JP7300298B2 - Charging device and dust collector - Google Patents

Description

The present invention relates to charging devices and dust collectors.

A high-voltage side output terminal of a high-voltage power supply for corona discharge is connected to a terminal portion of the corona discharge electrode via a conductor and a porcelain tube, and a ground side output terminal is connected to and grounded via a conductor to the counter electrode. The electrodes are plate-shaped electrodes arranged parallel to the gas flow and parallel to each other. Together with the ceiling plate and the bottom plate, they form a gas duct with a rectangular cross section. It is vertically insulated along the center axis, and is fixedly supported by the porcelain pipe that penetrates the ceiling plate at the top and the insulator provided on the bottom plate at the bottom, respectively. A corona discharge unit is known in which a wire mesh protector is grounded together with a group of counter electrodes and also serves as an auxiliary counter electrode (for example, Patent Document 1).

JP-A-8-112549

Here, in the case of adopting a configuration in which the discharge electrode is arranged upstream of the processing airflow from the most upstream end of the processing airflow of the ground electrode, the ground electrode treats the ions generated and diffused by the discharge electrode. Since the particles cannot be drawn in the direction intersecting the airflow, it is not possible to secure a large space for charging the suspended fine particles contained in the processing airflow.

Further, when adopting a configuration in which a flat plate-shaped ground electrode is arranged in a direction along the processing airflow as the ground electrode that attracts the ions generated and diffused by the discharge electrode, it is necessary to secure a wide space for the ions to diffuse. It is not possible to make a compact device for charging suspended particles contained in the processing air stream.

An object of the present invention is to reduce suspended particulates contained in a processing airflow as compared to a configuration in which a discharge electrode is arranged upstream of the processing airflow from the most upstream end of the processing airflow of a ground electrode. To secure a wide space for electrification.

Another object of the present invention is to provide a ground electrode for attracting ions generated and diffused by the discharge electrode, which is arranged in the direction along the processing gas flow. To make a device for charging floating fine particles contained in an air stream compact.

Based on this object, the present invention provides a discharge electrode formed of a plurality of fibrous conductors for generating and diffusing ions by discharge, and a discharge electrode maintained at ground potential to attract the ions generated and diffused by the discharge electrode. and a ground electrode for ion-charging suspended fine particles contained in the treatment gas stream, the discharge electrode being disposed between the ground electrodes in the treatment gas stream, and at least all or all of the plurality of fibrous conductors of the discharge electrode. A portion of the charging device is located downstream of the process airflow from the most upstream end of the ground electrode.

Here, the discharge electrode is arranged in the center between two adjacent ground electrodes, and is arranged so that the separation distance to the ground electrode in the direction perpendicular to the processing airflow is 20 mm or more and 100 mm or less. can be

Also, the ground electrode may be formed of a flat plate-like conductive member. In that case, the ground electrode may be arranged so as to face the discharge electrode at a specific position in the direction orthogonal to the process airflow.

In addition, the present invention includes a discharge electrode formed of a plurality of fibrous conductors for generating and diffusing ions by discharge, and a discharge electrode maintained at a ground potential, attracting the ions generated and diffused by the discharge electrode, and Also provided is a charging device provided with a ground electrode for charging floating fine particles contained in the discharge electrode with ions, wherein the ground electrode is arranged at a position to draw the ions generated and diffused by the discharge electrode in a direction intersecting the processing air flow.

Furthermore, the present invention includes a discharge electrode that is formed of a plurality of fibrous conductors and that generates and diffuses ions by discharge, and a discharge electrode that is maintained at a ground potential and attracts the ions generated and diffused by the discharge electrode into the process gas stream. and a ground electrode for electrifying the suspended fine particles contained in the airflow with ions. The ground electrode includes a flat plate-shaped first electrode portion arranged in a direction along the processing airflow, and a flat plate-shaped first electrode portion arranged in a direction intersecting the processing airflow. A charging device is also provided including a second electrode portion having a shape.

Here, the ground electrode is arranged between the tip portion of the first electrode portion on the upstream side of the processing air flow and the central portion of the second electrode portion so that the first electrode portion and the second electrode portion are substantially perpendicular to each other. and may be formed by connecting the . In that case, the ground electrode has a length of 0.4 ≦ L2/L1≦2.

Further, the discharge electrode may be disposed downstream of the processing airflow relative to the most upstream end of the processing airflow of the ground electrode.

Also, the discharge electrode may be arranged in the center between two adjacent ground electrodes so that the distance to either ground electrode is 20 mm or more and 100 mm or less.

Also, the plurality of fibrous conductors may be carbon fibers.

Furthermore, the charging device may further include a high voltage power source that applies a high voltage between the discharge electrode and the ground electrode. In that case, the high-voltage power supply may apply a positive or negative DC high voltage between the discharge electrode and the ground electrode, or apply a positive or negative DC high voltage between the discharge electrode and the ground electrode. A pulse type or alternating type high voltage of polarity or negative polarity may be applied, or a high voltage opposite to the high voltage normally applied at a predetermined interval between the discharge electrode and the ground electrode. It may be one that applies a high voltage of polarity.

Furthermore, the present invention also provides a dust collector comprising any one of the charging devices described above and a dust collecting section that collects dust by adhering airborne fine particles charged by the charging device.

Here, the dust collection part may be configured by a dust collection filter, or may be configured by a heat exchanger.

According to the present invention, compared to the case where the discharge electrode is arranged upstream of the processing airflow from the end of the ground electrode on the most upstream side of the processing airflow, suspended particles contained in the processing airflow are reduced. It becomes possible to secure a large space for electrification.

In addition, according to the present invention, as compared with the case where a flat plate-shaped ground electrode is arranged in the direction along the processing airflow as the grounding electrode that attracts the ions generated and diffused by the discharge electrode, It is possible to make the device for charging the suspended fine particles contained in the compact.

