JPH0427454A - Electrostatic precipitator - Google Patents

Abstract

PURPOSE:To treat the gas contg. the dust of high concn. and mist by alternately disposing discharge plate units and dust collecting plate unit. CONSTITUTION:The dust collecting plate units 11 are disposed at the forefront stage at the rear end stage, and between them the discharge plate units 23 and the dust collecting plate units 11 are alternately disposed. The dust collecting plate units 11 and the discharge plate units 23 disposed as mentioned above are received in a housing 1. A coarse dust collecting filter 35 and a coagurated mist collecting filter 36 are disposed respectively in front of the dust collecting plate unit 11 of forefront stage and in the rear of the dust collecting plate unit 11 of rear end. The gas contg. dust flows along the surfaces of dust collecting plates 15 and the discharge plates 27. When the gas contg. dust passes through the corona discharge generated between the end part of the surface of a dust collecting plate 15 and the end part of the surface of a discharge plate 27, the dust or the mist in the gas is electrically charged.

Description

[Detailed description of the invention] [Industrial application field] This invention relates to an electrostatic precipitator.

The electrostatic precipitator of the present invention is used to collect dust from various types of furnaces, wheelers, cleaning equipment, and other equipment that generate dust or mist.

[Prior Art] Electrostatic condensation devices are broadly classified into one-stage type and two-stage type depending on the charging type, and many types of devices have been developed and are in use.

A single-stage electrostatic concentrator consists of a discharge electrode, an insulated and supported wire, a barbed electrode rod, an edged plate, etc., and a collection electrode consists of a cylinder, a flat plate, etc. A high negative voltage is applied to the discharge electrode to generate corona discharge and charge the fine particles in the scum. The charged particles are attracted to the collection rod by Coulomb force and deposited there.

The two-stage electrostatic precipitator includes a charging section consisting of a pair of opposing cathode rods and a discharge wire disposed between them, and a collection section consisting of a group of positive and negative parallel plates. A high positive voltage is applied to the discharge wire to generate a corona discharge between it and the cathode rod, thereby charging the particles. The charged fine particles are attracted to and adhere to the collection plate to which a negative high voltage is applied among the parallel plates.

[Problems to be Solved by the Invention] Since the single-stage electrostatic concentrator has a large distance between poles, the device becomes large and requires a high-voltage power source. Therefore, the equipment is expensive and maintenance is not easy.

Two-stage electrostatic precipitators require a low inter-electrode voltage and a small inter-electrode distance due to structural constraints and the use of positive corona discharge. As a result, spark discharge is likely to occur due to the accumulation of dust and mist on the dust collecting electrode.

Therefore, the reality is that the two-stage electrostatic precipitator is limited to processing gases with low dust or mist concentrations.

In addition, because the discharge wires are thin, they tend to break easily, which poses maintenance problems.

Therefore, the present invention aims to provide an electrostatic precipitator that can process gas containing high concentrations of dust and mist, is easy to maintain, and is small and inexpensive.

[Means for Solving the Problem] The electrostatic precipitator of the present invention includes a plurality of dust collecting plate units in which a plurality of elongated dust collecting plates are arranged so that the plate surfaces are parallel to each other, and a plurality of elongated dust collecting plates. The discharge electrode plate unit includes a plurality of discharge electrode plate units in which the electrode plates are arranged so that the plate surfaces are parallel to each other. The dust collector plate units and the discharge electrode plate units are alternately arranged at intervals in the direction along the plate surface.

The collector plate is made of ordinary steel plate or stainless steel plate with a thickness of about 0.5 to 5 mm. Depending on the capacity of the dust collecting device, the length of the dust collecting plate is, for example, about 0.3 to 2 m, and the width is about 20 to 50 mm. The collector plate is not limited to a flat plate, but may be a bent or curved plate. A large number of such dust collection plates (10 to 5
(approximately 0) are arranged at intervals of, for example, 30 to 60111[+1]. Further, the arranged dust collecting plates are held by a rectangular frame or the like to form a collecting plate unit.

The discharge electrode plate is also made of ordinary steel plate or stainless steel plate with a thickness of about 0.5 to 1 mm, and has the same length and width as the dust collector plate. Further, the tip of the discharge electrode plate facing the collector plate is tapered to be thin and sharp. The discharge electrode plate is 1~
They are arranged at intervals corresponding to the four dust collection plates. The discharge electrode plate is held by a rectangular frame or the like to form a discharge electrode plate unit.

