JP3384095B2 - Electric dust collector - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is installed in a flow path of a gas to be treated having a high dust content, such as a cement production facility, and collects dust and the like. The present invention relates to an electric precipitator suitable for the above. 2. Description of the Related Art Generally, an electrostatic precipitator generates a corona discharge between both a discharge electrode and a dust collection electrode by applying a high voltage between the discharge electrode and the dust collection electrode. This is a configuration in which a charged band is generated by ionizing air in a portion having a strong electric field. Then, for example, when the electric dust collector 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 electric dust collector, when the gas to be treated reaches the charged band, Then, particles such as dust are charged, and the charged particles adhere to and collect on the dust collecting electrode having the opposite potential. FIG. 4 is a view showing an example of a conventional general electric precipitator, in which an electric precipitator 2 is connected to a flow duct 1 for a gas to be treated extending in a horizontal direction. The fan 9 is connected to the subsequent stage. This electric dust collector 2
Are provided with a number of holes 3, 3,.
Are formed alternately in the casing 7 along the flow direction of the gas to be treated (the direction indicated by the arrow X in the figure) and the discharge electrodes 6 having the discharge rods 5 having needle-shaped ends. (Only one set of the collection electrode 4 and the discharge electrode 6 is shown in FIG. 4). In front of these dust collection electrodes and discharge electrodes 4 and 6, a large number of holes 10 extend in a direction perpendicular to the flow of the gas to be treated.
A plurality of dispersion plates 8, 10,... Therefore, the gas to be treated introduced into the apparatus 2 flows forward in a state where the flow is expanded by the plurality of dispersion plates 8, 8,.
The particles such as dust are charged when they reach the charge band formed between the particles, and the charged particles adhere to the dust collecting electrode 4 and are collected. That is, the dispersion plate 8 is for improving the collection efficiency of the particles by expanding the flow of the gas to be treated and dispersing the particles in a direction orthogonal to the flow. [0004] However, particularly when the dust content of the gas to be treated is high, such as when the above-mentioned conventional electric precipitator 2 is installed in a cement manufacturing facility or the like. Since the flow of the gas to be treated is expanded by providing the dispersion plate 8 in front of the discharge electrode 6 and the collection electrode 4, the collection efficiency is still insufficient, and the collection efficiency is further increased. It has been desired to provide an electric precipitator that can perform the operation. The present invention has been made in view of the above circumstances, and provides an electric precipitator capable of maintaining high collection efficiency even when the gas to be treated has a high dust content. The purpose is to: [0006] In order to achieve the above object, an electric precipitator according to the present invention is provided in a flow path through which a gas to be treated flows, and is mounted on a casing and the casing. An apparatus main body including a dust collecting electrode and a discharge electrode, and a dispersion plate that is connected to the apparatus main body on the upstream side in the flow direction of the gas to be treated and expands the flow of the gas to be treated. is composed of a preliminary chamber, a plurality provided the dispersion plate along the direction of flow, adjacent therein 2
One of the two dispersion plates is a preliminary discharge electrode, the other is a preliminary dust collection electrode, and a high voltage generator for applying a high voltage is connected between the preliminary discharge electrode and the preliminary dust collection electrode. It is a feature. The electric dust collecting apparatus of the present invention is characterized in that the gas to be treated is subjected to preliminary dust collection before being introduced into the apparatus main body in the preliminary chamber. That is, a plurality of dispersion plates provided in the spare chamber constitute a preliminary discharge electrode and a spare dust collecting electrode, and the high voltage generating device is connected therebetween, so that the spare chamber further forms another electric dust collecting device. Make up. Therefore, when the gas to be treated having a high dust content is introduced into the electrostatic precipitator, the dispersion plate in the preliminary chamber not only functions to expand the flow of the gas to be treated, but also has a certain degree of collection in the initial stage. The dust content is reduced by dusting, that is, after the preliminary dust collection, the gas to be treated is introduced into the apparatus main body, where the dust is collected in earnest. An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a view showing an electric precipitator 11 of the present embodiment. In the drawing, reference numeral 1 denotes a flow duct for a gas to be treated, 12 denotes an apparatus main body, 13 denotes a spare room, and 9 denotes a fan. An electric precipitator 11 composed of an apparatus main body 12 and a spare chamber 13 is connected in the middle of the flow duct 1 for the gas to be treated. A fan 9 is provided at a stage subsequent to the electrostatic precipitator 11, and the operation of the fan 9 causes the gas to be treated to be introduced from the distribution duct 1 to the spare chamber 13 of the electric precipitator 11 and the apparatus main body 12 in this order. It has become so. The preliminary chamber 13 includes a plurality of dispersion plates 15 extending in a direction perpendicular to the flow direction of the gas to be treated in a casing 14.
a, 15b,... are provided. Then, as shown in FIG. 2, these dispersion plates 15a, 15b,
Are formed with a large number of circular holes 16a, 16b,. FIG.