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows the whole electric dust collector structure in the 1st Embodiment of this invention. FIG. 4 is a perspective view showing the flow of ions when discharge is generated by the discharge electrode in the first embodiment of the present invention; FIG. 4 is a top view showing the flow of ions when a discharge is generated by the discharge electrode in the first embodiment of the present invention; 8A is a perspective view showing the structure of a charging unit of Example 1, and FIG. 7B is a perspective view showing the structure of a charging unit of Comparative example 1. FIG. 5 is a graph showing the difference in ion diffusion direction between the charging portion of Example 1 and the charging portion of Comparative Example 1. FIG. 5 is a graph showing the difference in performance with respect to ozone concentration for obtaining dust collection performance between the charging portion of Example 1 and the charging portion of Comparative Example 1. FIG. 8A is a perspective view showing the structure of a charging unit of Example 1, and FIG. 7B is a perspective view showing the structure of a charging unit of Comparative example 2. FIG. 5 is a graph showing the difference in performance regarding discharge voltage for obtaining dust collection performance between the charging portion of Example 1 and the charging portion of Comparative Example 2. FIG. 5 is a graph showing the relationship between the discharge gap, the dust collection performance, and the ozone generation performance in the charging section of Example 1. FIG. 4 is a graph showing the relationship between discharge gap and spark resistance. 8A is a perspective view showing the configuration of a charging unit of Example 1, and FIG. 7B is a perspective view showing the configuration of a charging unit of Comparative Example 3. FIG. 5 is a graph showing the difference in performance with respect to discharge voltage for obtaining dust collection performance between the charging portion of Example 1 and the charging portion of Comparative Example 3. FIG. It is a top view showing a modification of a 1st embodiment of the present invention. It is a perspective view which shows the whole structure of the electrostatic precipitator in the 2nd Embodiment of this invention. FIG. 8 is a perspective view showing the flow of ions when discharge is generated by the discharge electrode in the second embodiment of the present invention; FIG. 10 is a top view showing the flow of ions when a discharge is generated by the discharge electrode in the second embodiment of the present invention; FIG. 5 is a diagram showing the effects of Examples 1 to 3; FIG. 11 is a diagram showing the effects of Examples 4 to 6; FIG. 10 is a diagram specifically showing the difference in effect between the charging unit of Example 6 and the charging unit of Example 4; (a) and (b) are diagrams for explaining the desirable range of the ratio between the width of the leg portion and the width of the top portion of the T-shaped ground electrode according to the second embodiment of the present invention. . (a) and (b) are diagrams for explaining the desirable range of the ratio between the width of the leg portion and the width of the top portion of the T-shaped ground electrode according to the second embodiment of the present invention. .

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[Background and outline of the present embodiment]
Some electrical appliances such as air cleaners and air conditioners are equipped with an electrostatic precipitator that collects airborne particles by charging them with electrical discharge. Such an electrostatic precipitator includes a charging section that charges floating particles by discharge, and a dust collecting section that collects the charged suspended particles. In the charging section, a high voltage of several kV is applied between a high-voltage electrode (discharge electrode) and an opposing ground electrode to generate discharge, and ions generated by the discharge charge the suspended fine particles.

In a charging section having a wire-shaped or needle-shaped discharge electrode, it is necessary to increase the discharge current in order to obtain high dust collection efficiency, and the amount of ozone (O ₃ ) generated with the discharge increases. Since ozone has a peculiar irritating odor, the ozone concentration must be below the environmental standard value (50 ppb) when released indoors. Further, when the discharge electrode is wire-shaped, the electrode may become contaminated during continuous operation, causing the wire to vibrate, causing unpleasant noise and abnormal sparking.

There is also a charging unit in which the discharge electrode is composed of a fibrous conductor, and in this case, the amount of ozone generated can be kept low, but the discharge itself is easily affected by the surrounding conditions of the charging unit, and there is a problem that the performance is unstable. . Moreover, in such a charging unit, since the charging method is mainly based on diffusion charging, it is necessary to secure a wide diffusion space, which makes it difficult to make the charging unit compact.

Therefore, the present embodiment provides a charging device using a fibrous conductor as a discharge electrode, which can obtain high dust collection efficiency and solve problems such as ozone generation, wire vibration, spark generation, and discharge instability. And, an electrostatic precipitator using the charging device is provided. In addition to these, the discharge electrode and the T-shaped plate made of fibrous conductors can solve this problem even in a thin structure of the charging unit, and can simultaneously suppress the charge-up that affects the surroundings of the charging unit. and an electrostatic precipitator using the charging device. Hereinafter, the former will be described as a first embodiment, and the latter as a second embodiment.

[Configuration of electrostatic precipitator in first embodiment]
FIG. 1 is a perspective view showing the overall configuration of an electrostatic precipitator 1 according to this embodiment.

As shown in the figure, the electric dust collector 1 includes a charging section 10, a dust collecting section 30, a fan 40, a housing 50 that houses them, and a high voltage power supply that supplies a high voltage to the charging section 10 and the dust collecting section 30. 60. Here, the housing 50 is indicated by a dashed line so that the configuration of the charging section 10 and the dust collection section 30 provided inside the housing 50 can be seen. This electrostatic precipitator 1 is of a two-stage electrostatic precipitator system in which the functions of the charging section 10 and the dust collecting section 30 are separated. Here, the charging section 10 and the dust collecting section 30 may be configured in the form of a detachable unit. In this embodiment, a charging unit 10 is provided as an example of a charging device.

Here, the direction of air flow (ventilation) is set in the direction from the charging section 10 to the dust collecting section 30 as indicated by the arrow. Ventilation is performed by a fan 40 provided on the downstream side (leeward side) of the dust collecting section 30 in the ventilation direction.

The charging unit 10 includes a plurality of discharge electrodes 11 that generate discharge, a plurality of ground electrodes 12 that are grounded (GND), and a high voltage supplied from a high voltage power supply 60 to the plurality of discharge electrodes 11 . and a power supply member 13 . Since the discharge electrode 11 is an electrode to which a high voltage is applied, it is sometimes called a high voltage electrode. Also, since the ground electrode 12 is provided so as to face the discharge electrode 11, it is sometimes called a counter electrode. The figure shows discharge electrodes 11a to 11f as examples of the plurality of discharge electrodes 11, shows ground electrodes 12a to 12c as examples of the plurality of ground electrodes 12, and shows power supply members 13a and 13b as examples of the plurality of power supply members 13. Although shown, the numbers of discharge electrodes 11, ground electrodes 12, and power supply members 13 are not limited to these.

By the way, in this embodiment, the discharge electrode 11 is formed of a plurality of fibrous conductors. The plurality of fibrous conductors may be, for example, a bundle of 6000 carbon fibers with a fiber diameter of about 7 μm. Then, the rear end of the bundle of carbon fibers is crimped with a crimping portion 14, and the tip is widened like a brush to form the discharge electrode 11. FIG. At this time, the length of the portion of the fibrous conductor protruding from the crimped portion 14 may be, for example, 5 mm, and the length from the tip of the fibrous conductor to the rear end of the crimped portion 14 (the end on the power supply member 13 side) may be, for example, 9 mm. In the figure, each of the discharge electrodes 11a to 11f is configured by crimping a plurality of fibrous conductors with crimping portions 14a to 14f.

