JP2003010733A - Plates for flat type dust collectors - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a means for improving the dust collecting capability of a large flat type electric dust collector, thereby improving the dust collecting efficiency without enlarging or adding an electric dust collector. The above object is achieved by assembling a dust collecting electrode for a flat electric dust collector having a plurality of electrode plates connected in the width direction, wherein an insert piece is inserted between the plurality of electrode plates. . At this time, the insert piece is preferably a member having an H-shaped or I-shaped cross section.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic precipitator used in equipment such as a steel factory where a large amount of dust is generated, and more particularly to an electrode plate for a precipitator used in a large flat type electrostatic precipitator.

[0002]

2. Description of the Related Art An electrostatic precipitator is a device that charges dust particles through a gas containing dust in an electric field to which a high voltage is applied, and electrically charges the charged dust particles onto a dust collecting electrode surface by Coulomb force. is there. An outline of the structure of this electrostatic precipitator is shown in FIGS. 3 and 4. In this type of electrostatic precipitator, the dust-containing gas is introduced from the inlet duct 1 into the electrostatic precipitator body 7, and in the electrostatic precipitator body 7 the discharge electrode 3 and the dust collecting electrode 5 are shown in FIG. As such, they are installed alternately so as to be parallel to the gas flow direction. A high voltage is applied to the discharge electrode 3 from a DC power source 4, and the dust collecting electrode is grounded. Regarding the polarity, the discharge electrode is generally the negative electrode and the dust collecting electrode is the positive electrode.

Therefore, the dust particles in the dust-containing gas introduced into the main body 7 of the electrostatic precipitator are negatively charged and are attracted to the surface of the dust collecting electrode, which is the positive electrode, by the Coulomb force, and are deposited on the surface of the dust collecting electrode to remove dust. To be done. The dust particles accumulated on the surface of the dust collecting electrode are separated from the dust collecting electrode by a hammering device or a cleaning device (not shown), and discharged from the lower hopper 6 to the outside. Also,
The gas from which the dust has been removed is diffused into the atmosphere through an outlet duct 2 by an unillustrated blower or the like, or is guided to a separate exhaust gas treatment facility.

The overall structure of the electrostatic precipitator is as described above. However, in the electrostatic precipitator used for equipment having a large amount of dust-containing gas to be treated, such as iron-making equipment, the area of the dust-collecting electrode should be large. Therefore, the dust collecting electrode is not made into a single unitary body, but is composed of a plurality of electrode plates 5a, 5b, etc. divided in the width direction as shown in FIG. The beam 8b is combined to form an assembled dust collecting electrode to reduce the manufacturing cost. Such a dust collector is used, for example, in a building dust collector of a steel factory in a steel mill or a dust collector generated around a scarf machine of a continuous cast slab.

[0005]

However, the dust collection efficiency in such a large flat plate type electrostatic precipitator is
It is lower than the value theoretically predicted from the dust content, dust particle size, voltage, dimensions of each part of the dust collector, and the like. Therefore, for example, when an attempt is made to increase the dust collecting capacity in response to an environmental problem, the dust collecting machine is inevitably increased in size or added although the theoretical dust collecting capacity of the dust collector still has a margin. The present invention provides a means for improving the dust collecting efficiency of such a large-sized flat plate type electrostatic precipitator, thereby improving the dust collecting efficiency without enlarging or increasing the size of the electric precipitator.

[0006]

According to the present invention, there is provided an assembled dust collecting electrode for a flat plate electrostatic precipitator in which a plurality of electrode plates are connected in a width direction, and an insert piece is inserted between the plurality of electrode plates. By achieving the above, the above object is achieved.
At that time, the insert piece is preferably a member having an H-shaped or I-shaped cross section.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

For the flat plate type electrostatic precipitator, for example, "Factory operation series No. 19 augmented dust collection" issued by Kagaku Kogyo Co., Ltd.
As described in (Issue 1st supplement issued in October 1983), the large flat plate electrostatic precipitator to which the present invention is applied has a flat plate dust collecting electrode of the type shown in FIGS. In the used electrostatic precipitator, as shown in FIG. 5, the dust collecting electrode is divided in the width direction and is constituted by a plurality of electrode plates 5a, 5b, etc., and these are joined by the upper end beam 8a and the lower end beam 8b to assemble the dust collector. It has an electrode.

