JP3973764B2 - Electric dust collector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electric dust collector having a large air volume installed in a closed space such as an automobile road tunnel or an underground parking lot.
[0002]
[Prior art]
Conventionally, what is described in Japanese Patent Application Laid-Open No. 55-8826 is known as an electric dust collector of this type.
[0003]
The electric dust collector will be described below with reference to FIG. In other words, a high voltage electrode 101 and a ground electrode 102 are provided in the path of the gas to be treated, and a DC high voltage is applied between both electrodes to cause discharge, and dust charged by the discharge is collected on the dust collection electrode 103. A particle neutralizer is provided at the outlet of the electrostatic precipitator to be collected. This particle neutralizing device is provided with a discharge electrode (ground electrode) 104 and a high voltage electrode 105 made of fine wires that generate a discharge with a reverse polarity to the discharge that charges the dust, and further a discharge with a reverse polarity discharge performed by the discharge electrode moving mechanism 106. A control device 108 is provided which controls the output of reverse polarity discharge by moving the electrode 104 or changing the variable high resistance 107 connected in series to the discharge electrode 104. This particle neutralizer eliminates the charged dust that flows out without being collected by the electrostatic precipitator, and reduces contamination caused by this dust adhering to the equipment and structures on the outflow side of the electrostatic precipitator. ing.
[0004]
[Problems to be solved by the invention]
In such a conventional electrostatic precipitator, there is a problem that the structure is complicated, it takes time and labor for production and maintenance, and there is a problem of power consumption. It is requested.
[0005]
The present invention solves such a conventional problem, and can practically remove the charged dust that has passed without being collected by the dust collection unit. It is an object of the present invention to provide an electrostatic precipitator that has a simple structure that can reduce contamination caused by adhering to a structure, etc., energy saving, and easy maintenance.
[0006]
[Means for Solving the Problems]
For the electrical precipitator of the present invention to achieve the above object, it charges the dust contained in the airflow, and dust collector unit for collecting, downstream thereof, in order from the upstream side, cleaning unit, is grounded In addition, the structure includes a wire mesh and a damper .
[0007]
According to the present invention, the charged dust that has passed without being collected by the dust collection unit is brought into contact with the grounded metal mesh, and the charged dust is discharged to the ground side through the metal mesh, thereby removing the dust. , It is possible to reduce contamination caused by dust adhering to facilities and structures on the outflow side of the electrostatic precipitator, and by regularly cleaning the metal mesh by the cleaning unit, dust that comes in contact with the metal mesh adheres to the metal mesh. Thus, an electric dust collector capable of preventing clogging of the wire mesh due to the above is obtained.
[0008]
In order to achieve the above object , the electric dust collector of the present invention is configured to have a wire mesh to which a low voltage having a polarity opposite to that of the dust collecting unit is applied.
[0009]
According to the present invention, a Coulomb force is generated between the charge of the charged dust that has passed without being collected by the dust collection unit and the charge of the wire mesh to which a voltage is applied, and the dust charged by this Coulomb force is This increases the probability that the charged dust will come into contact with the wire mesh, increase the charge removal effect of the charged dust, and the dust will adhere to the equipment and structures on the outflow side of the electrostatic precipitator. Thus, an electrostatic precipitator can be obtained that can further reduce contamination due to the above.
[0010]
In order to achieve the above object, the electrostatic precipitator of the present invention is configured to include a wire mesh covered with conductive flagella.
[0011]
According to the above , by increasing the contact area between the charged dust that has passed without being collected by the dust collecting unit and the wire mesh, the frequency of contact between the charged dust and the wire mesh is increased, and the charged dust An electrostatic precipitator can be obtained that can increase the charge removal effect and can further reduce contamination caused by dust adhering to facilities and structures on the outflow side of the precipitator.
[0012]
Moreover , the electric dust collector of the present invention is configured to include a dust adhesion degree detection unit and a cleaning control unit on the wire mesh.