Further, in the present embodiment, the discharge electrode 11 is arranged toward the upstream of the treatment airflow. For example, the power supply members 13 each having three discharge electrodes 11 attached at intervals of 95 mm are arranged in two rows such that the tip of the carbon fiber of the discharge electrodes 11 is parallel to the processing gas stream and faces upstream of the processing gas stream. In the figure, the power supply member 13a to which the discharge electrodes 11a to 11c are attached and the power supply member 13b to which the discharge electrodes 11d to 11f are attached are arranged so that the tips of the carbon fibers of the respective discharge electrodes 11 are parallel to the processing gas stream and upstream of the processing gas stream. are placed facing the

Furthermore, in this embodiment, ground electrodes 12 are arranged on both sides of the discharge electrode 11 . That is, the ground electrode 12 is arranged at a position where the ions generated by the discharge at the discharge electrode 11 diffuse toward the upstream side of the processing airflow and cross the processing airflow. In other words, the ground electrode 12 is arranged at a position that attracts the ions generated and diffused by the discharge electrode 11 in the direction intersecting the process gas flow. For example, at a position 60 mm away from the discharge electrode 11 in the direction orthogonal to the processing airflow, the ground electrode 12 having a width of 10 mm is positioned at the rear end of the caulked portion 14 of the discharge electrode 11 and the rear end of the ground electrode 12 (on the downstream side of the processing airflow). ) are aligned with each other. In the drawing, the ground electrode 12a is located on the left side of the power supply member 13a to which the discharge electrodes 11a to 11c are attached in the direction orthogonal to the processing airflow, and the ground electrode 12b is located on the left side of the power supply member 13b to which the discharge electrodes 11d to 11f are attached. is located on the right side in the direction perpendicular to the processing airflow. The ground electrode 12c is arranged on the right side of the power supply member 13a in the direction orthogonal to the processing airflow and on the left side of the power supply member 13b in the direction orthogonal to the processing airflow.

The ground electrode 12 is composed of a plate-like member having conductivity (plate-like conductive member). Further, the ground electrode 12 is provided in a direction in which the flat surface of the flat plate-like member is along the airflow direction. In FIG. 1, the plane of the ground electrode 12 coincides with the airflow direction (the angle between the plane of the ground electrode 12 and the airflow direction is 0°), but the plane does not necessarily have to coincide with the airflow direction.

The dust collection unit 30 includes plate-like high-voltage electrodes 31 whose surfaces are coated with films of an insulating material and plate-like counter electrodes 32 having conductivity, which are alternately laminated. The counter electrode 32 may be of any form as long as it allows the charge of the charged particles to escape, and may be covered with a conductive resin film or the like. The airflow direction is between the high-voltage electrode 31 and the counter electrode 32 . The counter electrode 32 is sometimes called a ground electrode because it may be grounded (GND).

It should be noted that polyethylene, polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), or the like can be used for the insulating material film covering the surface of the high-voltage electrode 31 .

The housing 50 is provided with an inlet portion 51 on the charging section 10 side on the upstream side (windward side) in the ventilation direction, and an outlet section 52 on the dust collecting section 30 side on the leeward side. Incidentally, the entrance portion 51 may be provided with a mesh (net), a lattice, or the like. The mesh (net), grid, or the like provided in the entrance portion 51 is preferably provided so as to prevent the user from contacting the charging portion 10 and have low resistance to drafts. In addition, the inlet portion 51 may be provided with a pre-filter that suppresses entry of large-shaped particles.

The housing 50 is made of a resin material such as ABS (acrylonitrile-butadiene-styrene copolymer).

The fan 40 is provided at an outlet portion 52 on the leeward side provided in the housing 50 . Air flow (ventilation) enters from the inlet 51 of the housing 50 on the side of the charging unit 10, passes through the charging unit 10 and the dust collection unit 30, and exits from the outlet 52 of the housing 50 provided with the fan 40. Get out.

Incidentally, the electric dust collector 1 may be placed in any direction as long as ventilation is not hindered.

The high-voltage power supply 60 applies a direct current (DC) high voltage between the discharge electrode 11 and the ground electrode 12 to generate a corona discharge (discharge) between the discharge electrode 11 and the ground electrode 12. . Then, the ions generated by the generated corona discharge adhere to the suspended particles, thereby electrifying the suspended particles. The high-voltage power supply 60 that applies a high voltage between the discharge electrode 11 and the ground electrode 12 in this manner can also be regarded as part of the charging section 10 .

The high-voltage power supply 60 also applies a direct current (DC) high voltage between the high-voltage electrode 31 and the counter electrode 32 . Then, the suspended fine particles charged by the charging section 10 adhere to the surface of the counter electrode 32 due to electrostatic force. Floating fine particles are thereby collected. The high-voltage power supply 60 that applies a high voltage between the high-voltage electrode 31 and the counter electrode 32 in this manner can also be regarded as a part of the dust collection section 30 .

[Effect of Charging Unit in First Embodiment]
2 and 3 are diagrams showing the flow of ions when a discharge is generated by the discharge electrode 11. FIG. 2 is an enlarged perspective view of the A portion of FIG. 1, and FIG. 3 is a top view of the A portion of FIG. 1 viewed from above. 2 and 3, since positive ions are generated from the discharge electrode 11, the polarity of the high voltage power source 60 (see FIG. 1) is positive.

As shown in the figure, in the present embodiment, the fibrous conductor spreads (spreads like a brush) in the discharge electrode 11, and discharge occurs at the tip of the fibrous conductor. Here, since the amount of discharge at the tip of the fibrous conductor is extremely small, the amount of ozone generated is very low. In addition, the spread of the fibrous conductor allows the ions generated by the discharge to diffuse across the processing airflow, thereby improving the charging efficiency of suspended particles and achieving high dust collection performance.

In addition, in the present embodiment, since discharge is performed at the fine end portion of the fibrous conductor, discharge is possible even if the ground electrode 12 is arranged at a large distance from the discharge electrode 11 . That is, the discharge gap (interval between discharge electrode 11 and ground electrode 12) can be increased. As a result, the corona discharge current (discharge current) is limited, and the transition from corona discharge to arc discharge (spark discharge) is suppressed.

Furthermore, in the present embodiment, the potential is regulated by grounding the ground electrode 12, so that the potential is stabilized. As a result, since the discharge characteristics are less likely to be affected by the surrounding environment, stable discharge can be easily obtained, and the degree of freedom of installation when the electrostatic precipitator 1 is mounted on a product is increased.

