JP3381320B2 - Freon gas treatment equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chlorofluorocarbon gas treating apparatus for decomposing fluorocarbon gas by utilizing electric discharge.

[0002]

2. Description of the Related Art Freon gas used in semiconductors, precision machinery, refrigerant related industries, etc. causes destruction of the ozone layer. Therefore, various treatment methods for CFCs have been studied. For example, a combustion / fuel decomposition method in which CFCs are burned using a combustion improver (for example, methane), a catalytic decomposition method in which CFCs are decomposed by a heated catalyst, and a critical point of water (373
There are a supercritical water method of decomposing at 218 ° C. or higher), a plasma decomposition method of decomposing with high temperature plasma by high frequency induction, and the like.

However, all of these fluorocarbon processing methods require processing at high temperature and high pressure, and the processing equipment becomes expensive and complicated.

Therefore, in recent years, an electric discharge decomposition method for decomposing CFCs by electric discharge has attracted attention. In the discharge decomposition method, a discharge electrode and an induction electrode are arranged to face each other via a dielectric,
By applying a pulse voltage between these electrodes, a discharge is generated in the gap between both electrodes, and the CFC gas passing therethrough is decomposed. According to this treatment method, the chlorofluorocarbon gas can be decomposed at room temperature and atmospheric pressure and only by electric means, so that the chlorofluorocarbon gas treatment device can be manufactured easily and inexpensively.

However, in order to improve the efficiency of CFC decomposition, it has been attempted to form a water film instead of the dielectric material on the inner surface of the induction electrode and dissolve it in the water film.

[0006]

However, when a water film is used in the electric discharge decomposition method, the decomposition products of fluorocarbons (H
It has been found that F, HCl, etc.) are generated and the dielectric electrode is corroded. Therefore, an absorption device for absorbing the decomposition products must be separately provided, which increases the size and cost of the device.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to provide a CFC gas treatment apparatus which can improve the efficiency of CFC gas decomposition and can be downsized.

[0008]

In order to achieve the above object, the present invention relates to a CFC gas treating apparatus for decomposing CFC gas by utilizing an electric discharge, and a cylinder made of synthetic resin such as vinyl chloride for introducing and discharging CFC gas. The body, the discharge electrode provided in the cylinder, and the surface-active agent on the inner surface of the cylinder.
And a square-wave pulse voltage power supply for applying a square-wave pulse voltage between the water film and the discharge electrode. The invention of claim 2 is
In addition to the constitution described in 1, the concentration of the surfactant is about 100 p.
It is preferably pm.

[0009]

According to the above construction, the water film as the electrode dissolves the decomposition products of CFCs generated by the discharge, so that the decomposition efficiency is improved, and the cylinder for introducing and discharging the CFC gas is made of vinyl chloride or the like. As it is made of synthetic resin, it is prevented from being corroded by the decomposition products of CFC,
It is not necessary to provide an absorption device for absorbing the decomposition products. Therefore, the device is downsized and simplified.

[0010]

An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a schematic view of an embodiment of the fluorocarbon processing apparatus of the present invention.

In FIG. 1, reference numeral 1 is a cylinder made of synthetic resin such as vinyl chloride. A blower 2 for supplying a gas containing chlorofluorocarbon into the cylindrical body 1 is connected to the lower portion of the cylindrical body 1 through a pipe 3. A pipe 4 is connected to an upper portion of the cylinder 1 to release a gas in which CFCs are decomposed.

A rod-shaped discharge electrode 5 is provided at the center of the cylindrical body 1. This discharge electrode is provided outside and is a square wave pulse voltage power source (for example, 400H) for generating a corona discharge.
z, about 10 KV) 6 is connected.

A water film forming means 8 for forming a water film 7 which flows down along the inner surface of the cylinder 1 is provided on the inner surface of the cylinder 1. The water film forming means 8 is composed of a dam 9 provided on the upper portion of the inner surface of the cylindrical body 1 and a water supply pump 10 for supplying water to the dam 9. Further, a container 11 capable of recovering the water forming the water film 7 and discharging a part thereof is connected to the lower portion of the cylindrical body 1. The water film 7 and the water collected in the container 11 are electrically connected to each other, and the water in the container 11 is grounded. That is, the water film 7 functions as a ground electrode. A pipe 12 for returning the collected water to the water supply pump 10 for circulation is connected to the container 11.
The temperature of the water film in the cylindrical body 1 is preferably high enough to prevent boiling (eg, 80 ° C.).

