electrode 6 is configured to allow the gas to be processed to pass through the gaps 5, 5, ... Between the lattice plates 4, 4, ..., And the discharge extending parallel to the flow direction and having both ends formed in a needle shape. The structure is such that the discharge electrodes 8 having the rods 7 are alternately arranged along the flow direction (only one set of the dust collecting electrodes 6 and the discharge electrodes 8 is shown in FIG. 4).

[0004]

However, in the conventional electrostatic precipitator 2 described above, since the width direction of the grid plate 4 of the dust collecting electrode 6 is parallel to the flow direction, the gas to be treated is a grid. .. flow forward through the gaps 5, 5, ... Between the lattice plates 4, 4, .. Therefore, particularly when the flow velocity of the gas to be treated is relatively high, particles such as dust may pass through the charge band formed between the discharge electrode 8 and the dust collection electrode 6, and the dust collection efficiency may be increased. There was a problem that it would decrease.

The present invention has been made in order to solve the above problems, and provides an electrostatic precipitator in which the dust collection efficiency does not decrease even when the flow velocity of the gas to be treated is relatively high. With the goal.

[0006]

In order to achieve the above object, the electrostatic precipitator of the present invention is provided with a large number of grid plates whose length direction extends perpendicularly to the flow direction of the gas to be treated. An electrostatic precipitator comprising: a dust-collecting electrode that allows the gas to be processed to pass through the gaps between the grid plates; and a discharge electrode that is opposed to and is separated from the dust-collecting electrode by a predetermined distance. The lattice plate has a plate shape curved in the width direction, and is arranged such that the surface facing the flow of the gas to be treated is a curved surface that is concave along the width direction. It is a thing.

Further, the lattice plate may be formed in a flat plate shape and arranged so that its width direction is oblique to the flow direction of the gas to be treated.

[0008]

In the electrostatic precipitator of the present invention, the surface of the lattice plate facing the flow of the gas to be treated is formed into a curved surface which is concave along the width direction thereof. Compared to the case where the lattice plate is installed parallel to the flow direction as in the dust device, the area facing the flow of the gas to be treated becomes larger. When the gas to be processed passes through the gap between the grid plates of the dust collecting electrodes, particles such as dust collide with the curved surface, lose momentum, and fall downward. Therefore, even when the flow velocity of the gas to be processed is relatively high,
The particles are electrically collected by the dust collecting electrode by being charged, and in addition, the particles are mechanically separated from the gas to be treated by colliding with the dust collecting electrode. The same is true when the lattice plate has a flat plate shape and is arranged so that its width direction is oblique with respect to the flow direction of the gas to be treated. It is mechanically separated from the process gas.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a view showing an electrostatic precipitator 9 of the present embodiment, in which reference numeral 1 is a flow duct for a gas to be treated,
Reference numeral 10 is a casing, 11 is a dust collecting electrode, and 12 is a discharge electrode.

The electrostatic precipitator 9 is connected in the middle of the flow duct 1 for the gas to be treated, and has a structure in which a plurality of dust collecting electrodes 11 and a plurality of discharge electrodes 12 are alternately arranged in the casing 10. (In FIG. 1, one set of dust collecting electrode 11 and discharge electrode 1
2 only). Then, the fan 3 is installed in the subsequent stage of the electrostatic precipitator 9, so that the gas to be processed flows from the left to the right in the figure (direction of arrow A).

As shown in FIG. 2, the dust collecting electrode 11 is composed of a support frame 13 and a large number of grid plates 14, 14, ... Attached to the support frame 13 and extending in the vertical direction. The gap 1 between these lattice plates 14, 14, ...
The gas to be processed passes through 5, 15, .... Then, as shown in FIG. 1, the entire dust collecting electrode 11 is attached to the casing 10 so as to be perpendicular to the flow direction of the gas to be treated.

Further, each lattice plate 14 is a plate shape curved in the width direction, and has a surface 14a facing the flow of the gas to be treated.
Is fixed to the support frame 13 so as to form a curved surface that is concave along the width direction.

On the other hand, as shown in FIG.
A plurality of supporting members 17, 17 fixed to the supporting frame 16 in the vertical direction, and discharge rods 18 attached to each supporting member 17 at regular intervals in the vertical direction and extending in the horizontal direction,
18, the tip of the discharge rod 18 is formed in a needle shape in order to enhance the discharge strength, and the tip is arranged so as to face the dust collecting electrode 11.

Further, as shown in FIG. 1, a high voltage applying device 19 for applying a high voltage is provided between the discharge electrode 12 and the dust collecting electrode 11.