In the figure, all of the discharge electrodes 11 are arranged downstream of the most upstream end of the processing airflow of the ground electrode 12, but the present invention is not limited to this. A portion of the discharge electrode 11 may be arranged downstream of the end of the ground electrode 12 on the most upstream side of the processing airflow.

Hereinafter, the charging unit 10 shown in FIG. 1 to FIG. The effect on the charging portion will be described in detail.

First, the effect of diffusion of ions in the upstream direction of the processing airflow and in the direction crossing the processing airflow in Example 1 compared to Comparative Example 1 will be described.

FIG. 4 is a diagram showing the difference between the configuration of the charging unit 10 of Example 1 and the configuration of the charging unit 110 of Comparative example 1. As shown in FIG.

Among them, FIG. 4(a) is an enlarged perspective view of the A portion of FIG. As shown in the figure, the charging unit 10 of the first embodiment comprises a plurality of fibrous conductors crimped by a crimping portion 14, and includes a discharge electrode 11, a ground electrode 12, and a power supply member 13 directed upstream of the processing gas stream. Prepare. 4(b) is an enlarged perspective view of a portion corresponding to part A in FIG. 1 in Comparative Example 1. As shown in FIG. As illustrated, the charging section 110 of Comparative Example 1 includes a wire-shaped discharge electrode 111 and a ground electrode 112 .

FIG. 5 is a graph showing the difference in ion diffusion direction between the charging unit 10 of Example 1 and the charging unit 110 of Comparative example 1. In FIG. From this graph, it can be seen that the ions generated by the charging unit 10 of Example 1 are supplied to the upstream side of the processing airflow and are not supplied to the downstream side of the processing airflow. On the other hand, it can be seen that the ions generated by the charging unit 110 of Comparative Example 1 are supplied to the downstream side of the processing airflow and are not supplied to the upstream side of the processing airflow.

Therefore, since the charging unit 10 of Example 1 employs a composite charging system of electric field charging and diffusion charging, the floating fine particles are charged using the region on the upstream side from the discharge electrode 11 . As a result, a wide charging space can be ensured even in the electrostatic precipitator 1 (see FIG. 1) having the dust collecting section 30 on the downstream side, and high charging efficiency can be easily obtained. On the other hand, in the charging section 110 of Comparative Example 1, since it is of the electric field charging method, the suspended fine particles are charged in a narrow area within the charging space. As a result, in order to obtain high dust collection performance, the discharge current must be increased, and the amount of ozone generated increases.

FIG. 6 is a graph showing the difference in performance regarding the ozone concentration for obtaining the dust collection performance between the charging unit 10 of Example 1 and the charging unit 110 of Comparative example 1. In FIG. From this graph, it can be seen that the charging unit 10 of Example 1 can achieve high dust collection performance with a small discharge current, that is, high dust collection performance can be obtained while suppressing the amount of ozone generated. On the other hand, in the charging unit 110 of Comparative Example 1, sufficient dust collection efficiency cannot be obtained unless the discharge current is increased to such an extent that the ozone concentration exceeds 5 ppb.

Next, the effect of ions diffusing in the direction upstream and crossing the processing airflow in Example 1 compared to Comparative Example 2 will be described.

FIG. 7 is a diagram showing the difference between the configuration of the charging unit 10 of Example 1 and the configuration of the charging unit 210 of Comparative example 2. As shown in FIG.

Among them, FIG. 7(a) is an enlarged perspective view of the A portion of FIG. As shown in the figure, the charging unit 10 of the first embodiment comprises a plurality of fibrous conductors crimped by a crimping portion 14, and includes a discharge electrode 11, a ground electrode 12, and a power supply member 13 directed upstream of the processing gas stream. Prepare. 7(b) is an enlarged perspective view of a portion corresponding to part A in FIG. 1 in Comparative Example 2. As shown in FIG. As shown in the drawing, the charging section 210 of Comparative Example 2 includes a discharge electrode 211 and a ground electrode 212 , which are directed downstream of the processing airflow by crimping a plurality of fibrous conductors with a crimping section 214 .

The ions generated by the charging unit 10 of Example 1 are supplied to the upstream side of the processing airflow. On the other hand, the ions generated by the charging unit 210 of Comparative Example 2 are supplied to the downstream side of the processing airflow. Therefore, the charging unit 10 of Example 1 uses the region on the upstream side from the discharge electrode 11 to charge the suspended particles. As a result, a wide charging space can be ensured even in the electrostatic precipitator 1 (see FIG. 1) having the dust collecting section 30 on the downstream side, and high charging efficiency can be easily obtained. On the other hand, in the charging unit 210 of Comparative Example 2, charging of suspended particles occurs in a narrow area within the charging space. As a result, in order to obtain high dust collection performance, the discharge current must be increased, and the amount of ozone generated increases.

FIG. 8 is a graph showing the difference in performance with respect to discharge voltage for obtaining dust collection performance between the charging unit 10 of Example 1 and the charging unit 210 of Comparative example 2. In FIG. From this graph, it can be seen that the charging section 210 of Comparative Example 2 requires a higher discharge voltage than the charging section 10 of Example 1 in order to obtain the same dust collection performance.

Next, the effect of increasing the discharge gap in Example 1 over Comparative Example 1 will be described.

FIG. 9 is a graph showing the relationship between the discharge gap, the dust collection performance, and the ozone generation performance in the charging section 10 of Example 1. As shown in FIG. From this graph, it can be seen that in the charging unit 10 of Example 1, the dust collection performance increases as the distance between the discharge electrode 11 and the ground electrode 12, that is, the discharge gap, increases. It can be seen that the performance is slightly degraded. Also, it can be seen that the larger the discharge gap, the lower the amount of ozone generated. Specifically, if the discharge gap is 20 mm or more and 100 mm or less, the dust collecting effect is high and the amount of ozone generated is low.

FIG. 10 is a graph showing the relationship between discharge gap and spark resistance. In the graph, the ▴ mark plots the measured values of the discharge gap and the spark over voltage when the spark is generated in the discharge electrode 11 of Example 1, and the □ mark is the spark in the discharge electrode 111 of Comparative Example 1. 1 is a plot of the measured values of the discharge gap and the sparkover voltage when A straight line rising to the right represents the relationship between the discharge gap and the sparkover voltage calculated from these measured values.

In Example 1, as described above, the discharge gap is set to 60 mm. On the other hand, in Comparative Example 1, the discharge gap is assumed to be 10 mm. In the graph, the voltage _V0 for generating a spark when the discharge gap is 60 mm as in Example 1 is the voltage _V1 for generating a spark when the discharge gap is 10 mm as in Comparative Example 1. is about 4.87 times. That is, it is shown that when the distance between the discharge electrode 11 and the ground electrode 12 can be increased as in the first embodiment, abnormalities such as spark generation do not occur.

