JPS60251104A - Silent discharge ozone generator - Google Patents

Abstract

PURPOSE:To provide the titled ozone generator capable of preventing dielectric electrodes from rust generation by constructing metallic tubes of the dielectric electrodes of ferritic stainless steel or martensitic stainless steel having a Cr content regulated to above a specified value. CONSTITUTION:The silent discharge ozone generator is constituted with a high voltage side electrode 2, an earthed side electrode 3, and a discharge space 5 provided between both electrodes. At least one of the electrode 3 and 4 is covered by a dielectric electrode 4a constituting ferritic stainless steel or martensitic stainless steel having >=12% Cr content and 120X10<-7>mm./mm. deg.C coefft. of linear expansion. Specific examples for said material are SUS430, SUS403, etc. Since the metallic material of the dielectric electrode is scarcely rusted and the coefft. of linear expansion is close to the coefft. of linear expansion of dielectric glass, rust generation due to cooling water and corrosion of the electrode tube are prevented, and the life of ion exchange resin is prolonged. The maintenance is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a non-discharge type ossin generator that prevents the occurrence of rust.

[Prior art]

In ozonizers that utilize non-discharge, the first
As shown in the figure, a gap is provided between the high voltage and the ground connection via a dielectric, and a part of the oxygen in the supplied raw material gas is converted into ozone by generating an angular discharge. That is, in Fig. 1, (1) is the exchange power source, (21 is the high voltage 1IIl' pole, (3) is the ground side electrode, (4) is the dielectric electrode, (5) is the discharge space, (6) indicates the high-voltage and grounding wires, and in this type of ozone generator,
It is well known that the electrical characteristics of the lightning power applied are expressed by the following equation:

(2) In the equation, W is the discharge power, f#- is the frequency of the applied source, Cg is the electric current of the dielectric electrode, Ca is the electric current of the discharge space, S is the area of the discharge electrode, and v8°Ve is The spark voltage and extinguishing voltage are respectively shown, and Em indicates the peak value of the applied voltage. In order to obtain a predetermined value of the discharge force W according to the formula (2), L Cg+ sI Vllll Yet CatEm must be appropriately selected. On the other hand, the relationship between the discharge power W and the amount of ozone generated in the ozone generator is shown in the discharge space (5).
It depends on the gas content, pressure, temperature, moisture content, discharge space length, etc. In a practical ozone generator, there is a proportional relationship between the discharge power W and the amount of ozone generated, as shown in FIG.

By the way, in conventional ozone generators, borosilicate glass, lead-containing glass, mica, or the like is generally used as the material for the dielectric electrode (4) forming the discharge electrode. In this case, s'*, the dielectric constant of the body electrode (4) is about 5 to 8. Note that the discharge area S has a significant influence on the relationship between the discharge power and the amount of ozone produced as a discharge power density number, and is therefore appropriately designed. In addition, the discharge space length is generally selected to be about 1 to 2 cm, taking into account the electrode manufacturing technology, since it affects the discharge state and the temperature of the discharge part. Therefore, once the gas pressure, temperature, etc. are determined, The spark voltage Vs and the extinguishing voltage Ve are determined. Therefore, the discharge power wB = Generally, the power supply frequency f or the peak value Em of the discharge voltage is used as a variable value for controlling the ozone generator. Tables 1 and 2 show the conventional The general characteristics of ozone generators that have been put into practical use are shown below.

Table 1 Electrical characteristic specifications for conventional type commercial frequency ozonizer Table 2 Electrical characteristic specifications for conventional type high frequency ozonizer It was formed by applying glass powder using a method and firing it.

However, during actual operation, rust occurs on the dielectric electrode (4) due to ion-exchanged water being used to cool the discharge tube.As a result, the properties of the ion-exchange resin deteriorate quickly, and if these properties deteriorate significantly. There were drawbacks such as the need to replace the n1M body*pole (4).

[Overview of the invention]

The present invention has been made to solve all of the above-mentioned drawbacks, and in order to obtain a silent discharge type ozone generator that prevents rust, chromium (CCr) is added to the metal tube material of the dielectric electrode.
The present invention provides a silent discharge type ozone generator to which a ferritic stainless steel material and a martensitic stainless steel material with a content of 12% or more are applied.

[Embodiments of the invention]

FIGS. 3(a) and 3(b) are perspective views of the principle of an embodiment of the present invention. (21tj: High voltage side electrode, (3) is ground 1
Ill! pole, (5) is the high voltage side electrode (2) and ground 1l
li ′ItV (31 is a discharge space provided between The discharge space (5) is equipped with a supply element (not shown) that supplies the raw material gas and converts the oxygen in the raw material gas into ozone through discharge. (4a) Dielectric electrode, ?#b1! Piezo electrode (2) or ground side electrode (
At least one of 3) is in contact with a dielectric electrode (4a). Figure 6 (&) shows the case where the dielectric electrode (4a) connects the ground side electrode [3], and Figure 6 (b)
shows the case where the vj dielectric electrode 4a) is in contact with the high voltage side electrode (2).

The metal tube material of the dielectric electrode (4a) in the present invention has a chromium content of 12 or more and a linear expansion coefficient of 120 x 1.
4: It is composed of a ferritic stainless steel material and a martensitic stainless steel material (0°C to 100°C). As such metal pipe material, for example, 5U
S430 material, 5US405 material, and 5US403 material can be drilled.

Dielectric electrode (4a) conventionally used in ozone generators
) materials include barium oxide, boron oxide, zirconium silicate oxide, aluminum oxide, titanium oxide, cobalt oxide materials, etc., and the actually measured linear expansion coefficient is 91 x 1
It was 0-'-/m·℃. Therefore, dielectric electrode (4h)
The coefficient of linear expansion of the material is, for example, 5US43 according to the present invention.
The coefficient of linear expansion is slightly smaller than that of stainless steel tube, which is 104×10-'C.℃.