Next, the operation of the embodiment will be described.

When a gas containing chlorofluorocarbon is introduced into the cylindrical body 1 by the blower 2, the chlorofluorocarbon gas flows upward in the cylindrical body 1. In this cylindrical body 1, corona discharge is generated from the discharge electrode 5 toward the water film 7, and the gas containing freon rising in the cylindrical body 1 is HF or H in an extremely short time due to the corona discharge.
Decomposes to Cl. A water film 7 is formed on the inner surface of the cylindrical body 1 by the water film forming means 8, and the generated HF or HCl is generated.
Moves to the water film 7 due to Coulomb force, dissolves in the water film 7, and is collected in the container 11 together with water. Since this cylindrical body 1 is made of a synthetic resin such as vinyl chloride, it is not corroded by HF or HCl. Water in container 11 is supplied by pump 1
0 is supplied to the cylindrical body 1 again via the pipe 12 and circulated.

When the concentration of the decomposition product of water in the container 11 is saturated, it may be discharged from the container 11 to the outside, and water may be supplied to the pipe 12 from the outside.

By the way, when the water film 7 is formed on the vinyl chloride cylinder 1, the uniform water film 7 may not be formed due to the water repellency of vinyl chloride.

Therefore, the present inventors tried to form a water film 7 on the inner surface of the vinyl chloride cylinder 1 by using a surfactant.

When the concentration of the surfactant was about 100 ppm, a uniform water film 7 could be formed in the cylinder 1. When the concentration is higher than this, a large amount of bubbles are generated, and therefore, when the concentration is increased, it is preferable to use a low foaming surfactant. As the surfactant, it is preferable to use a fluorine-based surfactant having high chemical resistance, but a commercially available neutral detergent may be used. The components of the neutral detergent are sodium alkyl ether sulfate, fatty acid alkanolamide and alkylamine oxide.

As described above, according to the present embodiment, a water film is formed on the inner surface of a cylindrical body made of a synthetic resin such as vinyl chloride into which fluorocarbon gas is introduced and discharged, and a square wave pulse is formed between the water film and the discharge electrode. Since a voltage is applied and discharged, there is no corrosion of the ground electrode, it is possible to decompose CFCs with high efficiency, and it is not necessary to use a device that absorbs decomposition products, so it is possible to reduce size and cost. it can.

In this embodiment, vinyl chloride is used as the material of the cylinder, but the material is not limited to this, and any other material may be used as long as it is a corrosion resistant material.

[0023]

In summary, according to the present invention, the following excellent effects are exhibited.

It is possible to realize a chlorofluorocarbon gas treatment apparatus which can improve the efficiency of decomposing chlorofluorocarbon gas and can be downsized.

[Brief description of drawings]

FIG. 1 is a schematic view of an embodiment of a fluorocarbon processing apparatus of the present invention.

[Explanation of symbols]

1 cylinder 5 discharge electrodes 6 Square wave pulse voltage power supply 7 water film 8 Water film forming means

─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-5-15737 (JP, A) JP-A-4-322718 (JP, A) JP-A-3-267113 (JP, A) JP-A-52-1 59374 (JP, A) JP-B 45-43 (JP, B1) JP-B 32-13382 (JP, Y1) (58) Fields investigated (Int.Cl. ⁷ , DB name) B01D 53/32 B01D 53 / 34 B03C 3/16

Claims (2)

(57) [Claims] 1. A Freon gas treatment apparatus for decomposing Freon gas by utilizing an electric discharge, wherein a cylinder made of synthetic resin such as vinyl chloride for introducing and discharging Freon gas, a discharge electrode provided in the cylinder, Interface on the inner surface of the cylinder
A flon gas treatment apparatus comprising: a water film forming means for forming a water film containing an activator ; and a square wave pulse voltage power supply for applying a square wave pulse voltage between the water film and the discharge electrode. . 2. Concentration of the above surfactant is about 100ppm
The CFC gas treatment apparatus according to claim 1, wherein