Next, the effect of obtaining stable discharge without being affected by the ambient environment in Example 1 will be described in comparison with Comparative Example 3. FIG.

FIG. 11 is a diagram showing the difference between the configuration of the charging unit 10 of Example 1 and the configuration of the charging unit 310 of Comparative example 3. As shown in FIG.

Among them, FIG. 11(a) is an enlarged perspective view of a portion A in FIG. As shown in the figure, the charging unit 10 of the first embodiment comprises a plurality of fibrous conductors crimped by a crimping portion 14, and includes a discharge electrode 11, a ground electrode 12, and a power supply member 13 directed upstream of the processing gas stream. Prepare. 11(b) is an enlarged perspective view of a portion corresponding to the portion A in FIG. 1 in Comparative Example 3. As shown in FIG. As shown in the drawing, the charging unit 310 of Comparative Example 3 includes a discharge electrode 311 directed upstream of the processing airflow by crimping a plurality of fibrous conductors with a crimping portion 314 , and a power supply member 313 .

In the charging unit 10 of Example 1, the potential between the discharge electrode 11 and the ground electrode 12 is defined by providing the ground electrode 12 . Compared to the system without the ground electrode 12 as in Comparative Example 3, since the discharge characteristics are not affected by the surrounding environment, it is easy to obtain stable discharge. Therefore, the degree of freedom of installation is increased when the electrostatic precipitator 1 is mounted on a product.

FIG. 12 is a graph showing the difference in performance with respect to discharge voltage for obtaining dust collection performance between the charging unit 10 of Example 1 and the charging unit 310 of Comparative example 3. In FIG. From this graph, it can be seen that the charging section 310 of Comparative Example 3 requires a higher discharge voltage than the charging section 10 of Example 1 in order to obtain the same dust collection performance.

[Modification 1 of the first embodiment]
FIG. 13 is a top view of part A of FIG. 1 as viewed from above, showing a modification of the present embodiment.

In the first embodiment, the ground electrode 12 is arranged in parallel with the processing airflow while the discharge electrode 11 faces the upstream side of the processing airflow, but this is not the only option. In Modification 1, as shown in the figure, the ground electrode 12 is arranged in a direction perpendicular to the processing airflow. Even with such a configuration, the ions generated by the discharge diffuse across the processing airflow, so that the same effect as in the first embodiment can be obtained.

In the figure, all of the discharge electrodes 11 are arranged downstream of the processing airflow from the most upstream end (upstream end face) of the ground electrode 12, but the present invention is not limited to this. . A part of the discharge electrode 11 may be arranged downstream of the most upstream end (upstream end surface) of the ground electrode 12 in the processing airflow.

That is, in the present embodiment, the discharge electrode 11 is arranged between the ground electrodes 12 in the processing airflow, and at least all or part of the plurality of fibrous conductors are positioned at the maximum of the processing airflow of the ground electrode 12 . It suffices if it is arranged on the downstream side of the processing airflow relative to the upstream end.

[Modification 2 of the first embodiment]
In Example 1, the discharge electrode 11 is arranged facing upstream of the treatment airflow, but this is not the only option. In Modified Example 2, the discharge electrodes 11 are arranged facing upstream and downstream of the treatment airflow. In this case, the discharge electrode 11 has a shape combining the discharge electrode 11 shown in FIG. 7A and the discharge electrode 211 shown in FIG. 7B. However, the discharge electrode 11 may be arranged so that at least a portion thereof faces the upstream of the processing airflow. That is, the discharge electrode 11 only needs to include a portion facing the upstream direction of the processing airflow, and may further include a portion facing the downstream direction of the processing airflow.

[Modification 3 of the first embodiment]
In Example 1, the dust collection unit 30 includes a high-voltage electrode 31 and a counter electrode 32, and when a high voltage of direct current (DC) is applied by the high-voltage power supply 60, airborne particles charged by the charging unit 10 are Although the airborne particles are collected by adhering to the surface of the counter electrode 32 by electrostatic force, the present invention is not limited to this. In Modified Example 3, instead of the electrode-type dust collection filter shown in FIG. The former dust collection filter is a type of dust collection filter to which a voltage is applied, while the latter dust collection filter is a type of dust collection filter to which no voltage is applied. Alternatively, a heat exchanger may be used as the dust collector 30 . When using a heat exchanger, for example, the charging unit 10 is arranged at the air inlet of the air conditioner, and the air discharged from the charging unit 10 is passed through the GND-connected (grounded) heat exchanger. Floating fine particles should be removed. When such a dust collector 30 is used, the electric dust collector 1 can be regarded as a dust collector.

[Modification 4 of the first embodiment]
In the first embodiment, only the high voltage power supply 60 that applies a direct current (DC) high voltage between the discharge electrode 11 and the ground electrode 12 is used. As 60, one that applies any of the following high voltages is used.

First, a positive DC high voltage is applied. As a result, dust is less likely to adhere to the discharge electrode 11 and the ground electrode 12, increasing the possibility of prolonging the life of the electrodes.

Secondly, a negative DC high voltage is applied. In general, in corona discharge, the amount of ozone generated in the negative polarity is significantly increased compared to the positive polarity. can be used.

Thirdly, a positive or negative pulse type or alternating type high voltage is applied. As a result, both the effect of applying a positive DC high voltage and the effect of applying a negative DC high voltage can be obtained. Moreover, when a pulse-type high voltage is applied, power is saved.

Fourthly, at predetermined intervals, a high voltage having a polarity opposite to that of the normally applied high voltage is applied. When charging the suspended particles, the charging unit 10 may also charge other peripheral portions (such as the housing 50). Such charge-up of the peripheral portions (casing 50, etc.) of the charging section 10 is alleviated by applying the high voltage as described above.

[Configuration of electrostatic precipitator in second embodiment]
FIG. 14 is a perspective view showing the overall configuration of the electrostatic precipitator 2 in this embodiment.

As illustrated, the electric dust collector 2 includes a charging unit 20, a dust collecting unit 30, a fan 40, a housing 50 that houses them, and a high voltage power supply that supplies high voltage to the charging unit 20 and the dust collecting unit 30. 60. Here, the housing 50 is indicated by a dashed line so that the configuration of the charging section 20 and the dust collecting section 30 provided inside the housing 50 can be seen. This electrostatic precipitator 2 is of a two-stage electrostatic precipitator system in which the charging section 20 and the dust collecting section 30 are separated in function. Here, the charging section 20 and the dust collection section 30 may be configured in the form of a detachable unit. In this embodiment, a charging unit 20 is provided as an example of a charging device.

