JPH0550074A - Decomposition apparatus of ozone dissolved in water - Google Patents

Abstract

PURPOSE:To efficiently remove ozone dissolved in water by applying an electric field by using a catalyst having an ozone resolving power as an electrode. CONSTITUTION:Ozone water introduced from an introducing port 1 is thoroughly stirred with a stirring blade 2. The stirring blade 2 and the outer wall 3 are used as electrodes which consist of Co oxide, active carbon, Pt, etc., having an ozone decomposition catalystic power. A power source 4 applies 1.5-10 volts of electric fields between the electrodes and the ozone water is electrolyzed. With this constitution, the activity of the ozone decomposition catalyst is enhanced and, besides, with a reaction between hydrogen and ozone generated by electrolysis of water, the ozone dissolved in water can be efficiently removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dissolved ozone decomposing apparatus for decomposing and removing excess ozone used for deodorization, sterilization, decomposition of organic substances and the like.

[0002]

2. Description of the Related Art Ozone has a strong oxidizing power and is effective in deodorizing, sterilizing and decomposing organic substances.
Currently, it is used for purification of pool water, cleaning of semiconductor chips, purification treatment in water purification plants, sterilization of retort foods, etc., but it is expected to be applied to various fields in the future.
On the other hand, however, excess ozone poses a risk of harming the human body, and in order to effectively utilize ozone, it is essential to develop a catalyst or device that decomposes excess ozone.

At present, with respect to the removal of ozone gas, the development of ozone decomposition catalysts that make up for the drawbacks of the thermal decomposition method and the adsorption decomposition method using activated carbon has progressed considerably, and the ozone gas of high concentration can be decomposed and removed stably for a long time. It has become possible.

On the other hand, the dissolved ozone in water is generally adsorbed and removed by activated carbon, and no catalyst has been used so far.

[0005]

In the case of decomposing dissolved ozone in water by such a conventional ozone removal method, when it is adsorbed and removed by activated carbon, the activated carbon adsorbent becomes a hotbed for bacterial propagation and sterilized with ozone. There was a problem that the sewage water was contaminated with bacteria again.

The present invention solves such problems, and an object of the present invention is to provide a dissolved ozone removing apparatus having a simple structure for decomposing and removing dissolved ozone in water with high efficiency and suppressing bacterial growth. Is.

[0007]

In order to solve the above problems, the present invention provides an ozone water inlet provided in the lower part of an electrically insulating container, and an outlet provided in the upper part of the container. An agitation blade and an outer wall provided inside the container, and a power source disposed outside the container and electrically connected to the agitation blade and the outer wall, and a voltage is applied using the agitation blade and the outer wall as electrodes. However, ozone water is introduced from the inlet, and ozone is electrolyzed and discharged from the outlet.

Further, the stirring blade and the outer wall are constituted by an ozone decomposition catalyst.

[0009]

According to this structure, the dissolved ozone can be almost completely decomposed by chemically decomposing the dissolved ozone by the ozone decomposing catalyst and electrolyzing it by using the stirring blade and the outer wall as electrodes. In addition, bacteria are not propagated to contaminate the deozoned water, and sanitary and safe water can be supplied.

Further, according to the present invention, by applying a voltage to the ozone decomposing catalyst, the ozone decomposing activity of the catalyst is improved and the hydrogen produced by electrolysis of water also decomposes the dissolved ozone. Will be decomposed and removed with high efficiency.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An ozone decomposing apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the construction of an apparatus for decomposing dissolved ozone in water. As shown in FIG. 1, a container 7 is provided with an ozone water inlet 1 at the bottom, treated water outlet 6 at the top, and is composed of a propeller-shaped stirring blade 2, an outer wall 3, and a power source 4. The stirring blade 2 and the outer wall 3 also serve as electrodes, both of which are composed of an ozone decomposition catalyst (Co-based oxide, Pt activated carbon, etc.), and the power source 4 supplies 1.5 to 10 V, preferably 6 to 8 V.
Is being applied.

Specific examples of the present invention will be described below. (Example 1) In the water-dissolved ozone decomposing apparatus configured as described above, L was used as an electrode material for the stirring blade 2 and the outer wall 3.
a _0.6 Sr _0.4 Co _0.9 Fe _0.1 O _3-8 was used as the main component, and the applied voltage was 8 V. Ozone water with a concentration of 5 mg / l was passed through the device at a flow rate of 1 l / min and the discharge port was used. The time-dependent change of the dissolved ozone concentration in 6 was measured. The results are shown in (Table 1).

(Example 2) Ozone water was passed under the same conditions as in Example 1 except that no electric field was applied to the electrodes, and the change with time of the dissolved ozone concentration at the outlet 6 was measured. The results are shown in (Table 1).

(Comparative Example 1) The electrode material forming the stirring blade 2 and the outer wall 3 was changed to stainless steel having no ozone decomposition catalytic ability, water was passed under the same conditions as in Example 1 with an applied voltage of 8 V, and then discharged. The results of measuring the dissolved ozone concentration at the outlet 6 are shown in (Table 1).

Comparative Example 2 Water was passed under the same conditions as in Comparative Example 1 without applying an electric field, and the concentration of dissolved ozone at the outlet 6 was measured. The results are shown in (Table 1).

[0017]

[Table 1]

As shown in (Table 1), the conditions of Example 1 decompose ozone most effectively, and the residual ozone amount increases in the order of Example 2, Comparative Example 1 and Comparative Example 2 below.

In the present embodiment, the Co oxide was explained as the ozone decomposition catalyst, but the same effect can be obtained by using an ozone decomposition catalyst such as Pt or activated carbon.

[0020]

As is apparent from the above description of the embodiments, according to the present invention, the activity of the ozone decomposition catalyst is improved by passing water while applying an electric field to the electrode composed of the ozone decomposition catalyst. However, it is possible to decompose dissolved ozone almost safely from immediately after passing water for a long time.

[Brief description of drawings]

FIG. 1 is a block diagram of an apparatus for decomposing dissolved ozone in water according to the present invention.

[Explanation of symbols]

 1 inlet 2 stirring blade 3 outer wall 4 power supply 5 lead wire 6 outlet 7 container

Claims (2)

[Claims] 1. An ozone water inlet provided in a lower portion of an electrically insulating container, and an outlet provided in an upper portion of the container,
An agitation blade and an outer wall provided inside the container, and a power source disposed outside the container and electrically connected to the agitation blade and the outer wall, and a voltage is applied using the agitation blade and the outer wall as electrodes. Meanwhile, an apparatus for decomposing dissolved ozone in water, which introduces ozone water from the inlet, electrolyzes the ozone water and discharges it from the outlet. 2. The water-dissolved ozone decomposing apparatus according to claim 1, wherein the stirring blade and the outer wall are constituted by an ozone decomposing catalyst.