, The dispersion plate 15a located at the most upstream side is a preliminary dust collection electrode 17a, and every other dispersion plate 15c, 15e is a preliminary dust collection electrode 17c. 17e. Then, these preliminary dust collecting electrodes 17a, 17
As shown in FIG. 2, the remaining dispersion plates 15 b and 15 d sandwiched between c and 17 e have a needle-like shape with a sharp tip between adjacent holes 16 b and 16 b in the vertical, horizontal and oblique directions. Are attached, and these dispersion plates 15b, 15d are used as preliminary discharge electrodes 19b, 19d. In addition, these preliminary dust collecting electrodes 17a, 17c, 17e
A high-voltage applying device 29 for applying a high voltage is connected between the pre-discharge electrodes 19b and 19d. The voltage consumed by the high voltage application device 29 is determined by the
2 may be smaller than the consumption voltage of the high voltage application device 30. The apparatus main body 12 has a configuration in which a plurality of dust collection electrodes 20 and a plurality of discharge electrodes 21 are alternately arranged in a casing 14 (FIG. 1 shows a set of the collection electrodes 20 and discharge electrodes 21). 2
1 only). The casing 14 is set so that the apparatus body 12 has a larger cross-sectional area in the flow direction of the gas to be treated than the preliminary chamber 13. In addition, each dust collection electrode 2
Numeral 0 is constituted by a plate having a large number of holes 22, 22,..., And the gas to be processed passes through the large number of holes 22, 22,. The dust collecting electrode 20 is attached to the casing 14 so as to be perpendicular to the flow direction of the gas to be treated. On the other hand, the discharge electrode 21 includes a plurality of support members 23, 23,
, And horizontally extending discharge rods 24, 24,... Attached to each support member 23 at regular intervals in the vertical direction. The tip of the discharge rod 24 is shaped like a needle to increase discharge intensity. The dust collecting electrode 20 is formed so as to face the dust collecting electrode 20. And a high voltage applying device 3 for applying a high voltage between the discharge electrode 21 and the dust collecting electrode 20.
0 is provided. In the electric precipitator 11 having the above structure, when a high voltage is applied between the discharge electrode 21 and the precipitating electrode 20 by the high voltage applying device 30 of the main body 12, the precipitating end of the discharge rod 24 is used. Corona discharge occurs toward 20 and a charged band is formed. Then, when the gas to be treated is introduced into the apparatus main body 12, particles such as dust are charged when the gas to be treated reaches the charged band, and the charged particles adhere to the dust collecting electrode 20 of the opposite potential and are trapped. Gathered. The same applies when a high voltage is applied between the preliminary discharge electrodes 19b and 19d and the preliminary dust collection electrodes 17a, 17c and 17e by the high voltage application device 29 in the preliminary chamber 13. Corona discharge is generated between the pre-collection electrodes 17a, 17c and 17e to generate a charge band, and the particles are charged, thereby causing the pre-collection electrodes 17a, 17c and 17e to be charged.
a, 17c, and 17e. However, the spare room 13
Since the voltage consumption of the high voltage application device 29 is set smaller than that of the device main body 12, the corona discharge in the preliminary chamber 13 is smaller in intensity than the corona discharge in the device main body 12, and the collection rate of particles is also lower. Low. Therefore, the electric precipitator 11 of the present embodiment.
In the above, the dispersion plates 15a, 1
5b,... Not only increase the flow of the gas to be treated,
Preliminary discharge electrodes 19b and 19d, preliminary dust collection electrodes 17a and 17
By configuring c and 17e, when the gas to be treated having a high dust content is introduced into the preliminary chamber 13, light dust collection in the initial stage, that is, so-called preliminary dust collection is performed. Then, the gas to be treated is introduced into the apparatus main body 12 in a state where the flow of the gas is expanded and the degree of dust content is reduced, where full-scale dust collection is performed. That is, in the apparatus 11 of the present embodiment, the preliminary chamber 13 is provided with two functions of the preliminary dust collection and the improvement of the efficiency of the main dust collection by expanding the flow. The collection efficiency of the particles can be improved as compared with the apparatus. In this embodiment, the preliminary discharge electrode 1
7a, 17c, and 17e, the discharge rod 18 is provided on the perforated plate.