Maro■ However, SUS, which is an austenitic stainless steel,
Linear expansion coefficient of 304 steel pipe 180 x 10-'-,-・℃
There is a big difference compared to

When manufacturing the dielectric electrode (4) shown in Figure 1, if SUS 304 material is used for the metal tube material of the dielectric electrode (4), cracks may occur at the ends of the dielectric electrode (4). , it is not possible to form a good discharge tube. However, when the SUS 430 material according to the present invention was used as the metal tube material of the dielectric electrode (4a) shown in Fig. 6, no cracks occurred and the result was good.In general, the martensitic stainless steel material according to the present invention, Ferritic stainless steel materials have a smaller linear expansion coefficient than austenitic stainless steel materials, and when conventionally used dielectric glass is coated and fired, the internal stress generated due to the difference in linear expansion coefficients is reduced.

Furthermore, the dielectric electrode (
Rust inside the metal tube in 4a) can be removed by using the conventional steel pipe dielectric electrode (4a).
), coloring of the cooling water was observed after 2 to 6 weeks of use. However, SUS 4 according to the present invention
In the case of the dielectric electrode (4a) made of No. 30, no coloring of the cooling water was observed even after one year or more, and no rust was generated, which was extremely good.

Note that FIG. 4 is a front view showing an embodiment of the present invention, in which the high voltage side electrode (2), the dielectric electrode (4b), and the ground side electrode (3) are configured in a hollow cylindrical shape.

In the above description, a dielectric electrode using 5US430 material has been described, but the water valve FJA is not limited to this, and may be made of other martensitic stainless steel materials or ferritic stainless steel materials.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, a material that is resistant to rust and has a coefficient of linear expansion close to that of dielectric glass is used as the metal material of the dielectric electrode, so that rust on the metal tube caused by cooling water is prevented. Furthermore, by prolonging the life of the ion exchange resin and preventing corrosion of the electrode tube, there are remarkable effects such as easy maintenance, low cost, and high reliability.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram showing an example of a conventional silent discharge type ozone generator, Fig. 2 is a diagram showing the relationship between discharge power and the ozone generation lid, and Fig. 3 (a)) (h), FIG. 4 is a schematic diagram showing an embodiment of the present invention, and FIG. 4 is a perspective view of the embodiment of the present invention. ill...AC power supply, (2)...high voltage (ti11
Electrode, (3)...Ground side electrode, (4a) - (4b
)...Dielectric electrode, (5)...Discharge space (6).
...High-voltage and grounding power lines The same symbols in each prisoner shall indicate the same or equivalent parts. Agent: Patent Attorney Sanro Kimura Figure 1 Figure 2 Figure 3 Figure 4 Procedural amendment (voluntary) December 25, 1980 Mr. Commissioner of the Japan Patent Office, 1. Indication of the incident Patent application No. 59-107580 2,
Name of the invention: Silent discharge ozone generator 3, Person making the amendment 4, Agent 2 Miscellaneous, Subject of amendment 6, Contents of amendment (1) The "Claims" of the specification are amended as shown in the attached sheet. . (2) [Dielectric electrode (4)] in the 8th line from the bottom of the table on page 5 of the specification indicates that ``The ion exchange resin must be replaced, and the dielectric electrode (4) has become extremely rusty.''"Ba," he corrected. (3) Linear expansion coefficient is 1 on page 7, line 2 to line 3 of the specification.
20X 10-”I1m/work°℃(θ℃～100℃)1
Delete. (4) "U zirconium silicate oxide" on page 7, line 10 of the specification is corrected to "gayric oxide, zirconium acid." (5) “Cobalt oxide material” on page 7, line 11 of the specification is “
"Glass made from cobalt oxide raw material". The above appended claims (amendment) [(1) Applying a high voltage between the ground side electrode and the high voltage side electrode, and the ground side electrode and the high voltage side electrode to generate a discharge in the discharge space between the electrodes. a supply element that supplies the raw material gas to the discharge space and ozonates oxygen in the raw material gas by discharge;
and a dielectric electrode covering at least one of the ground side electrode and the high voltage side electrode, and the metal tube material constituting the dielectric electrode is made of a ferritic stainless steel material and a martensitic stainless steel material with a chromium content of 12 p. A silent discharge type ozone generator comprising the following features. (2) An indigo silent discharge type ozone generator according to claim 11, characterized in that the metal tube material of the dielectric electrode is made of 5US430 material. (3) A silent discharge type sub-sink generating device of claim 1, characterized in that the metal tube material of the dielectric electrode is made of 5US405 material.

Claims (1)

[Claims] A power supply that applies a high voltage between the IF+ ground side electrode and the high voltage side electrode, the #ground 1u11 electrode and the high voltage 11m electrode to cause a discharge in the discharge space between the electrodes, and a source material in the discharge space. A supply element that supplies gas to ozonize oxygen in the raw material gas for discharge, and a dielectric electrode that is in contact with at least one of the ground 1lIIiII electrode and the high voltage 111 electrode, and constitutes the dielectric electrode. Metal pipe material with a chromium content of 1
At 2% or more, the linear expansion coefficient is 120' x 10-' −/
A silent discharge type ozone generator characterized by being constructed of ferritic stainless steel material and martensitic stainless steel material having a temperature of 1°C. (2) The silent discharge type ozone generator according to claim 111, wherein the metal tube material of the dielectric electrode is made of 5US430 material. Claim No.
The silent discharge ozone generator according to item 11. (4) Claim 111, characterized in that the metal tube material of the dielectric II pole is made of 5US403 material.
Silent discharge type ozone generator described in 2.