JPH078746A - Cleaning/deodorizing system using electrostatic flocculation device for cleaning and deodorizing exhaust gas generated from coating booth - Google Patents

Abstract

PURPOSE:To provide a cleaning/deodorizing system using an electrostatic flocculation device for cleaning and deodorizing exhaust gas generated from a coating booth. CONSTITUTION:Water is ionized into an electrolytic solution by allowing exhaust gas generated in a water wash-type coating booth to by led to a scrubber 8 by an exhaust fan 6 and a duct 7 and pass through an electrostatic flocculation device 11 which forms an electrostatic field, from a water tank 9 using pump 10. Next, this electrolytic solution is sent is sent to a shower nozzle 13 and is atomized in the upper part of the scrubber 8. The exhaust gas ascends from the lower part of the scrubber 8, and become cleaned through the contact with the electrolytic solution when the exhaust gas passes through a resinfilled layer 15. In this case, an odoriferous component is decomposed into carbon dioxide and water by the electrolytic solution and electrochemical reaction, and is thus deodorized.

Description

Detailed Description of the Invention

[0001]

[Industrial application] There are dry booths and water-washing booths in both coating booths, both of which contain solvent gas in the exhaust gas and may generate odor depending on the type of paint. For the generation of odor, it is desirable to use a deodorizing device together. The present invention relates to a cleaning and deodorizing system that cleans exhaust gas generated from a coating booth using water that has become an electrolytic solution through an electrostatic coagulator to perform deodorization.

[0002]

2. Description of the Related Art When using an organic solvent in a coating booth,
There are emission regulations related to air pollution control, so these emission regulations must be observed. There are nozzle type, no pump type, Venturi type, etc. in the water-washing type paint booth, and the paint mist generated during painting work is attracted to the washing tower and exhausted. The paint mist is absorbed by water in the washing tower and dropped into the water tank. In the dry booth, the paint mist is adsorbed on the filter and collected, and then exhausted. It is possible to keep the organic solvent below the emission control value by the coating booth. Although there is a possibility that regulations will be implemented in the future with regard to the prevention of offensive odors, at present, only when there is a complaint from the neighborhood, the local government measures whether or not the regulated substance exceeds the regulated value at the boundary line of the factory site and confirms the violation. I have decided whether or not. Even if the regulated substance is below the regulated value, there is a sense to the odor, and the deterioration of the social image of the company due to complaints should be avoided as much as possible. It is considered that neighborhood measures against bad odors will be important in the future. . In addition, there is a great need to prevent foul odors at urban factories. As a deodorizing device for preventing a bad odor, there are a direct combustion method, a catalytic combustion method, an activated carbon adsorption method and an absorption method. Since the direct combustion method and the catalytic combustion method are high-temperature treatments, they have excellent deodorizing effects, but they require a great deal of money in consideration of emission prevention of nitrogen oxides and effective utilization of exhaust heat. The activated carbon adsorption method is limited to low-temperature and low-concentration exhaust gas, and depending on the component, it may be difficult to treat. The absorption method has low equipment costs and running costs, but the deodorizing effect is poor, and wastewater treatment is required.

[0003]

The conventional absorption method of a deodorizing device is a method of absorbing exhaust gas with a cleaning liquid to remove a malodorous component, and a chemical liquid may be used to improve the effect. According to the present invention, by cleaning the exhaust gas with an electrolyte solution,
It utilizes that the malodorous component is removed by an electrochemical reaction. According to the present invention, the organic solvent component generated from the coating booth reacts and decomposes into carbon dioxide and water, and the malodorous component is removed. The electrolyte solution is recycled by using a pump. Since no chemicals are used, pollution of the electrolyte solution is small, long-term operation is possible, and wastewater treatment is reduced. Equipment costs and running costs are low, and the installation space is small, so it is easy to install in existing equipment.

[0004]

In order to achieve the above object, the deodorizing system of the present invention comprises a duct for attracting exhaust gas from a coating booth, a washing tower (scrubber), a water tank, a circulation pump, and an electrostatic coagulator. Equipped. Water is sucked from the water tank with a pump and sent to the electrostatic coagulator. The electrostatic coagulator forms an electrostatic field by supplying DC power.
Water is ionized into an electrolyte solution. The electrolyte solution is sprayed on top of the scrubber. A duct that connects to the painting booth is installed under the scrubber, and exhaust gas containing organic solvent is sent to the scrubber from an exhaust fan.

