JP3823666B2 - Moving electrode type electrostatic precipitator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a moving electrode type electrostatic precipitator, and in particular, includes a large number of discharge frames suspended within a casing at a predetermined interval, and a large number of moving electrodes that circulate every other discharge frame. The present invention relates to a moving electrode type electrostatic precipitator.
[0002]
[Prior art]
This type of moving electrode type electrostatic precipitator is known as an electric precipitator for removing dust in, for example, boiler exhaust gas from a thermal power plant and exhaust gas from various furnaces for iron making. The schematic structure will be described with reference to FIGS.
[0003]
In FIG. 6, the moving electrode type electrostatic precipitator 10 includes a casing 12, a hopper 13 below the casing 12, a number of discharge frames 14 and a number of moving electrodes 15 disposed in the casing 12. The exhaust gas 17 introduced into the casing 12 from the inlet flue 16 is removed by the principle of electrostatic dust collection and discharged from the outlet flue 18. The collected dust falls into the hopper 13 and is taken out from the discharge port 20 by a mechanism (not shown).
[0004]
FIG. 7 is a view taken along the line AA of FIG. 6, and a large number of discharge frames 14 are provided in the casing 12 at predetermined intervals via suspension frames 24 suspended from the insulator 22 shown in FIG. It is suspended. In addition, a large number of moving electrodes 15 that circulate every other discharge frame 14 are provided.
[0005]
FIG. 8 is a perspective view showing the structure of the moving electrode 15, and a pair of endless chains 30, 30 are stretched between the upper drive wheel 26 and the lower roller 28, and the pair of endless chains 30, A plurality of dust collecting electrode plates 32 are suspended by 30 at the position of the intermediate portion 33 in the width direction, and a loop is formed as a whole. The shaft 34 of the drive wheel 26 is rotated by a drive mechanism (not shown), and the rotation of the shaft 34 is transmitted to a pair of endless chains 30 and 30 meshing with the drive wheel 26 to form a plurality of dust collecting electrode plates forming the loop. 32 moves around the discharge frame 14 every other turn.
[0006]
FIG. 9 is a layout view of the lower part of the moving electrode 15, and the dust collecting electrode plate 32 suspended and lowered by the endless chain 30 makes a U-turn at the position of the lower roller 28 and starts to rise. A pair of rotating brushes 36 and 38 (hereinafter, the pair of rotating brushes are collectively referred to as brush means and denoted by reference numeral 40) at a position sandwiching the dust collecting electrode plate 32 immediately after the ascent is provided for each lane of the moving electrode 15. Is arranged. The brushes 36 and 38 are made by implanting a metal brush on the rotating shaft, and the brush 36 is rotated clockwise and the brush 38 is counterclockwise so that dust adhering to the surface of the dust collecting electrode plate 32 is wiped down. Rotate around. The dust collecting electrode plate 32 from which the dust adhered to the surface has been removed by the brush means 40 is sequentially raised, and the dust in the exhaust gas is collected on the surface by the principle of electric dust collection in the discharge region from the discharge frame 14, It will descend again.
[0007]
[Problems to be solved by the invention]
When the moving electrode 15 is a relatively large device, the number of the moving electrodes 15 is 50 to 100 lanes, and the same number of driving devices for driving these moving electrodes 15 are required. There was a problem that the installation cost became large.
[0008]
In order to improve the above problems, it is conceivable that a plurality of adjacent moving electrodes can be driven by a common drive mechanism, thereby reducing the installation cost of the drive mechanism. However, in this type of moving electrode type electrostatic precipitator, the moving electrode is driven under harsh conditions for handling the dust, and therefore, the sliding portions at various places are severely worn by the attached dust. In addition, there are many opportunities for various members to be corroded and worn by corrosive exhaust gas and spark discharge based on high voltage charge. For this reason, if one moving electrode cannot be driven due to abrasion due to dust or the like, the entire driving mechanism must be stopped, and the drive of the remaining normal moving electrodes is sacrificed.
[0009]
The object of the present invention is to improve the problems of the prior art, without stopping the common drive mechanism even when some of the adjacent moving electrodes cannot be driven, It is an object of the present invention to provide a moving electrode type electrostatic precipitator capable of continuously driving the remaining normal moving electrodes.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the present invention loops as a whole by a large number of discharge frames suspended at predetermined intervals in a casing and a plurality of dust collecting electrode plates suspended by a pair of endless chains. In the moving electrode type electrostatic precipitator in which the dust collecting plate includes a plurality of moving electrodes that circulate every other discharge frame, and drives a plurality of adjacent moving electrodes by a common drive mechanism, An arbitrary moving electrode can be separated from driving by the common driving mechanism.
[0011]
That is , according to the present invention, the drive mechanism transmits a driving force to an adjacent moving electrode by chain transmission, and when any moving electrode is separated from driving by the common driving mechanism, the driving mechanism is provided on the driving shaft of the moving electrode. Further, the chain transmission sprocket is idled.