The inventors of the present invention have sought a cause that the dust collection efficiency of such a large flat plate type electrostatic precipitator is lower than the theoretically predicted value, and the cause is the interelectrode gap due to the deflection or deflection of the dust collection electrode. It was found that there was a change in distance. That is, the dust collecting electrode of the flat plate type electrostatic precipitator is long in the vertical direction, and therefore, it is bent at the middle portion in the height direction of the dust collecting electrode or shakes due to the force of the gas flow during operation, which causes the dust collecting electrode and the dust collecting electrode to collect. The distance between the dust electrodes becomes indefinite, charge failure occurs, and the dust collection ability lower than the theoretically predicted value can be exhibited.

The occurrence of such bending and deflection of the dust collecting electrode plate is caused by insufficient rigidity of the dust collecting electrode plate. Therefore, if the rigidity of the collecting electrode plate is increased and the bending and the deflection are reduced, the dust collecting ability can be improved in the dust collecting device of the above type.

From this point of view, the present invention provides an insert piece 9 as shown in FIG. 1 in the gap between the plurality of electrode plates 5a, 5b constituting the assembled dust collecting electrode, and the assembled dust collecting electrode 9 is mounted on the insert piece 9. It has a function of imparting rigidity in the height direction. The insert piece may be of any material and shape as long as it has such a rigidity imparting function, but it is preferable that the insert piece has an H-shaped or I-shaped cross-sectional shape as shown in FIG. It is preferable to use steel as the material in terms of strength and price.

[0012]

[Example] The present invention was applied to a dust collector for a scarf machine of a continuous cast slab in an iron factory. This dust collector has a capacity
It is a flat plate type electrostatic precipitator having 1400 m ³ and 104 assembled dust collecting electrodes.

The assembled dust collecting electrode is an electrode plate 2 having a width of 1 m and a height of 5.8 m.
It is composed by connecting the upper and lower beams with each other and integrating them, and the connecting portion has a cross section as shown in FIG.
The insert piece 9 having an H shape was arranged, the electrode plate was sandwiched and fixed by the opening, and rigidity was imparted to the assembled dust collecting electrode.

As a result, the dust collection efficiency was 94.1% before using the insert piece, but the use of the insert piece improved the dust collection efficiency to 97.1%. The dust collection efficiency is calculated by the following formula. Dust collection efficiency = (Dust content of dust collector inlet side gas-Dust collector outlet side gas dust content) / Dust collector inlet side gas dust content The scarf machine of the continuous casting slab was obtained by continuous casting. It is a facility to ablate and remove defective parts on the surface of steel slabs by flames, and a large amount of iron oxide fumes are generated by the flames.

[0015]

As described above, according to the present invention, since the insert piece having high rigidity is used when the plurality of electrode plates of the assembled dust collecting electrode of the electric dust collector are connected in the width direction, the dust collecting process is performed. The dust collecting electrode plate does not bend or shake. As a result, the capacity of the dust collector can be greatly improved, which contributes to stable operation of dust collection work. It also contributes to the reduction of equipment costs required for environmental measures.

[Brief description of drawings]

FIG. 1 is a front view of an assembled dust collecting electrode of the present invention.

FIG. 2 is a sectional view taken along line AA of the assembled dust collecting electrode of the present invention.

FIG. 3 is a partially cutaway front view showing a schematic configuration of an electric dust collector.

FIG. 4 is a partially cutaway plan view showing a schematic configuration of an electric dust collector.

FIG. 5 is a front view showing a configuration of a conventional assembled dust collecting electrode.

[Explanation of symbols]

1: Entrance side duct 2: Outlet duct 3: Discharge electrode 4: DC power supply 5: Assembly dust collection electrode 5a, 5b: Electrode 6: Lower hopper 7: Electric dust collector body 8a: Top beam 8b: Bottom beam 9: Insert piece

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koichi Hayashi             1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Made in Kawasaki             Chiba Steel Works, Ltd. F-term (reference) 4D054 AA08 BA01 BA06 BC03 BC04                       BC21 BC34 BC40

Claims (2)

[Claims] 1. A flat plate type electrostatic precipitator in which an insert piece is inserted between the plurality of polar plates in an assembled dust collecting electrode for a flat plate electrostatic precipitator formed by connecting a plurality of polar plates in a width direction. Electrode plate. 2. The electrode plate for a flat type electrostatic precipitator according to claim 1, wherein the insert piece is a member having an H-shaped or I-shaped cross section.