, 18b,..., but the present invention is not limited to this configuration. As shown in FIG. 3, the relatively thick grid plate 2 extends in the vertical and horizontal directions with respect to the rectangular support frame 25.
6 may be fixed, and a discharge rod 27 may be mounted between the intersections of the grids on the grid plate 26 and the adjacent intersections. Even if the preliminary discharge electrode 28 is configured in this manner, it is possible to provide both functions such as preliminary dust collection and flow expansion. In the above embodiment, the spare chamber 13 of the casing 14 has a rectangular parallelepiped shape. Instead of this shape, the cross-sectional area gradually increases from the flow duct 1 side toward the apparatus main body 12 side. It is also possible to provide a plurality of dispersion plates having a gradually increasing size along the flow direction of the gas to be treated in a quadrangular pyramid shape (indicated by a two-dot chain line in FIG. 1). On the other hand, as for the shape and configuration of the dust collecting electrode 20 and the discharge electrode 21 of the apparatus main body 12, for example, a grid plate of the dust collecting electrode 20 is installed in a horizontal direction or an oblique direction, and the dust collecting electrode 21 is formed of a perforated plate. However, the present invention is not limited to the present embodiment, and can have various shapes and configurations. As described above in detail, in the electric dust collecting apparatus of the present invention, a preliminary discharge electrode and a preliminary dust collecting electrode are constituted by a plurality of dispersing plates provided in the preliminary chamber, and a preliminary discharging electrode and a preliminary dust collecting electrode are provided between these. Is connected to a high voltage generator, so that the spare chamber constitutes one electric precipitator. Therefore, the dispersion plate installed in the preliminary chamber not only has a function of expanding the flow of the gas to be treated conventionally, but also has a function of performing preliminary dust collection. The flow is expanded and the dust content is reduced and introduced into the apparatus main body, where full-scale dust collection is performed. That is, in the electric precipitator of the present invention, the preparatory chamber is provided with two functions of preparatory precipitating and improving the efficiency of the main precipitating by expanding the flow. The efficiency of collecting particles can be improved as compared with the apparatus, and the apparatus is suitable for use in a cement manufacturing facility or the like in which a gas to be treated having a high dust content is generated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan sectional view showing an electric precipitator according to one embodiment of the present invention. FIG. 2 is an enlarged perspective view of a preliminary dust collecting electrode and a preliminary discharge electrode of the apparatus. FIG. 3 is a perspective view showing another embodiment of the preliminary dust collection electrode and the preliminary discharge electrode. FIG. 4 is a plan sectional view showing an example of a conventional electric dust collector. [Description of Signs] 11 Electric dust collector 12 Device main body 13 Spare chamber 14 Casing 15a, 15b, 15c, 15d, 15e Dispersion plates 17a, 17c, 17e Spare dust collecting electrodes 19b, 19d Spare discharge electrode 20 Collecting electrode 21 Discharge Electrode 29 High voltage generator (in spare room)

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Nobuyuki Abe 3-2-16-1 Toyosu, Koto-ku, Tokyo Ishikawa-jima-Harima Heavy Industries, Ltd. Toyosu Sogo Office (56) References JP-A-60-227846 (JP, A) JP-A-60-166051 (JP, A) JP-A-54-69479 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B03C 3/00-3/88

Claims (1)

(57) [Claims 1] Installed in a flow path through which a gas to be treated flows,
An apparatus main body including a casing and a dust collecting electrode and a discharge electrode attached to the casing, and a device main body connected to the apparatus main body on the upstream side in the flow direction of the gas to be treated, to enlarge the flow of the gas to be treated; And a spare chamber provided with a dispersing plate for causing the dispersing plate to be provided. A plurality of dispersing plates are provided along the flow direction, and one of two adjacent dispersing plates is a preliminary discharge electrode and the other is a preliminary collecting electrode. An electric dust collector, wherein the dust collector is a dust collector, and a high voltage generator for applying a high voltage is connected between the preliminary discharge electrode and the spare dust collector.