[0012]
Further, the present invention is characterized in that dust collecting plates of a plurality of adjacent moving electrodes driven by the common driving mechanism move with a phase difference from each other.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a perspective view showing a driving mechanism of a moving electrode according to an embodiment of the present invention. The overall configuration of the moving electrode type electrostatic precipitator is the same as that described in the section of the prior art, and the same reference numerals as those described above mean the same elements.
[0014]
In FIG. 1, moving electrodes 15A, 15B, 15C and 15D are arranged in parallel. In each moving electrode, the dust collecting electrode plate (not shown) is suspended at the endless chain 30 and makes a U-turn at the positions of the drive wheels 26A, 26B, 26C, and 26D, and turns from rising to lowering. Drive shafts 34A, 34B, 34C, and 34D of each drive wheel are pivotally supported at a casing position (not shown), one end projects out of the casing, and driving sprockets 42A, 42B, 42C, and 42D are provided at the ends. Is provided.
[0015]
As shown in FIG. 2, these driving sprockets 42 have a structure in which an inner sprocket wheel 44 and an outer sprocket wheel 46 are integrated, and a collar 48 and a presser flange 50 are formed at the end of the driving shaft 34. It is placed between them. Usually, the outer sprocket wheel 46 and the presser flange 50 are used by fastening them with presser bolts 52. The presser flange 50 is integrated with the drive shaft 34 by a key 54. For this reason, the sprocket 42 and the drive shaft 34 rotate integrally through the presser flange 50. On the other hand, when the presser bolt 52 is removed and the outer sprocket wheel 46 and the presser flange 50 are separated, the sprocket 42 is idled with respect to the drive shaft 34 via the oilless metal 56.
[0016]
A common drive source 58 is disposed outside the casing, and the rotational force of the drive source 58 is transmitted to the sprockets 42B and 42C via the sprocket 60 and the chain 62. As a result, the drive shafts 34B and 34C integral with the sprockets 42B and 42C rotate, and the movable electrodes 15B and 15C are driven. Further, the rotation of the sprocket 42B is transmitted to the sprocket 42A through the chain 64, and the moving electrode 15A is driven by the rotation of the drive shaft 34A integrated with the sprocket 42A. Similarly, the rotation of the sprocket 42A is transmitted to the sprocket of an adjacent moving electrode (not shown) via the chain 66, and the adjacent moving electrode is driven. The moving electrode 15D and a moving electrode (not shown) adjacent to the moving electrode 15D are also driven by the same chain transmission as described above.
[0017]
As a result, a plurality of adjacent moving electrodes 15 can be driven by the common drive source 58. In the present embodiment, the driving source 58 is arranged in the center, and the moving electrode 15 of 6 lanes in total, 3 lanes on each side, is driven by this common driving source 58. By applying the same structure to other moving electrodes, in the moving electrode type electrostatic precipitator with 60 moving electrodes, all the moving electrodes can be driven by 10 drive sources, This greatly contributes to simplification of the driving device.
[0018]
On the other hand, in the case where a plurality of adjacent moving electrodes are driven by a common driving source, when one moving electrode cannot be driven, a situation occurs in which the entire driving mechanism must be stopped. In this embodiment, when any of the plurality of moving electrodes cannot be driven, it can be dealt with by separating the moving electrode from driving by a common driving mechanism. That is, the chain transmission sprocket 42 is idled with respect to the drive shaft 34 of the moving electrode 15. Specifically, as shown in FIG. 2, the presser bolt 52 that fastens the sprocket 42 and the presser flange 50 is removed. By removing the presser bolt 52, the sprocket 42 and the presser flange 50 are separated, and the drive shaft 34 does not rotate even if the sprocket 42 rotates. For this reason, while rotating all of the plurality of sprockets 42 provided in the common drive mechanism, the rotation shaft 34 of any movable electrode that cannot be driven can be separated from the common drive mechanism.
[0019]
Therefore, when one of the moving electrodes cannot be driven due to an unexpected situation, the remaining normal moving electrodes can be continuously driven by separating the moving electrode from the common driving mechanism as described above. For this reason, for example, when operating a mobile electrode type electrostatic precipitator for exhaust gas treatment of a thermal power plant, even if one of the 60 lanes of the mobile electrode becomes inoperable, the mobile electrode type precipitator of the mobile electrode type It is possible to avoid a situation in which the whole, and thus the whole thermal power plant, is stopped. The movable electrode that cannot be driven may be restored at the occasion of regular or temporary repair of the thermal power plant.
