JPH01262994A - Water treatment apparatus - Google Patents

Abstract

PURPOSE:To reduce the load of an ozone reaction tank, by providing a submerged trough, which discharges a surface floating substance along with water, to the upper part of an ozone reaction tank for performing the gas-liquid contact of water to be treated and ozone-containing gas. CONSTITUTION:In a water treatment apparatus using ozone, water to be treated is introduced into an ozone reaction tank 1 from the upper part or side wall part thereof and ozone-containing gas is injected in the tank 1 from the lower part thereof while ozone treated water is allowed to flow out from the lower part or lower side wall part 3 of the tank 1. Further, the substance floating on the surface of the water is allowed to flow out from a trough 7 along with water. When water to be treated is brought into the gas-liquid contact with the ozone-containing gas from an air diffusing pipe 5, float separation such as the precipitation of a solid and microfloc is generated. When valves 9, 13 are opened, the surface layer part of the water in the tank 1 flows to the trough 7 to be discharged. As mentioned above, the floating accumulated substance is periodically discharged and the load of the ozone reaction tank is reduced and the unnecessary increase of the dissolved org. substance in water after ozone treatment is prevented.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial usage Wf) The present invention relates to a water treatment device for purifying contaminated water.

(Conventional technology) Traditionally, ozone's oxidizing power has been used to sterilize water using water treatment technology.

It has been used for decolorization, deodorization, and oxidation of organic substances.

Ozone is produced by electrical discharge against air or oxygen and is obtained as an ozone-containing gas. Water treatment uses aeration pipes, injectors, packed towers, etc. to bring gas and liquid into contact with the water to be treated. Gas-liquid contact using air diffusers and injectors introduces fine ozone-containing gas from the bottom of the tank into a continuous layer of water to be treated. Purify by oxidation.

Upon reaching the water surface, the bubbles are broken and the unreacted ozone-containing gas is rendered harmless outside the ozone reactor and released into the atmosphere. On the other hand, the water to be treated undergoes ozone oxidation and is then discharged from the bottom or side of the ozone reaction tank.

Because of its strong oxidizing power, ozone treatment has begun to be used for purifying tap water or treated sewage water.

(Problems to be solved by the invention) However, when ozone treatment is performed for a long time in a conventional gas-liquid contact tank, several problems have arisen. If there are pollutants in the water to be treated that enters the gas-liquid contact tank,
Fine bubbles of ozone-containing gas float to the upper water surface and form a scum. Further, dissolved substances undergo ozone oxidation, and many deposits of grease-like substances are observed.

These substances remain near the water surface as floating objects.

It will stick to the walls of the tank and make a mess. Further, due to contact with ozone, ozone oxidation products of organic matter are generated and dissolved in water, albeit in small amounts, and this becomes a burden on water treatment. For these reasons, it is better to remove floating objects from the inside of the pot at an early stage. However, the upper part of the tank was filled with gas containing unreacted ozone, making it difficult to observe and discharge it.

The present invention proposes a water treatment device that solves the drawbacks of conventional methods using a simple device and operation.

[Structure of the Invention] (Means for Solving the Problems) The present invention includes a gutter installed under the water surface in the upper part of the ozone reaction tank in which ozone-containing gas is brought into gas-liquid contact with the water to be treated so as to discharge the surface-floating substances together with the water. This is a water treatment device characterized by:

(effect) The present invention floats and accumulates on the water surface above the ozone reaction tank.

To reduce the load on the ozone reaction tank and to prevent unnecessary increases in dissolved organic matter in the ozonated water, by periodically discharging the substances that cause the ozone treatment.

(Example) An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention, in which a rectangular ozone reaction tank 1 has a treated water population 2 and a treated water outlet 3, and an ozone-containing gas introduction pipe is provided at the bottom of the ozone reaction tank 1. After gas-liquid contact, the bubbles are separated at the water surface and are led as a gas containing unreacted ozone from an exhaust gas pipe 6 to an ozone decomposition device (not shown). A gutter 7 for discharging water from the surface is provided below the water surface, and a water guide pipe 8 and a valve 9 are attached to a part of the gutter 7, and the discharged water is led to a drain tank 10 and drained through a drain pipe 11.