Here, the direction of air flow (ventilation) is set in the direction from the charging section 20 to the dust collection section 30 as indicated by the arrow. Ventilation is performed by a fan 40 provided on the downstream side (leeward side) of the dust collecting section 30 in the ventilation direction.

The charging unit 20 includes a plurality of discharge electrodes 21 that generate discharge, a plurality of grounded electrodes 22 that are grounded (GND), and a high voltage supplied from a high voltage power supply 60 to the plurality of discharge electrodes 21 . and a power supply member 23 . Since the discharge electrode 21 is an electrode to which a high voltage is applied, it is sometimes called a high voltage electrode. Also, since the ground electrode 22 is provided so as to face the discharge electrode 21, it is sometimes called a counter electrode. The figure shows discharge electrodes 21a to 21f as an example of the plurality of discharge electrodes 21, shows ground electrodes 22a to 22c as an example of the plurality of ground electrodes 22, and shows power supply members 23a and 23b as an example of the plurality of power supply members 23. Although shown, the numbers of discharge electrodes 21, ground electrodes 22, and power supply members 23 are not limited to these.

By the way, in this embodiment, the discharge electrode 21 is formed of a plurality of fibrous conductors. The plurality of fibrous conductors may be, for example, a bundle of 6000 carbon fibers with a fiber diameter of about 7 μm. Then, the rear end of the bundle of carbon fibers is crimped with a crimping portion 24 and the tip is widened like a brush to form the discharge electrode 21 . In this case, the length of the portion of the fibrous conductor that protrudes from the crimped portion 24 may be, for example, 5 mm, and the length from the tip of the fibrous conductor to the rear end of the crimped portion 24 (the end on the power supply member 23 side). may be, for example, 9 mm. In the figure, each of the discharge electrodes 21a-21f is configured by crimping a plurality of fibrous conductors with crimping portions 24a-24f.

Further, in the present embodiment, the discharge electrode 21 is arranged toward the upstream of the treatment airflow. For example, the power supply members 23 each having three discharge electrodes 21 attached at intervals of 95 mm are arranged in two rows such that the tip of the carbon fiber of the discharge electrodes 21 is parallel to the processing gas stream and faces upstream of the processing gas stream. In the figure, the power supply member 23a to which the discharge electrodes 21a to 21c are attached and the power supply member 23b to which the discharge electrodes 21d to 21f are attached are arranged such that the tip of the carbon fiber of each of the discharge electrodes 21 is parallel to the treatment airflow and upstream of the treatment airflow. are placed facing the

Furthermore, in this embodiment, ground electrodes 22 are arranged on both sides of the discharge electrode 21 . Here, the ground electrode 22 is a T-shaped ground electrode composed of a leg portion 25 and a top portion 26 . That is, the T-shaped ground electrode 22 is arranged at a position where the ions generated by the discharge at the discharge electrode 21 diffuse toward the upstream side of the processing airflow and cross the processing airflow. In other words, the T-shaped ground electrode 22 is placed at a position that attracts the ions generated and diffused by the discharge electrode 21 in a direction that intersects the process airflow. For example, at a position 60 mm away from the discharge electrode 21 in the direction orthogonal to the processing airflow, the ground electrode 22 having a leg portion 25 of 10 mm width and a top side portion 26 of 10 mm width is positioned between the crimped portion 24 of the discharge electrode 21 and the rear end thereof. It is arranged so that the rear end of the leg portion 25 of the ground electrode 22 (end portion on the downstream side of the processing airflow) is aligned. In the drawing, a ground electrode 22a consisting of a leg portion 25a and a top side portion 26a is arranged on the left side of the power supply member 23a to which the discharge electrodes 21a to 21c are attached in the direction perpendicular to the processing air flow. A ground electrode 22b consisting of a side portion 26b is arranged on the right side of the power supply member 23b to which the discharge electrodes 21d to 21f are attached in the direction perpendicular to the processing airflow. Further, the ground electrode 22c composed of the leg portion 25c and the top side portion 26c is positioned on the right side of the power supply member 23a in the direction orthogonal to the processing airflow and on the left side of the power supply member 23b in the direction orthogonal to the processing airflow. are placed in

The leg portion 25 and the top side portion 26 are formed of a conductive plate-like member (plate-like conductive member). The leg portions 25 are provided so that the plane of the flat plate-like member extends along the airflow direction, and the top side portion 26 is provided so that the plane of the flat plate-like member intersects the airflow direction. In FIG. 14, the plane of the leg portion 25 is aligned with the airflow direction (the angle between the plane of the leg portion 25 and the airflow direction is 0°). are perpendicular to the airflow direction (the angle formed by the plane of the top side 26 and the airflow direction is 90°), but they do not necessarily have to be perpendicular. In the present embodiment, the leg portion 25 is provided as an example of the flat plate-shaped first electrode portion arranged in the direction along the processing airflow, and the flat plate-shaped second electrode portion arranged in the direction intersecting the processing airflow is provided. A top side portion 26 is provided as an example of the electrode portion. Further, the tip portion of the first electrode portion on the upstream side of the processing airflow and the central portion of the second electrode portion are connected so that the first electrode portion and the second electrode portion are substantially perpendicular to each other. A T-shaped ground electrode 22 is used as an example of the ground electrode formed by.

Although the discharge electrode 21 is arranged between the two adjacent ground electrodes 22 in the above description, the discharge electrode 21 may be arranged in the center between the two adjacent ground electrodes 22 . Also, in the above description, the ground electrode 22 is arranged at a position 60 mm from the discharge electrode 21, but this is not the only option. The ground electrode 22 may be arranged at a position of 20 mm or more and 100 mm or less from the discharge electrode 21 . This is because if the distance from the discharge electrode 21 to the ground electrode 22 is less than 20 mm, the amount of ozone generated increases, and if the distance from the discharge electrode 21 to the ground electrode 22 exceeds 100 mm, dust collection efficiency decreases.

The dust collector 30, the fan 40, the housing 50, and the high-voltage power supply 60 are the same as those described in the first embodiment, so descriptions thereof will be omitted here.

[Effect of Charging Unit in Second Embodiment]
15 and 16 are diagrams showing the flow of ions when discharge is generated by the discharge electrode 21. FIG. 15 is an enlarged perspective view of the portion B of FIG. 14, and FIG. 16 is a top view of the portion B of FIG. 14 viewed from above.