[0013]
According to the above , it is possible to obtain an electric dust collector capable of performing automatic cleaning in a timely manner by detecting the degree of dirt on the wire mesh.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is provided with a dust collection unit that charges and collects dust, and a grounded metal mesh and a cleaning unit that cleans the metal mesh on the downstream side of the dust collection unit, and is collected by the dust collection unit. By contacting the charged dust that has passed without contact with the grounded metal mesh and removing the static electricity, contamination due to this dust adhering to the equipment and structures on the outflow side of the electrostatic precipitator can be reduced, and the cleaning section By cleaning the metal mesh, the metal mesh can be prevented from being clogged due to the dust coming into contact with the metal mesh adhering to the metal mesh.
[0015]
The metal mesh is applied with a low voltage of reverse polarity to the dust collection unit, and the charged dust that has passed through the dust collection unit without being collected is brought into contact with the wire mesh to remove the charged uncollected dust. It has the effect | action that it can neutralize more effectively.
[0016]
Further, the metal mesh is covered with conductive flagellum, and thus has an effect that the charged dust that has passed without being collected by the dust collection unit can be more effectively removed.
[0017]
In addition, a dust adhesion degree detection unit and a cleaning control unit are provided, and a signal indicating the degree of adhesion of the dust that has passed without being collected by the dust collection unit output from the dust adhesion detection unit to the metal mesh. When the preset value is exceeded, the cleaning control unit outputs a wire mesh cleaning signal, and this signal has an effect of automatically cleaning the wire mesh in a timely manner.
[0018]
Embodiments of the present invention will be described below with reference to the drawings.
[0019]
【Example】
Example 1
FIG. 1 shows an electrostatic precipitator according to a first embodiment of the present invention. A housing 1 of the electric dust collector is provided with doors 2 on the front and rear sides, and an inlet damper 3, a dust collector unit 4, and an outlet damper 5 are arranged in this order from the air flow inflow side. The dust collection unit 4 includes a charging unit 7 that charges dust contained in the air flow and a dust collection unit 8 that collects the charged dust. A dust collection unit cleaning nozzle 6 is provided around the dust collection unit 4. Has been placed. Further, a metal mesh 9 is provided between the dust collection unit washing nozzle 6 on the downstream side of the dust collection unit 4 and the outlet damper 5, and the metal mesh 9 is grounded on the entire surface of the air flow path in a direction orthogonal to the air flow. The wire mesh 9 is made of stainless steel having a wire diameter of 0.2 mm and mesh # 16, and is grounded. A wire mesh cleaning nozzle 6 </ b> A is provided on the upstream side of the wire mesh 9.
[0020]
In the above configuration, the charging unit 7 generates a corona discharge between a discharge line (not shown), which is a high-voltage electrode arranged in parallel at a predetermined interval, and a ground electrode plate (not shown), and is generated by the corona discharge. As the ions collide with the dust, the dust is charged. The dust collection unit 8 has a configuration in which a load electrode plate (not shown) and a ground electrode plate (not shown) are alternately stacked in parallel at the same electrode plate interval. By applying a high voltage having the same polarity as the discharge line, an electric field is generated between the load electrode plate and the ground electrode plate, and the charged dust is collected on the ground electrode plate under the force of the electric field. The charged dust that has passed without being collected by the dust collection unit 4 comes into contact with the grounded wire mesh 9 and passes through the wire mesh 9 or remains attached to the wire mesh 9. A part of the charged dust passes without contacting the metal mesh 9. The charge of the charged dust coming into contact with the grounded wire mesh 9 moves to the ground side through the wire mesh 9, so that the total charge amount of the entire dust is reduced. Further, as a result of the experiment, it was confirmed that the amount of uncollected dust that has passed through the dust collection unit 4 is reduced by about 60% compared to the amount before the installation of the wire mesh 9 on the facilities and structures on the downstream side of the housing 1. .
