JPH01215395A - Water treating device - Google Patents

Abstract

PURPOSE:To prevent sticking and growth of slime, etc., by disposing a filter column which eliminates a water stagnating part in the bottom at the time of water draining to the water treating device in order to sterilize the entire surface of the lower part of a sand filter column and the piping to an ozone reaction column. CONSTITUTION:The water treating device is constituted of the main sections including the sand filter column 1, the ozone reaction column 2 and an active carbon column 3. The raw water which is contaminated by org. matter, turbid matter, etc., enters the sand filter column 1 from an upper conduit 4 thereof and passes though a sand filter bed 5. The water removed of the turbid matter passes through a conduit 6 from the lower part and is subjected to ozone oxidation in the ozone reaction column 2. An ozonizing gas is injected into the water from an air diffusion pipe 7 and the unreacted ozonizing gas is discharged from a gas discharge pipe 8. The water subjected to ozone oxidation is introduced from a conduit 9 in the lower part of the ozone reaction column to the upper part of the active carbon column 3 and passes through the active carbon layer 10. The activated water is obtd. from the piping 11 in the lower part of the column.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) 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.

However, when water containing a large amount of organic matter is subjected to ozone treatment, oxidation products such as aldehydes, ketones, and carboxylic acids are produced, making the water unsafe for drinking.

In recent years, water purification methods developed mainly in Europe allow microorganisms to grow on the activated carbon surface while water after ozonation is passed through an activated carbon layer, purifying the ozone oxidation products as food. In this method, unprocessable ammonia is purified by microbial metabolism, extending the lifespan of activated carbon. Recently, this water treatment method has been attracting attention due to the pollution of water sources in Japan, especially river water.

(Problems to be Solved by the Invention) However, the chemicals that have been widely used in the purification of drinking water, namely chlorine, which prevents microbial damage during the purification process, are only used as residual chlorine after purification. The sand filter tower before ozonation is operated without being sterilized.

Due to long-term operation, microorganisms and small animals grow in the sand filter tower. The growth of attached organisms on the floor that is regularly backwashed is kept at a constant level, but at the bottom of the sand filter tower.

In the piping to the ozone reaction tower, slime-like lumps that have grown on the walls are peeled off and flow into the ozone reaction tower and activated carbon tower.In particular, the film-like peeled off material is repeatedly sent to the upper part as bubbles rise in the ozone reaction tower. It is difficult to be transported and discharged from the tower. During this period, it comes into contact with ozone for a long time, consumes a large amount of ozone, and generates oxidized water-soluble organic substances. There was a problem in that even if the film-like peeled material entered the activated carbon tower, it was difficult to be discharged during backwashing, and it also accelerated the decrease in the flow rate of the activated carbon tower.

The present invention provides a water treatment device that solves the drawbacks of conventional methods with simple equipment and operation.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides water containing organic matter, ammonia, etc.
In equipment that purifies water through ozone treatment and activated carbon, after periodically completely draining the water, ozonated gas is passed through the lower part of the sand filter tower and the inner surface of the piping to the ozone reaction tower to sterilize microorganisms and remove slime. This is a water treatment device featuring:

(Function) The present invention regularly passes ozonized gas through the pipes between the lower part of the sand filter tower and the ozone reaction tower to prevent the growth of slime and other adhesion and eliminate the growth of film-like exfoliated substances.

(Example) An example of the present invention will be explained with reference to the drawings. The water treatment apparatus shown in FIG. 1 is composed of the main parts of a sand filter tower 1, an ozone reaction tower 2, and an activated carbon tower 3.

Raw water contaminated with organic matter and turbidity enters the upper conduit 4 of the sand filter tower 1, passes through the sand filter 5, removes the turbidity, and passes through the lower part through the conduit 6 to the ozone reaction tower 2. undergoes ozone oxidation. The ozonized gas is injected into the water through the diffuser pipe 7 at the bottom of the ozone reaction tower 2, and the unreacted ozonized gas is discharged from the exhaust gas pipe 8. Water that has undergone ozone oxidation is introduced into the upper part of the activated carbon tower 3 from a conduit 9 at the bottom of the ozone reaction tower, passes through an activated carbon layer 10, and purified water is obtained from a pipe 11 at the bottom of the tower.

When used for a long period of time, the amount of suspended solids removed by the sand filter passing tower 1 increases, and the resistance of the sand filter method 5 increases. Backwash filtration method 5,
The suspended solids are discharged from the tower through the drainage pipe 13, the sand filter is left still, and the raw water is passed through.

Similarly, when the activated carbon tower 3 is used for a long time, the oxidation products in the ozonated water are metabolized by the microorganisms grown on the activated carbon surface, and the amount of microorganisms increases and the resistance of the activated carbon layer 10 increases. Add backwash water and activate carbon layer 1
The microorganisms attached to the surface of the activated carbon are peeled off and discharged to the outside of the tower from the piping 15 as backwash wastewater, and the activated carbon layer 10 is allowed to stand still again, and ozonated water is passed through.

This water purification method makes maximum use of the effects of microorganisms on the surface of activated carbon, so it does not use chlorine, which has strong residual properties. For this reason,
Microorganisms and small animals grow on the inside of the device that passes water rich in organic matter before it comes into contact with ozone. In particular, the slime that has grown on the lower wall of the sand filter tower 1 and the inner surface of the conduit 6 becomes a film-like mass and peels off. This will cause damage to the activated carbon tower 3.

In the present invention, when draining water to the lower part of the sand filter tower 1, after the water is completely drained from the drain valve A which is sloped so that water does not accumulate at the bottom, ozonized gas is periodically introduced into the sand filter tower 1. By sterilizing the inner surface of the conduit 6 at the bottom of the ozone reactor, it is possible to prevent microorganisms growing on the wall surface and the formation of film-like deposits. Therefore, when draining water from the drain valve A, if the same amount as the flow rate of the ozonized gas injected into the ozone reaction tower 2 from the aeration pipe 7 is used, the exhausted ozone can be introduced as is. Can be done. Further, the ozonized gas can be directly introduced from valve B using the distribution pipe 16 while remaining at a high concentration.

If water remains at the bottom, the microbial sterilization effect on the surface of the tower and pipes below the water surface will be incomplete, and in the long run, film-like exfoliation will occur. It is important to sterilize at the same time.

Sterilization with ozonized gas takes about 10 minutes, and unreacted ozonized gas after use is discharged automatically through piping 6 through piping 8 when water is passed through sand filter tower 6.

These operations are particularly effective if performed before backwashing the sand filter device 1.

〔Effect of the invention〕

Ozone is known to sterilize and inactivate microorganisms and viruses in water.
It has also been confirmed that it can also sterilize and exfoliate slime. After sloping the bottom and draining the water completely, introducing ozonized gas periodically to the bottom of the sand filter tower and the inside of the piping can kill the microorganisms growing on the surface and prevent them from growing into film-like flakes that can cause problems. Water treatment can be carried out with peace of mind.

[Brief explanation of the drawing]

The drawing is a configuration diagram of a water treatment device showing an embodiment of the present invention. 1... Sand filter tower 2... Ozone reaction tower 3.
...Activated carbon tower 16...Distribution pipe A...Drain valve B...Valent agent Patent attorney Noriyuki Chika Yudo Yamashita -

Claims (1)

[Claims] Water that has passed through the sand filtration tower is purified by an ozone reaction tower that brings ozonized gas into gas-liquid contact and an activated carbon tower that passes the ozonated water. This water treatment equipment is equipped with a sand filtration tower that eliminates water retention at the bottom during drainage, in order to sterilize the interior and all surfaces using ozonized gas.