In the dust collector plate unit and the discharge electrode plate unit configured as described above, the frontmost stage and the last stage are the dust collector plate units, and the discharge electrode plate units and the dust collector plate units are arranged alternately between them. Placed. The distance between the collector plate unit and the discharge electrode plate unit is 30 to 12
It is about 0 mm.

The number of collector plate units and discharge electrode plate units is 3 to 3.
It is about the number of people.

In addition, the positive electrode is connected to the dust collector plate unit, and the negative electrode is connected to the discharge electrode plate unit, and a voltage of 3 to 8 kV is applied between the two.
An electric field of about /cm is formed.

[Operation] The gas containing gas flows along the dust collector plate surface and the discharge electrode plate surface. When the phosphor-containing gas passes through a corona discharge generated between the end of the dust collector plate surface and the end of the discharge electrode plate surface, the dust or mist in the phosphor-containing gas becomes electrically charged. The charged dust or mist is attracted to the dust collecting plate by Coulomb force and adheres to it.

Since the porosity-containing gas passes through a plurality of stages of dust collecting plate units and discharge electrode plate units, the porosity-containing gas is collected multiple times. Further, since the gas containing gas flows along the dust collector plate surface and the discharge electrode plate surface, the pressure loss of the waste flow is low even if a plurality of dust collector plate units and discharge electrode plate units are arranged in stages.

[Example] FIG. 1 shows an example of an electrostatic condenser of the present invention.

As shown in the drawings, the electric discharge device mainly includes a housing 1, a high-voltage current #8, a dust collector plate unit +1, and a discharge electrode plate unit 23.

As shown in FIGS. 2 and 3, the collection board unit 11 has a large number of collection boards 15 arranged with their surfaces parallel to each other and fixed to a square frame 12. That is, a spacer 18 is inserted between adjacent collector plates 15. The rod 20 passes through the hole 16 of the dust collection plate 15 and the spacer 18, and the rod 20
Both ends of are supported by vertical members 13 of a rectangular frame 12, respectively. In this embodiment, one dust collection plate unit 11 includes 34 dust collection plates 15, and the dust collection plates 15 are made of ordinary steel plates with a thickness of 1.0 mm. The height of the dust collection plate 15 is 450mm, and the width is 25n+m.
It is. In addition, the interval between adjacent dust collecting plates 15 is 15
It is mm.

The discharge electrode plate unit 23 has the same structure as the above-mentioned dust collector plate unit, as shown in FIGS. 4 and 5.

That is, spacers 31 are provided between adjacent discharge electrode plates 27.
is inserted. A rod 33 passes through the hole 28 of the discharge electrode plate 27 and the spacer 31, and both ends of the rod 33 are supported by the vertical member 25 of the rectangular frame 24, respectively. As shown in FIG. 6, the distal end portion 29 of each discharge electrode plate 27 facing the dust collector plate 15 is tapered to be narrow and sharp.

In this embodiment, one discharge electrode plate unit 23 includes 17 discharge electrode plates 27, and the discharge electrode plates 27 have a thickness of 0.
Made of 5mm stainless steel plate. Discharge electrode plate 27
The height is 450 mm and the width is 38 mm. Further, the interval between adjacent discharge electrode plates 27 is 30 mm.

The dust collector plate unit 11 and the discharge electrode plate unit 23 configured as described above have the dust collector plate unit 11 disposed at the frontmost stage and the last stage, and the discharge electrode plate unit 11 is arranged between the dust collector plate unit 11 and the discharge electrode plate unit 23 as shown in FIGS. The plate units 23 and the dust collecting plate units 11 are arranged so as to be alternately lined up. The collector plate unit 11 and discharge electrode plate unit 23 arranged in this manner are housed in the house sink 1. In this embodiment, the number of stages of the dust collecting plate unit 11 is three, and the number of stages of the discharge electrode plate unit 23 is four. The distance between the dust collecting plate unit and the discharge electrode plate unit 23 is 30 m.
It is m. A filter 35 for collecting coarse dust is disposed in front of the dust collecting plate unit 1 at the first stage, and a filter 36 for collecting aggregated mist is arranged after the dust collecting plate unit 110 at the last stage.

A high-pressure support frame 3 is attached to the top of the housing 1 via insulators 4. Further, the discharge electrode plate unit 23 is connected to the high voltage support frame 3 by a power supply rod 6. The negative electrode of the high voltage DC power supply 8 is connected to the discharge electrode plate unit 23, and the housing 1 is grounded. A DC high voltage of 15 kV is applied between the two.