[0020]
In the present embodiment, in addition to the above features, the dust collecting electrode plates of the plurality of adjacent moving electrodes are driven with a phase difference from the dust collecting electrode plates of the other moving electrodes. That is, with reference to the phase of the dust collecting electrode plate 32A of the moving electrode 15A in FIG. 3, the dust collecting electrode plate 32B of the moving electrode 15B is driven with a phase difference delayed by 30 °, and the dust collecting electrode of the moving electrode 15C is driven. The pole plate 32C is driven with a phase difference delayed by 60 °. Hereinafter, similarly, the dust collecting electrode plate 32 of the moving lane 15 of 6 lanes driven by the common drive source 62 is arranged at intervals of 30 ° in the order of 0 °, 30 °, 60 °, 90 °, 120 °, 150 °. Driven with phase difference.
[0021]
The reason why a phase difference is provided for driving the dust collecting electrode plate 32 as described above is closely related to the outer shape of the dust collecting electrode plate 32. That is, as shown in FIG. 4, the dust collecting plate 32 has a structure in which the periphery of a thin steel plate 72 is reinforced mainly by a relatively thick vertical frame 74 and horizontal frame 76 from the viewpoint of weight reduction and strength. It is said.
[0022]
For this reason, when the dust collecting electrode plate 32 passes between a pair of brushes 36 and 38 arranged at fixed positions as shown in FIG. 5, the brush brush 78 of the thin steel plate 72 shown in FIG. Is relatively small, and the pressing force of the brush against the steel plate 72 is small, so that the passage resistance when the steel plate 72 passes through the brush means 40 is small. On the other hand, in the portion of the horizontal frame 76 shown in (b), the brush brush 78 is greatly deformed and the pressing force of the brush against the horizontal frame 76 is large, so that the passage resistance when the horizontal frame 76 passes through the brush means 40 is increased. Becomes larger. In one trial calculation example, the passage resistance when the horizontal frame 76 passes through the brush means 40 is about three times that of the steel plate 72.
[0023]
Therefore, if the plurality of moving electrodes 15 are driven by the common drive source 58 in a state where the dust collecting electrode plates 32 of the plurality of adjacent moving electrodes 15 as shown in FIG. The horizontal frames 76 of the plurality of dust collecting electrode plates 32 pass through the brush means 40 at the same time, and the load on the common drive source and transmission mechanism at this time increases. For this reason, it is necessary to install a common drive source and transmission mechanism so as to withstand a temporary large load, resulting in an increase in equipment cost.
[0024]
On the other hand, in the present embodiment, as shown in FIG. 3, the dust collecting electrode plates 32 of the plurality of adjacent moving electrodes 15 have a phase difference from each other. Therefore, when the plurality of moving electrodes 15 are driven by a common drive source, the horizontal frames 76 of the plurality of dust collecting electrode plates 32 are less likely to pass through the brush means 40 at the same time, and the common drive source and transmission mechanism are reduced. The load on is averaged. For this reason, the capacity | capacitance and intensity | strength of a common drive source and a transmission mechanism can be made small, and installation cost can be reduced.
[0025]
【The invention's effect】
According to the moving electrode type electrostatic precipitator according to the present invention, even when some of the adjacent moving electrodes driven by the common driving mechanism cannot be driven, the common driving mechanism The remaining normal moving electrodes can be continuously driven without stopping the operation.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a driving mechanism of a moving electrode according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing an end structure of a drive shaft of a moving electrode according to an embodiment of the present invention.
FIG. 3 is a layout view of a lower part of a moving electrode according to an embodiment of the present invention.
FIG. 4 is a perspective view showing a structure of a dust collecting electrode according to an embodiment of the present invention.
FIG. 5 is an explanatory view showing an operating state of the brush means according to the embodiment of the present invention.
FIG. 6 is a side sectional view showing a general configuration of a moving electrode type electrostatic precipitator.
7 is an AA arrow view of FIG. 6;
FIG. 8 is a perspective view showing a general structure of a moving electrode.
FIG. 9 is a layout diagram of a general lower part of a moving electrode.
[Explanation of symbols]
12 ... Casing 14 ... Discharge frame 15 ... Moving electrode 26 ... Drive wheel 30 ... Endless chain 32 ... Dust collecting plate 34 ... Drive shaft 42 ... Sprocket 52 ... Presser bolt 58 ... Drive source

Claims (2)

A loop is formed as a whole by a large number of discharge frames suspended within a casing at a predetermined interval and a plurality of dust collecting electrode plates suspended by a pair of endless chains, and the dust collecting electrode plates In a moving electrode type electrostatic precipitator equipped with a large number of moving electrodes that circulate every other frame and drives a plurality of adjacent moving electrodes by a common driving mechanism, the driving mechanism is driven to the adjacent moving electrodes by chain transmission It is intended to transmit force, and when separating any moving electrode from driving by the common driving mechanism, the chain transmission sprocket provided on the driving shaft of the moving electrode is idled. Moving electrode type electrostatic precipitator.   The moving electrode type electrostatic precipitator according to claim 1, wherein the dust collecting plates of the plurality of adjacent moving electrodes move with a phase difference.

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