[0005]

[Operation] When exhaust gas is sent from the coating booth to the deodorizing system configured as described above, the exhaust gas comes into contact with the electrolyte solution in the process of rising in the scrubber, is washed by the electrochemical reaction and absorption action, and the malodorous components are removed. Be disassembled.

[0006]

EXAMPLE An example of a water-washing type coating booth will be described with reference to the drawings. In FIG. 1, an object to be coated (2) carried by a conveyor (3) is a water-washing type coating booth (1).
It is painted with a paint spray gun. A coating film is formed on the object to be coated (2) by this spraying work, but at the same time, excess paint mist is generated. This paint mist is exhausted by an exhaust fan (6) installed in the cleaning tower (4). The paint mist is absorbed by water in the washing tower (4) and dropped into the water tank (5). Exhaust gas is drawn from the exhaust fan (6) to the scrubber (8) through the duct (7). The water in the water tank (9) is sucked by the circulation pump (10) and sent to the electrostatic coagulator (11). The electrostatic coagulator (11) is equipped with a high voltage generator,
When three-phase 200V is supplied from 2) to the commercial power source, a high voltage is generated and an electrostatic field is formed. When water passes through the electrostatic field, ionization occurs and the water becomes an electrolytic solution. A part of this electrolytic solution is returned to the water tank (9), and the other is a shower nozzle (13).
Send to. When painting is not performed at night, it is not necessary to feed liquid to the shower nozzle (13), so the valve (18)
Is fully closed, and all the water that has passed through the electrostatic coagulator (11) is returned to the water tank (9). When the exhaust gas attracted to the scrubber (8) is passed through the resin-filled layer (15) and raised, the contact time with the electrolytic solution sprayed from the shower nozzle (13) increases and the cleaning and deodorizing effect increases. . The exhaust gas is decomposed into carbon dioxide and water by an electrochemical reaction with the electrolytic solution and deodorized. The drain plate (14) is provided to prevent the shower from splashing outside.

In FIG. 1, the valve (16) is installed at the pump outlet to adjust the amount of liquid fed to the electrostatic coagulator (11).
The valve (19) is for adjusting the shower, the aquarium (9)
When the water level becomes high, it overflows from the overflow pipe (21) and is drained. The valve (20) is fully opened when the water tank (9) is cleaned and the solution is extracted.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a deodorizing system for a water-washing type coating booth.

[Explanation of symbols]

 1 Water-washing type coating booth 2 Object to be coated 3 Conveyor 4 Cleaning tower 5 Water tank 6 Exhaust fan 7 Duct 8 Scrubber 9 Water tank 10 Circulation pump 11 Electrostatic coagulator 12 DC power supply 13 Shower nozzle 14 Drain plate 15 Resin filling layer 16 Valve 17 valves 18 valves 19 valves 20 valves 21 overflow pipes

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[Procedure amendment]

[Submission date] January 6, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Added

[Correction content]

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a deodorizing system for a water-washing type coating booth.

[Explanation of Codes] 1 Water-washing type coating booth 2 Object to be coated 3 Conveyor 4 Cleaning tower 5 Water tank 6 Exhaust fan 7 Duct 8 Scrubber 9 Water tank 10 Circulation pump 11 Electrostatic coagulator 12 DC power supply 13 Shower nozzle 14 Drain plate 15 Resin-filled layer 16 valves 17 valves 18 valves 19 valves 20 valves 21 overflow pipes

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Added

[Correction content]

[Figure 1]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B05B 15/12 6977-4D C02F 1/46 Z 9344-4D

Claims (1)

[Claims] 1. An electrostatic electric field formed by an electrostatic coagulator is passed through water pressurized by a pump to form an electrolytic solution, and the exhaust gas generated from a coating booth is washed with this water to carry out an electrochemical reaction and Cleaning and deodorizing system that cleans and deodorizes by absorption