JPS63242903A - Ozonizer - Google Patents

Abstract

PURPOSE:To enable long-term operation by efficient electric discharge in a device having electrodes set both sides of ceramic, by specifying material of the ceramic, thickness of discharges electrode and setting the opposite electrode through a film of a specific material. CONSTITUTION:Discharge electrodes 2, 2... made of oxidation-resistant metal having 0.01-1mm thickness are set on one side of a ceramic plate 1 made of Al2O3 having >=96% purity in such a way that the ends of the discharge electrodes are subjected to pressure welding to the plate 1 and intervals between the neighboring electrodes 2 are channels R for a raw material gas. The metallic opposite electrode 3 is subjected to pressure welding through an insulating metallic oxide film 3a to the other side of the plate 1. An output end of a voltage generating device 4 is connected to at least one of the electrodes 2, 2... and 3 and AC high voltage is impressed between both the electrodes. Consequently, since the plate 1 has about 10-50 dielectric constant, concentration of electric charge and flow of overcurrent are extremely suppressed and further point discharge at the film 3a are relieved. Since the electrodes 2 are thin and show elasticity as metal, the electrodes elastically fix the plate 1 and act as a cushioning material for vibration. Therefore deterioration of the plate 1 is not promoted.

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICATION FIELD 1 The present invention relates to an ozone generator, and more particularly to an ozone generator that ozonizes raw air or oxygen by electric discharge.

``Conventional technology'' Various types of ozone generators have been proposed in the past, and recently ceramics have been developed with excellent dielectric properties, heat resistance,
Focusing on oxidation resistance, the mainstream is to use ceramics in the center and electrodes on both sides.

Problem to be Solved by the Invention 1 However, in an ozone generator using this kind of ceramic soot as an electrolyte, the thickness of the ceramic is about 1 mm, considering the dielectric constant of the ceramic soot, and the tip of the discharge electrode is placed on the ceramic surface. It is possible to place the electrodes in contact with each other, and by narrowing the electrode spacing, it is possible to achieve smaller size and higher efficiency.
This ceramic has poor impact resistance and has the property of exhibiting fatigue and deterioration phenomena due to vibration.

However, if this ceramic is used as a dielectric and electrodes are placed opposite each other at a narrow distance on both sides, the ceramic will deteriorate due to the locally concentrated peak discharge, making it impossible to practically operate the ceramic for long periods of time to generate ozone. It had the following drawback.

Therefore, the present invention has been made to solve the above-mentioned drawbacks.Although electrodes are placed in pressure contact with both sides of ceramics to perform efficient discharge, the shock and vibration caused by discharge are alleviated, and long-time operation is possible. Means for Solving the Problems In accordance with the above object, the structure of the present invention as summarized in the claims described above solves the problems described above. To solve the problem, 96% purity
On one surface of the ceramic plate 1 made of the above alumina, discharge electrodes 2.2.2 made of oxidation-resistant metal with a thickness of 0.01 mm or more and 1 mm or less are pressed at their lower ends to the ceramic plate 1, and the adjacent The discharge electrode 2.2 is erected so that the gap between the discharge electrodes 2 and 2 becomes a flow path R for the raw material gas, and a metal counterpart electrode 3 is pressed onto the other surface of the ceramic plate 1 via an insulating metal oxide film 3a. An output end of an AC high voltage generator 4 is connected to both or either one of the discharge electrodes 2.2.2... and the counterpart electrode 3.
. . . and the mating electrode 3, a technical measure is adopted characterized in that an AC high voltage is applied between the electrode 3 and the mating electrode 3.

r effect J Therefore, in the ozone generator of the present invention, when the ceramic plate 1 is made of alumina with a purity of 96% or more, the dielectric constant is 10 to 5.
0, so even if the tip of the discharge electrode 2゜2.2... and the mating electrode 3 are brought into contact with both sides of the ceramic, concentration of charge and overcurrent flow are significantly suppressed, and in addition, , the insulating metal oxide film 3a alleviates the peak discharge.

Therefore, the AC high voltage generator 4 is used to generate the discharge electrodes 2 and 2.
．． 2... and the mating electrode 3, a mountain-shaped discharge field P shown in FIGS. 4 and 5 is generated at the tip of each discharge electrode 2, and this discharge field P When the applied voltage is increased from a low voltage (3 KV in the embodiment shown in FIG. 4) to a higher voltage (9 KV in the embodiment shown in FIG. 5), its height increases and the area of the discharge field P gradually increases.

In addition, since the discharge electrodes 2, 2, 2, . It acts as a.

Then, the raw material gas flows through the flow path R formed by the discharge electrode 2.degree. 2 where this discharge field P is generated, and the oxygen in the raw material gas is converted into ozone.

Embodiment 1 Next, an embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

In the figure, 1 is a ceramic plate made of alumina with a purity of 96% or more. This ceramic plate 1 has a desired thickness, and in this example, a thin plate with a thickness of 1 mm is used. Although it is theoretically desirable that the thickness be thinner than this in terms of telephone coverage, it is practical to have a thickness of 0.01 mm or more in terms of mechanical strength.