The scum goes from the left side to the right side in Figure 1,
It flows along the collector plate 15 surface and the discharge electrode plate 27 surface.

When the scum passes through the corona discharge generated between the end of the dust collecting plate 15 surface and the end of the discharge electrode plate 27 surface,
Dust or mist in the gas containing gas becomes electrically charged. The charged dust or mist is attracted to the collection plate 15 by Coulomb force. Then, as shown in FIG. 7, it adheres to the circumferential surface of the end portion (upstream side and downstream side) of the fruit plate 15.

When the amount of dust adhering reaches a certain amount, the operation of the dust collector is stopped and the dust is removed from the dust collector plate 15.

This invention is not limited to the above embodiments. For example, the dust collecting plate may have a bent shape like the dust collecting plate 37 shown in FIG. 8, or it may have a curved shape like the dust collecting plate 39 shown in FIG. 9. The dust collecting plates 37 and 39 each have a wide surface facing the flow of the gas containing gas, thereby improving the dust collecting performance. Further, the dust collecting plate 41 shown in FIG. 10 is placed on a circular arc 42 such that its tip is located equidistant from the tip of the discharge electrode plate 27. Spark discharge occurs from the gap between the poles with the smallest distance, but by varnishing equidistantly as described above, spark discharge does not occur in a particular gap before others.

[Effects of the Invention] In this invention, the dust collecting plate units and the discharge electrode plate units are alternately arranged in multiple stages to collect dust multiple times. Therefore, compared to a -stage electrostatic concentrator, the distance between the collector plate unit and the discharge electrode plate unit can be made smaller, the voltage applied between them can be lowered, and the use of a low-voltage power supply is possible. It is possible.

Furthermore, since negative corona discharge is used, the spark voltage is high.

Therefore, even if the inter-electrode voltage is increased and the inter-electrode distance is increased compared to a two-stage electrostatic precipitator, the performance will not deteriorate at all. Therefore, spark discharge due to the accumulation of dust and mist on the electrode plate is difficult to occur, and it is possible to treat scum containing highly concentrated dust and mist.

Since the collector plate and discharge electrode plate are long and thin,
Even if these units are arranged in multiple stages, the entire device can be made smaller. Due to the miniaturization of the device and the use of the low voltage power supply described above, the device is inexpensive.

Furthermore, since the device is compact and the discharge electrode is plate-shaped rather than a thin wire that is prone to breakage, it will not break even during long-term use and maintenance is easy.

Note that, since the gas containing gas flows along the dust collector plate surface and the discharge electrode plate surface, the pressure loss of the gas flow is low even if there are multiple stages of the dust collector plate unit and the discharge electrode plate unit.

[Brief explanation of drawings]

Fig. 1 shows an embodiment of the present invention, and Fig. 2 is a side view of an electrostatic precipitator, Fig. 2 is a front view showing an example of the dust collecting plate unit of the electrostatic precipitator shown in Fig. 1, and Fig. 3 is a side view of an electrostatic precipitator. is m in Figure 2
4 is a front view showing an example of a discharge electrode plate unit, FIG. 5 is a sectional view taken along line V to V in FIG. 4, and FIG. 6 is a sectional view of the discharge electrode plate unit shown in FIG. FIG. 7 is an enlarged plan view of the electrode plate, FIG. 7 is a plan view showing the arrangement of the dust collector plate unit and discharge electrode plate unit, and FIGS. 8, 9, and 10 are plan views showing other examples of the dust collector plate, respectively. It is a diagram. 1... Housing, 3... High pressure support frame, 4...
... Insulator, 6... Power supply rod, 8... High voltage DC power supply,
11... Dust collection plate unit, 12... Frame, 1
5... Dust collection plate, 18... Spacer, 20... Rod, 23... Discharge electrode plate unit, 24... Frame, 27-... Discharge electrode plate, 31... Spacer, 33・
...Rod, 37, 39, 41--Dust collection plate.

Claims (1)

[Claims] 1. A plurality of dust collecting plate units in which a plurality of elongated dust collecting plates are arranged so that their plate surfaces are parallel to each other, and a plurality of plurality in which a plurality of elongated discharge electrode plates are arranged so that their plate surfaces are parallel to each other. 1. An electrostatic precipitator comprising: a discharge electrode plate unit, wherein the dust collector plate unit and the discharge electrode plate unit are alternately arranged at intervals in a direction along the plate surface.