[0021]
For cleaning the dust collection unit 4, after applying voltage to the dust collection unit 4 is stopped, cleaning water is sprayed from the dust collection unit cleaning nozzle 6 to remove dust accumulated in the dust collection unit 4. Also, the metal mesh 9 is clogged by stopping the application of voltage to the dust collecting unit 4 and then spraying cleaning water from the metal mesh cleaning nozzle 6A to remove dust accumulated on the metal mesh 9. Can be prevented. The dust removed from the dust collection unit 4 and the wire mesh 9 by washing passes through a drainage duct (not shown) together with the washing water and is sent to a sewage treatment device (not shown), and is separated into dust and water by the sewage treatment device. Is done.
[0022]
FIG. 4 shows a state in which cleaning water is jetted from the wire mesh cleaning nozzle 6A with the outlet damper 5 closed. By closing the outlet damper 5 when the cleaning water is sprayed from the wire mesh cleaning nozzle 6A, it is possible to prevent the sewage containing dust accumulated on the wire mesh 9 from being scattered outside the housing 1, and the cleaning water is discharged from the outlet. The dust that has bounced off the damper 5 and bounced back is also removed by the splashed washing water. Therefore, when the washing water is jetted from the wire mesh washing nozzle 6A, the operation of the outlet damper 5 is interlocked and the outlet damper 5 is closed, so that the washing can be efficiently performed with a small amount of washing water and the wire mesh 9 is prevented from being clogged. can get.
[0023]
Therefore, it is possible to remove the charged dust that has passed without being collected by the dust collection unit, and to reduce the contamination caused by the dust adhering to facilities and structures on the outflow side of the dust collector. An electric dust collector that can be easily maintained can be provided.
[0024]
In addition, you may change the wire diameter and mesh of the metal mesh 9 according to the target static elimination effect. The metal mesh 9 may be provided in a plurality of stages on the downstream side of the dust collection unit 4. Further, the wire mesh 9 may be provided on the downstream side (outside the casing) from the outlet damper 5.
[0025]
A water pipe for supplying cleaning water to the dust collection unit cleaning nozzle 6 and the wire mesh cleaning nozzle 6A may be shared. Alternatively, the metal mesh cleaning nozzle 6A may be installed above the metal mesh 9 and the cleaning water may be dropped. Further, the wire mesh 9 can be cleaned by connecting the wire mesh cleaning nozzle 6A to an air pipe and injecting compressed air.
[0026]
(Example 2)
FIG. 2 shows an electric dust collector according to a second embodiment of the present invention. Here, the description of the points common to the first embodiment will be omitted. The wire mesh 9 is connected to a DC power source 10 and applied with a low voltage (for example, 24 V) having a polarity opposite to the high voltage applied to the dust collection unit 4.
[0027]
In the above configuration, by applying a voltage to the wire mesh 9, the charge of the charged dust that has passed without being collected by the dust collecting portion 8 and the charge of the wire mesh 9 to which a voltage having a polarity opposite to that of the charged dust is applied. Coulomb force is generated between them. Due to this Coulomb force, a force that attracts the charged dust to the wire mesh 9 is generated, and the probability that the charged dust comes into contact with the wire mesh 9 is increased, and the charge eliminating effect of the charged dust can be increased. (1) Contamination due to adhering to facilities and structures on the outflow side can be further reduced.
[0028]
(Example 3)
FIG. 3 is a partial front view of a wire mesh according to a third embodiment of the present invention. It should be noted that the description of the points common to the first and second embodiments is omitted here. In this embodiment, the grounded wire mesh 9 is provided with a flagella 11 having conductivity.
[0029]
In the above configuration, by attaching the flagella 11 to the wire mesh 9, the area where the uncollected charged dust contacts the wire mesh 9 is increased, and the contact probability between the charged dust and the wire mesh 9 is increased. The charge removal effect due to the movement of the dust charges to the wire mesh 9 can be increased, and the contamination due to the dust adhering to the equipment and structures on the outflow side of the housing 1 can be further reduced.
[0030]
Example 4
FIG. 5 shows an electric dust collector according to a fourth embodiment of the present invention. Description of points common to the first embodiment, the second embodiment, and the third embodiment is omitted. The electric dust collector of the present embodiment is provided with a dust adhesion degree detection unit 14 for detecting the degree of dust adhesion on the wire mesh 9, and the dust adhesion degree detection unit 14 includes a pressure detection tube 12 and a differential pressure gauge 13. .