Further, the shape of the ceramic plate 1 may be changed to a thin plate shape and may be made into a conventionally known cylindrical shape.

One surface of the ceramic plate 1 has a thickness of 0.0
Discharge electrodes 2, 2 made of oxidation-resistant metal with a diameter of 1 mm or more and 1 mm or less
．． 2... is pressed at its lower end to the ceramic plate 1,
The discharge electrodes 2.2 are erected so that the gap between adjacent discharge electrodes 2.2 forms a flow path R for the raw material gas.

The discharge electrodes 2, 2.2, etc. are made of oxidation-resistant metal such as titanium, and are either integrally protruded from the substrate portion 2a, or have their base ends buried in the substrate portion 2a (not shown). Similarly, although not shown, the discharge electrodes 2, 2.2
The tips of the... are pressed into contact with one surface of the ceramic plate 1 (as shown in Fig. , reference numeral 5 denotes a closed container wall, and this closed container wall 5 is formed to be somewhat shorter than the discharge electrode 2, or is made of a material having some elasticity.)
In addition, when the ceramic plate 1 is made into a cylindrical shape, the substrate part 2a has a larger diameter than the ceramic cylinder and has discharge electrodes 2.2, 2, . . . protruding radially from its inner surface. It is preferable that the inner diameter of the tip of the ceramic cylinder is slightly smaller than the outer diameter of the ceramic cylinder.

Further, the flow path R is connected to the adjacent discharge type gi2. 2 and
Surrounded by the substrate portion 2a and the ceramic plate 1, raw material gas flows in from the left side in FIG. 2, and flows out after being ozonized from the right side in FIG. In the example shown in FIG. 3, the discharge electrode 2 is formed into a spiral shape instead of a parallel plate shape, and an inlet 2b for raw material gas is formed in the center of the substrate portion 2a, and an outlet is formed in the wall 5 of the sealed container. 5a, and the raw material gas flowing in from the inlet 2b flows between the substrate portion 2a and the ceramic plate 1.
Release masturbation between you and me! , 74 m 2 and passes through a spirally partitioned channel R, where it is ozonized and flows out from the outlet 5a.

A metal counterpart electrode 8i3 is pressure-welded to the other surface of the ceramic plate 1 via an insulating metal oxide film 3a. In the illustrated example, this mating electrode 3 is placed on one side (ceramic plate 1
The contact surface with the metal oxide film 3a is a flat surface made of aluminized insulating metal oxide film 3a with a thickness of several microns to 1 mm, and the other surface is an uneven surface for heat dissipation (in the example, this uneven surface is minute, so it is not shown in the figure). (Although there is no such thing, it is a matter of heat theory that it may be possible to install heat dissipation blades in a row, etc.).

An AC high-voltage generator 4 is connected to both or one of the discharge electrodes 2, 2, 2, and the other electrode 3.
It is the same as the conventional method that the output ends of the discharge electrodes 2, 2, 2, . . .

In the figure, 6 is a water-cooled container having a water inlet 6a at one end and a drain port 6b at the other end so that running water comes into contact with the back surface of the mating electrode 3.

Effect 1 of the invention In the present invention as described above, since the discharge electrodes 2, 2.2... are brought into contact with one surface of the ceramic plate 1, the discharge electrodes 2, 2.2... and the ceramic plate A strong discharge field P is generated near the contact portion with 1, making it possible to provide an ozone generator that efficiently ozoneizes the raw material gas passing through the flow path R. By the way, 4KV is 10KHz.
When a voltage of 100 kW was applied and oxygen was supplied at a rate of 5 J2/min, an ozone concentration of 500 ppm was obtained, and when only the voltage was set to 7 KV under the same conditions, the ozone concentration was 3000 ppm.

The discharge field P generated near the contact portion between the discharge electrodes 2, 2.2, etc. and the ceramic plate 1 impacts the ceramic plate 1 as a peak discharge.
Electrically, the insulating metal oxide film 3a alleviates peak discharge,
Physically, the impact of the peak discharge is alleviated by the elastic force generated by the pressure of the thin discharge electrodes 2, 2, 2, etc., and the electrical and physical relaxation effects are synergistically exerted. Thus, it is possible to provide an ozone generator that can prevent fatigue of the ceramic plate 1 and can operate efficiently for long-term ozone generation.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing one embodiment of the ozone generator of the present invention, FIG. 2 is a perspective view of the same, third is a plan view of another embodiment, and FIG.
5 and 5 are partial cross-sectional views of the discharge site.

Claims (1)

[Claims] On one side of a ceramic plate 1 made of alumina with a purity of 96% or more, discharge electrodes 2, 2, 2, etc. made of oxidation-resistant metal with a thickness of 0.01 mm or more and 1 mm or less are arranged so that their lower ends are Adjacent discharge electrodes 2, 2 are pressure-welded to the ceramic plate 1.
The ceramic plate 1 is provided with an insulating metal oxide film 3a on the other surface.
A metal counterpart electrode 3 is pressed into contact with the discharge electrode 2 through the
, 2, 2, . An ozone generator characterized by applying an alternating current high voltage between.