As shown in the figure, in the present embodiment, fibrous conductors are developed in the discharge electrode 21, and discharge occurs at the tips thereof. Here, since the amount of discharge at the tip of the fibrous conductor is extremely small, the amount of ozone generated is very low.

Further, in the present embodiment, the ground electrode 22 is formed in a T-shape composed of the leg portion 25 and the top side portion 26, so that the narrow space between the discharge electrode 21 and the T-shaped ground electrode 22 can be By increasing the electric field strength, ie by increasing the ion density, the diffusion charging efficiency in a narrow space can be improved. Furthermore, it becomes possible to control the diffusion range of the ions to the outer peripheral portion by the top portion 26 . As a result, it is possible to achieve both an improvement in dust collection efficiency and a reduction in peripheral charge-up electrification.

Furthermore, in the present embodiment, the potential is regulated by grounding the ground electrode 22, so the potential is stabilized. As a result, the discharge characteristics are less likely to be affected by the surrounding environment, so stable discharge can be easily obtained, and the degree of freedom of installation when the electrostatic precipitator 2 is mounted on a product is increased.

Furthermore, in the present embodiment, since the fibrous conductor discharges at the fine tip portion, it is possible to discharge even if the ground electrode 22 is arranged at a large distance from the discharge electrode 21 . That is, the discharge gap can be increased. This makes spark discharge less likely to occur.

Hereinafter, the charging unit 10 shown in FIGS. 1 to 3 is defined as Example 1, the charging unit 10 shown in FIG. 13 is defined as Example 2, and the charging unit 20 shown in FIGS. 14 to 16 is defined as Example 3. Examples 4 to 6 are examples in which the discharge electrodes 11 (21) of the charging units 10 (20) of Examples 1 to 3 are perpendicular to the processing airflow, respectively, and Examples 1 to 6. The effect of is explained in detail.

17A and 17B are diagrams showing the effects of Examples 1 to 3. FIG.

In the first to third embodiments, the discharge electrodes 11 (21) are installed in the upstream direction of the treatment airflow, as shown in the discharge electrode installation direction column in the drawing. In this case, the ions generated by the charging section 10 (20) are supplied to the upstream side of the processing airflow.

In the ground electrode column, L1 indicates the width of the planar member (conductive member) in the direction parallel to the processing airflow of the ground electrode 12 (22), and L2 indicates the width perpendicular to the processing airflow of the ground electrode 12 (22). shows the width of the plate-like member (conductive member) in the direction of

1 to 3 and 13 are drawn with the upstream direction of the processing airflow facing upward. That is, in Example 1, as described in the first embodiment, the ground electrode 12 is arranged in a direction parallel to the processing airflow. In Example 2, as described in the modified example of the first embodiment, the ground electrode 12 is arranged in a direction perpendicular to the processing airflow. On the other hand, in Example 3, as described in the second embodiment, the ground electrode 22 is T-shaped and arranged in both the direction parallel to the processing airflow and the direction orthogonal to the processing airflow.

The dust collection efficiency column shows the dust collection efficiency when the wind speed of the processing airflow is 1 m/s. From these values in the dust collection rate and ozone generation amount columns, it can be seen that the dust collection efficiency can be enhanced and the ozone generation amount can be kept low in any of the examples. The charge-up rate column shows the charge-up rate of the housing when Example 1 is set to "1.0". From these charge-up rates, it can be seen that Example 3 can reduce the charge-up the most. Therefore, among the first to third embodiments, the third embodiment is the arrangement that can most improve the dust collection efficiency and reduce the charge-up.

FIG. 18 is a diagram showing the effects of Examples 4 to 6. FIG.

In the fourth to sixth embodiments, the discharge electrodes 11 (21) are installed in the direction orthogonal to the treatment airflow, as shown in the discharge electrode installation direction column in the drawing. In this case, the ions generated by the charging section 10 (20) are mainly supplied in the direction orthogonal to the processing airflow.

In the ground electrode column, the meanings of L1 and L2 are the same as in FIG.

1 to 3 and 13 in which the discharge electrode 11 (21) is perpendicular to the processing airflow is drawn with the upstream direction of the processing airflow facing upward. there is That is, in Example 4, the ground electrode 12 is arranged in a direction parallel to the processing airflow, as described in the first embodiment. In Example 5, the ground electrode 12 is arranged in a direction orthogonal to the processing airflow, as described in the modified example of the first embodiment. On the other hand, in Example 6, similarly to the second embodiment, the ground electrode 22 has a T-shape arranged in both the direction parallel to the processing airflow and the direction orthogonal to the processing airflow. there is

The dust collection efficiency column shows the dust collection efficiency when the wind speed of the processing airflow is 1 m/s. From these values in the dust collection rate and ozone generation amount columns, it can be seen that the dust collection efficiency can be enhanced and the ozone generation amount can be kept low in any of the examples. In addition, the column of charge-up rate shows the charge-up rate of the housing when Example 4 is set to "1.0". From these charge-up rates, it can be seen that Example 6 can reduce the charge-up the most. Therefore, among the fourth to sixth embodiments, the sixth embodiment is the arrangement that can most improve the dust collection efficiency and reduce the charge-up.

FIG. 19 is a diagram specifically showing the difference in effect between the charging unit 20 of Example 6 shown in FIG. 18 and the charging unit 10 of Example 4. In FIG. In FIG. 19, the upper column shows a top view of the charging section configuration column for Examples 4 and 6 in FIG. FIG. 21 is a side view of the figure in the charging section configuration column for Example 6 as seen from the side;

As can be seen from the performance results of FIG. 18 and from FIG. 19 , in Example 6, some of the ion diffusion upstream of the process airflow is suppressed by the edge portion of the T-shaped ground electrode 22 . As a result, compared to the case where the ground electrode 12 is arranged parallel to the processing airflow as in the fourth embodiment, the charging space is less likely to extend upstream of the processing airflow, and charging up to the surroundings of the housing etc. is suppressed. be done. In addition, the electrode area of the T-shaped ground electrode 22 arranged at a certain distance from the tip of the discharge electrode 21 is larger than that of the fourth embodiment, and by increasing the electric field strength in the space, diffusion charging can be performed in a narrow space. Efficiency is improved, ie dust collection efficiency is improved.

In Example 6, as can be seen from the figures in the side column, the tip of the discharge electrode 21 is installed downstream of the end of the ground electrode 22 on the most upstream side (the top side portion 26) of the processing gas flow. is desirable.