[0031]
In the above configuration, the pressure detection tube 12 is installed around the housing 1 of the electric dust collector, and the differential pressure across the housing 1 is detected by the differential pressure gauge 13 connected to the pressure detection tube 12. The differential pressure signal from the differential pressure gauge 13 is input to the cleaning control unit 15, and when this differential pressure signal (analog signal) exceeds a set value, the voltage applied to the dust collection unit 4 is applied by the electrical signal from the cleaning control unit 15. Stop and close the outlet damper 5. Thereafter, the water pipe valve 16 of the wire mesh cleaning nozzle 6A is opened by an electrical signal from the cleaning control unit 15, and the cleaning of the wire mesh 9 is started. Therefore, an appropriate cleaning start time can be set, and the wire mesh 9 can be automatically cleaned in a timely manner.
[0032]
【The invention's effect】
As is clear from the above embodiments, according to the present invention, a grounded metal mesh and a cleaning unit for cleaning the metal mesh are provided on the downstream side of the dust collection unit, so that the dust collector passes without being collected. The charged dust can be neutralized and the wire mesh can be prevented from being clogged. Therefore, the structure that can reduce the contamination caused by the charged dust that has passed without being collected by the dust collection unit adheres to the equipment and structures on the outflow side of the dust collector, and has a simple structure, energy saving and easy maintenance. An apparatus can be provided.
[0033]
In addition, by applying a low voltage with a polarity opposite to that of the dust collection unit to the metal mesh, the dust charged by the Coulomb force generated between the charge of the charged dust that passes without being collected by the dust collection unit and the charge of the metal mesh Is attracted to the wire mesh, and the contact probability between the charged dust and the wire mesh increases, so that the charge removal effect of the charged dust can be increased, and the dust is transferred to facilities and structures on the outflow side of the electrostatic precipitator. Contamination due to adhesion can be further reduced.
[0034]
In addition, by grounding the wire mesh with conductive flagella to the downstream side of the dust collection unit, the contact area between the charged dust and the wire mesh that have passed without being collected by the dust collection unit increases, and the charged dust By increasing the probability of contact between the metal mesh and the metal mesh, the effect of neutralizing charged dust can be increased, and contamination caused by the dust adhering to facilities and structures on the outflow side of the electric dust collector can be further reduced.
[0035]
In addition, by providing a dust-meshing degree detection unit and a cleaning control unit for the metal mesh, the degree of contamination of the metal mesh can be detected, automatic cleaning can be performed in a timely manner, and maintenance can be further improved.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a configuration of Example 1 of the present invention. FIG. 2 is a side sectional view showing a configuration of Example 2. FIG. 3 is a partial front view showing a configuration of Example 3. 4] Side view of the main part showing the configuration of the first embodiment. [FIG. 5] FIG. 6 is a diagram for explaining the configuration of the fourth embodiment. [FIG. 6] FIG.
DESCRIPTION OF SYMBOLS 1 Housing | casing 2 Door 3 Inlet damper 4 Dust collection unit 5 Outlet damper 6 Dust collection unit washing nozzle 6A Wire mesh washing nozzle 7 Charging part 8 Dust collection part 9 Wire net 10 DC power supply 11 Flagella 12 Pressure detection tube 13 Differential pressure gauge 14 Dust adhesion degree Detection unit 15 Cleaning control unit 16 Water piping valve 101 High voltage electrode 102 Ground electrode 103 Dust collecting electrode 104 Discharge electrode 105 High voltage electrode 106 Discharge electrode moving mechanism 107 Variable high resistance 108 Control device

Claims (2)

A dust collection unit that charges and collects dust contained in the air flowing into the housing and the housing;
Its downstream, in order from the upstream side, cleaning section, wire mesh which is grounded, electrostatic precipitators device that includes a damper.   2. The electric dust collector according to claim 1, wherein a low voltage having a polarity opposite to that of the dust collecting unit is applied to the wire mesh.

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