The drainage tank is provided with an air venting pipe 12, which is connected via a valve 13 to an exhaust gas exhaust pipe 6 for unreacted ozone-containing gas.

In the water treatment device configured as above.

In the ozone reaction tank 1, the treated water introduced from the treated water population 2 is mixed with fine bubbles of ozone-containing gas generated from the aeration pipe 5 connected to the ozone-containing gas introduction pipe 4 provided at the bottom. Upon contact with the liquid, precipitation of solid matter, micro flocs, or flotation separation of suspended matter by air bubbles occurs, and over a long period of time, floating substances are generated and accumulated on the water surface. In the present invention, the degree of generation of floating substances differs depending on the water to be treated, but by opening the valves 9 and 13 once a week, for example, the surface layer of the water flows in the direction of the gutter 7, leaving floating substances unreacted with water. Valve 9 with ozone-containing gas. The water can be discharged through a water conduit 8 into a drainage tank 10 and can be discharged through a drainage pipe 11. By opening and closing valves 9 and 13.

Since unnecessary substances can be discharged to the upper part of the ozone reaction tank 1, the upper part of the ozone reaction tank can be kept clean.
It does not increase soluble ozone oxidation products in the treated water.

Another embodiment of the invention is shown in FIG. This example is an example of a multi-stage reaction tank. The same parts as in FIG. 1 will be described with the same numbers. The ozone reaction tank 1 is divided into three tanks, and the water to be treated is introduced from the inlet 2 and undergoes gas-liquid contact in part A by reusing unreacted ozone-containing gas. The unreacted ozone-containing gas is discharged from part B, and is discharged from exhaust gas pipe 1.
4. The air is pressurized by the blower 15 and injected into the water as fine bubbles through the air diffuser 5a. The treated water moves from the lower part of part A to the next part B, and comes into contact with the ozone-containing gas introduced through the ozone-containing gas introduction pipe 4 and the aeration pipe 5. The treated water is sufficiently oxidized by ozone and flows to the 0 part, and the treated water is sent to the treated water outlet 3.
more excreted. The unreacted ozone-containing gas in section B is discharged from the exhaust gas pipe 14. The air is sent to section A by the blower 15. The exhaust gas in section A is led to an ozone decomposition device (not shown) through an exhaust gas exhaust pipe 6.

Particularly in part A of the ozone reaction tank 1, floating separation of suspended matter due to air bubbles and deposition of precipitated substances, particularly grease-like substances, occur frequently due to the ozone reaction. In the present invention, a gutter 7 is attached below the water surface on the wall surface of part A, and a water conduit 8 with a valve 9 is provided to drain the drain tank 10.
is leading to. It goes without saying that the gutter 7 may be provided on four sides of the water surface in the upper part of the ozone reaction tank 1, or that the gutter 7 may be placed in the center, separated from the wall.

[Effect of the invention] It is known that ozone generates grease-like substances or micro flocs through partial oxidation of dissolved substances.On the other hand, ozone oxidation of suspended substances causes the formation of soluble ozone oxidation products. generation is also known. By periodically discharging the floating substances that are generated and accumulated on the water surface above the ozone reactor, water treatment can be performed safely.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a water treatment device showing an embodiment of the present invention;
FIG. 2 is a configuration diagram showing an embodiment of the pond. 1... Ozone reaction tank 2... Treated water inlet 3... Treated water outlet 4... Ozone building body introduction pipe 5.5'...
... Diffuser pipe 6.14 ... Exhaust gas pipe 7 ... Gutter 8 ... Water pipe 9 ... Valve 10 ... Drain tank 11... Drain pipe 12... Air venting pipe 13... Patent attorney Noriyuki Chika Yudo Sanno - Figure 1 Figure 2

Claims (1)

[Claims] An inlet pipe that introduces the water to be treated from the top or side, a diffuser pipe that injects ozone-containing gas from the bottom, a treated water outlet pipe that performs ozone treatment and discharges the ozonated water from the bottom or side, and gas-liquid. A water treatment device comprising a gutter that drains floating objects on the water surface that are separated together with the water, and a drainage pipe and a valve that drains the effluent from the gutter.