When using the electrostatic precipitator 9 having the above-mentioned structure, the high voltage applying device 19 is used to discharge the electrode 12 and the dust collecting electrode 11.
When a high voltage is applied between and, a high-strength corona discharge is generated from the tip of the discharge rod 18 toward the dust collecting electrode 11, and a charge band is formed. Therefore, when the fan 3 is operated to introduce the gas to be treated in which particles such as dust are mixed into the electrostatic precipitator 9, the particles such as dust are electrically charged when the gas to be treated reaches the charge zone, Dust collecting electrode 11 with charged particles of opposite potential
It adheres to and is collected.

In the electrostatic precipitator 9 of this embodiment, since the lattice plate 14 has a curved surface which is concave on the surface 14a side facing the flow of the gas to be treated, it is different from the conventional electrostatic precipitator. Compared with the case where the lattice plate is installed parallel to the flow direction, the contact area with the gas to be treated becomes larger. Then, the gas to be treated is the lattice plates 14 and 1 of the dust collecting electrode 11.
When passing through the gaps 15, 15, ..., Particles such as dust collide with the curved surface 14a, lose momentum, and fall downward. Therefore, even if the flow velocity of the gas to be treated is relatively high, the particles are charged and electrically collected by the dust collecting electrode 11, and a part of the particles collide with the dust collecting electrode 11. Are mechanically separated from the gas to be treated. That is, it is possible to improve the efficiency of collecting particles as a whole, as compared with the conventional device that collects particles only electrically.

In the electrostatic precipitator 9 of the present embodiment, the grid plate 14 of the dust collecting electrode 11 is curved in the width direction, but instead of this structure, as shown in FIG. 3 (b). To
It is also possible to make the lattice plate 20 into a flat plate shape and arrange it so that its width direction is oblique to the flow direction of the gas to be treated (the direction of arrow A in the figure). In this case as well, it is similar to the lattice plate 14 of the present embodiment shown in FIG. 3A, and particles such as dust collide with the lattice plate 20 and lose momentum, and fall downward. Therefore, the particles are not only electrically collected by the dust collecting electrode 21, but also mechanically collected, so that the particle collecting efficiency as a whole can be improved.

In the above embodiment, the grid plate 1
In the case where the plates 4 and 20 have a curved plate shape, both in the case of a flat plate, the lattice plates 14 and 20 are assumed to extend in the vertical direction. However, instead of this configuration, the lattice plates are extended in the horizontal direction or the diagonal direction. It may be present. On the other hand, the shape of the discharge electrode 12 is not limited to this embodiment, and various shapes can be used.

[0019]

As described above in detail, in the electrostatic precipitator of the present invention, the surface of the lattice plate facing the flow of the gas to be treated has a curved surface which is concave along the width direction. As a result, when the gas to be processed passes through the gap of the grid plate of the dust collecting electrode, particles such as dust collide with the curved surface, lose momentum, and fall downward. Therefore, even when the flow velocity of the gas to be treated is relatively high, the particles are mechanically separated from the gas to be treated by colliding partly with the dust collecting electrode in addition to being electrically collected by the dust collecting electrode. Since it is separated into particles, it is possible to improve the efficiency of collecting particles as a whole, as compared with a conventional device that attempts to collect particles only electrically.
The same is true when the lattice plate is a flat plate and the width direction of the lattice plate is oblique to the flow direction of the gas to be treated. The efficiency of collecting particles can be improved.

[Brief description of drawings]

FIG. 1 is a plan sectional view showing an electrostatic precipitator according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a dust collecting electrode and a discharge electrode of the same device.

FIG. 3 is a plan sectional view showing another embodiment of the lattice plate of the same device.

FIG. 4 is a diagram showing an example of a conventional electrostatic precipitator.

[Explanation of symbols]

 9 Electrostatic Precipitator 11 Dust Collection Electrode 12 Discharge Electrode 14, 20 Lattice Plate 14a Face Faced to Flow of Processed Gas 15 Gap between Lattice Plates

Claims (2)

[Claims] 1. A dust collecting electrode having a plurality of lattice plates, the length direction of which extends perpendicularly to the flow direction of the gas to be treated, and the gas to be treated passing through the gaps between the lattice plates, In an electrostatic precipitator including a discharge electrode that is opposed to a dust collection electrode by a predetermined distance, the lattice plate has a plate shape curved in the width direction, and the flow of the gas to be treated is An electrostatic precipitator characterized by being arranged such that a surface facing the surface is a curved surface that is concave along the width direction. 2. A dust collecting electrode having a plurality of lattice plates, the length direction of which extends perpendicularly to the flow direction of the gas to be treated, and the gas to be treated passing through the gaps between the lattice plates, In an electrostatic precipitator including a discharge electrode that is arranged to face a dust collecting electrode and is separated from the dust collecting electrode by a predetermined distance, the lattice plate has a flat plate shape, and a width direction thereof is a flow direction of the gas to be treated. An electrostatic precipitator characterized by being arranged obliquely with respect to.