[Ratio between the width of the leg portion and the width of the top portion of the ground electrode in the second embodiment]
20(a), (b) and FIGS. 21(a), (b) show the ratio of the width of the leg portion 25 to the width of the top portion 26 of the T-shaped ground electrode 22 in this embodiment. It is a figure for demonstrating a desirable range.

20(a) and 20(b), when the ground electrode 22 in the charging section configuration column for Example 3 in FIG. 17 or the ground electrode 22 in the charging section configuration column for Example 6 in FIG. 18 is viewed from the side. shows the shape of Here, as illustrated, the length of the leg portion 25 is L1, and the length of the top side portion 26 is L2. Among them, FIG. 20A shows the case where the lower end of the leg portion 25 and the lower end of the discharge electrode 21 are at corresponding positions in the direction along the processing airflow, and L1=10 mm. FIG. 20(b) shows a case where the lower end of the leg portion 25 is upstream of the lower end of the discharge electrode 21 in the direction along the processing airflow and L1<10 mm (for example, L1=5 mm). show. In the drawing, the position of the lower end of the discharge electrode 21 is indicated by a dashed line representing the boundary between the charging section 20 and the dust collecting section 30. As shown in FIG.

In FIG. 21(a), L1=10 mm under the condition that the discharge gap is 60 mm and the lower end of the leg portion 25 of the ground electrode 22 and the lower end of the discharge electrode 21 are aligned in the direction along the processing air flow. , and the change in the dust collection efficiency and the charge-up rate when the length of L2 is changed is shown in a graph.

First, from the solid line graph showing changes in dust collection efficiency, it can be seen that the dust collection efficiency is 90% or more when L2/L1≦1. Here, the reason why the dust collection efficiency is lowered when L2/L1 is increased is that the distance between the end of the top side portion 26 and the tip of the discharge electrode 21 is shortened, so that the diffusion distance of ions is insufficient. and the charging efficiency decreases.

Next, from the graph showing changes in the charge-up rate indicated by the dashed line, it can be seen that the charge-up rate is 0.7 or less when 0.4≦L2/L1.

Therefore, it can be seen that the ratio L2/L1 is preferably a value that satisfies 0.4≦L2/L1≦1.

In FIG. 21(b), L1=5 mm under the condition that the discharge gap is 60 mm and the lower end of the leg portion 25 of the ground electrode 22 is upstream of the lower end of the discharge electrode 21 in the direction along the processing air flow. , and the change in the dust collection efficiency and the charge-up rate when the length of L2 is changed is shown in a graph.

First, from the solid line graph showing changes in dust collection efficiency, it can be seen that the dust collection efficiency is 90% or more when L2/L1≦2.

Next, from the graph showing changes in the charge-up rate indicated by the dashed line, it can be seen that the charge-up rate is 0.7 or less when 0.4≦L2/L1.

Therefore, it can be seen that the ratio L2/L1 is preferably a value that satisfies 0.4≦L2/L1≦2.

[Modification 1 of Second Embodiment]
In Examples 1 to 3, the discharge electrode 11 (21) is arranged facing upstream of the treatment airflow, and in Examples 4 to 6, the discharge electrode 11 (21) is arranged in a direction perpendicular to the treatment airflow. However, it is not limited to this. In Modified Example 1, for example, when a dust collection filter made of fibers is used as the dust collection section 30, the discharge electrode 11 (21) is arranged toward the downstream of the processing airflow. Alternatively, in Modification 1, for example, the discharge electrodes 11 (21) may be arranged obliquely with respect to the direction along the processing airflow. For example, it may be arranged at an angle of 45° with respect to the upstream direction of the processing airflow, or at an angle of 45° with respect to the downstream direction of the processing airflow.

[Modification 2 of Second Embodiment]
Modifications 3 and 4 of the first embodiment are similarly applicable to the second embodiment.

DESCRIPTION OF SYMBOLS 1... Electric dust collector 10, 20... Charging part 11, 21... Discharge electrode 12, 22... Ground electrode 13, 23... Power supply member 14, 24... Crimping part 25... Leg part 26... Top side part , 30... dust collecting part, 40... fan, 50... housing, 60... high voltage power supply

Claims (12)

a discharge electrode formed of a plurality of fibrous conductors for generating and diffusing ions by discharge;
a ground electrode that is maintained at a ground potential, attracts ions generated and diffused by the discharge electrode, and charges suspended fine particles contained in the processing gas stream with the ions;
The discharge electrodes are disposed between the ground electrodes in the process airflow, and at least all or part of the plurality of fibrous conductors of the discharge electrodes are located on the most upstream side of the process airflow of the ground electrodes. is arranged downstream of the processing airflow from the end of the
The ground electrode includes a flat plate-shaped first electrode section arranged in a direction along the processing airflow, and a flat plate-shaped second electrode section arranged in a direction intersecting the processing airflow. charging device. The ground electrode is arranged between the tip portion of the first electrode portion on the upstream side of the processing airflow and the second electrode portion so that the first electrode portion and the second electrode portion are substantially perpendicular to each other. 2. The charging device according to claim 1 , wherein the charging device is formed by connecting the central portion of the charging device with the central portion of the charging device. When the length of the first electrode portion in the direction along the processing airflow is L1, and the length of the second electrode portion in the direction toward the discharge electrode is L2, the ground electrode has a value of 0.0. 3. The charging device according to claim 2, wherein 4≤L2/L1≤2. 1. The discharge electrodes are arranged in the center between two adjacent ground electrodes so that the distance to any of the ground electrodes is 20 mm or more and 100 mm or less. 4. The charging device according to any one of items 3 . 2. The charging device according to claim 1 , wherein said plurality of fibrous conductors are carbon fibers. 2. The charging device according to claim 1, further comprising a high voltage power source for applying a high voltage between said discharge electrode and said ground electrode. 7. The charging device according to claim 6 , wherein the high voltage power supply applies a positive or negative DC high voltage between the discharge electrode and the ground electrode. 7. The charging device according to claim 6 , wherein the high-voltage power supply applies a positive or negative pulse-type or alternating-type high voltage between the discharge electrode and the ground electrode. 7. The high voltage power supply according to claim 6 , wherein the high voltage power supply applies a high voltage opposite in polarity to a normally applied high voltage at a predetermined interval between the discharge electrode and the ground electrode. charging device. a charging device according to any one of claims 1 to 9 ;
A dust collector, comprising: a dust collector that collects dust by adhering floating fine particles charged by the charging device. 11. The dust collector according to claim 10 , wherein the dust collector is configured by a dust filter. 11. The dust collector according to claim 10 , wherein the dust collector comprises a heat exchanger.

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