JPH08252433A - Polluted water treatment device - Google Patents

Abstract

PURPOSE: To efficiently obtain clear water by a combination of a filter device using a floating filter medium and a biological treatment membrane, by mounting the floating filter medium in a treatment tank, and further, a solid-liquid separation membrane in the floating filter medium layer or on the downstream side of a polluted water to be treated. CONSTITUTION: A floating filter medium 2 is mounted in a treatment tank 1, and a solid-liquid separation membrane 3 is provided in the floating filter medium 2 layer or on the downstream side of a polluted water to be treated. In addition, an untreated water feed pipe 4 is opened at the lower part of the treatment tank 1 and the solid-liquid separation membrane 3 of a cylindrical form is suspended from the top of the treatment tank 1 to extract a treated water. Further, air diffusion pipes 6 are arranged respectively in the floating filter medium 2 layer and an untreated water chamber 1a, and at the same time, the opening of a cleaning water pipe 7 for the filter medium is provided to the lateral wall of the treatment tank 1 through the floating filter medium 2 layer. In addition, the opening of a drain pipe 8 for backward washing of the floating filter medium 2 is provided at the bottom of the treatment tank 1. Thus, solid matter is captured and removed during the ascent of the polluted water through the floating filter medium 2 layer. At the same time, organic matter therein is decomposed by microbes in the filter media, and the treated water containing a reduced amount of pollutants is subjected to a separation treatment using the solid-liquid separation membrane.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an apparatus for treating wastewater such as sewage.

[0002]

2. Description of the Related Art A biological treatment apparatus using a floating filter medium is known, and a membrane separation apparatus using a solid-liquid separation membrane such as a microfiltration membrane, an ultrafiltration membrane or a reverse osmosis membrane is also known.

[0003]

However, in the above-mentioned biological treatment apparatus, although the quality of treated water is improved in a shorter time than the conventional biological treatment method, it is still not sufficient, and the quality of the discharged or reused water is not improved. Therefore, when a good quality of treated water is required, it is necessary to separately provide a filtration device and a coagulating sedimentation device at the subsequent stage.

Further, in the above-mentioned biological treatment apparatus, although the treatment capacity can be enhanced by increasing the amount of microorganisms in the floating filter medium layer, when the amount of microorganisms becomes excessive, it leaks to the treated water side and must be prevented. Was difficult.

Further, in the above-mentioned membrane separation device, the removal of non-solid substances such as soluble organic substances is insufficient, so that it is necessary to further treat the treated water in the membrane separation device.

Further, in the above-mentioned membrane separation device, the concentration near the surface of the solid-liquid separation membrane becomes thicker, solids are stacked, etc., and the water flow rate decreases in a short time. A so-called cross-flow method that produces a high-speed flow at a right angle must be adopted, and extra energy is required in addition to the energy for membrane separation.

[0007]

SUMMARY OF THE INVENTION The present invention is capable of solving the above-mentioned problems, and the gist of the present invention is to install a floating filter medium in a processing tank and to remove the floating filter medium in the floating filter layer. Alternatively, a solid-liquid separation membrane is provided on the lower flow side of the treated water, a raw water supply port is provided at the lower part of the treatment tank, and a treated water outlet is provided at the upper part of the treatment tank.

[0008]

Since the apparatus according to the present invention is configured as described above, while the wastewater rises in the floating filter medium layer, its contaminants (solid matter) are captured and removed, and the wastewater in the filter medium layer is removed. Organic matter is decomposed by microorganisms. Then, when this sewage passes through the filter medium layer, as a result of capturing solids,
Leakage of solids into filtered water is suppressed. At the same time, it becomes possible to operate while maintaining the amount of microorganisms in the filter medium layer at a high concentration, and the processing capacity can be improved.

Next, the treated water whose polluted amount is reduced in this way is separated by the solid-liquid separation membrane, and the treated water treated in these two stages is removed from both the solid matter and the dissolved matter. It is clean water that can be reused without problems.

In the above-mentioned processing operation, if a diffusing pipe is installed in the floating filter medium layer for aeration, microorganisms in the filter medium layer can be activated and proliferated, and the solid-liquid separation membrane By vibrating the surface water or the floating filter medium, it is possible to prevent the solids from being stacked on the solid-liquid separation membrane or from excessively increasing the concentration. That is, the pollution load on the solid-liquid separation membrane can be reduced, and the surface of the solid-liquid separation membrane can be cleaned, so that the amount of water flow and the life of water passage can be improved and the device capability can be improved. Hereinafter, the present invention will be specifically described with reference to the drawings.

[0011]

EXAMPLE FIG. 1 shows an example in which a flotation filter 2 and a solid-liquid separation membrane 3 are loaded in a treatment tank 1, a raw water supply pipe 4 is opened in the lower portion of the treatment tank 1, and an upper portion of the treatment tank 1 is opened. A cylindrical solid-liquid separation membrane 3 is hung from there to take out the treated water. Further, an air diffuser 6 is installed in the floating filter medium layer and in the raw water chamber 1a, and a washing water pipe 7 for filter medium is opened in the floating filter medium layer on the side wall of the treatment tank 1.

A drain pipe 8 for backwashing water of the floating filter medium 2 is opened at the bottom of the treatment tank 1, and the drain pipe 8 is raised in a U-shape. An exhaust hole is provided in the ceiling wall of the processing tank 1, and an exhaust pipe 9 thereof is raised to enable constant pressure filtration of the water head H. In FIG. 1, reference numeral 10
Is a treated water extraction pipe, and 11 is a screen for locking the floating filter material 2.

In the treatment apparatus constructed as described above, the raw water supplied from the lower portion of the treatment tank 1 is trapped in the impurities (solid matter) while rising in the layer of the floating filter medium 2 and is floated. When the filter medium 2 is contacted with it, microorganisms on the surface decompose organic compounds contained therein.

Then, the inside of the processing tank 1 is further raised, and even the fine solid matter is separated by the solid-liquid separation membrane 3, and the clear filtrate can be taken out from the take-out pipe 10. During this period, the microorganisms on the surface of the floating filter medium 2 can be activated by ventilating the inside of the treatment tank 1 through the air diffuser 6. Then, this ventilation is discharged from the exhaust pipe 9 to the outside of the tank.

When the amount of water passing through the solid-liquid separation membrane 3 (treated water) is reduced by such an operation, the solid-liquid separation membrane 3 is washed and regenerated by supplying air from the backwash air pipe 5. You can At this time, the backwash air is taken out of the tank through the exhaust pipe 9. While repeating such operations,
The clogging of the floating filter material also progresses.

The progress of the clogging of the floating filter material layer can be caught by increasing the pressure in the tank. (The pressure gauge is not shown.) When the rise in pressure is caught, the cleaning water can be injected from the cleaning water pipe 7 to clean and regenerate the clogged floating filter material 2. The cleaning wastewater can be taken out of the tank by the drainage pipe 8. At this time, it is effective to increase the aeration amount from the air diffusing tube 6 because the stirring of the floating filter material 2 can be promoted. Further, by raising the discharge pipe in a U-shape, the floating filter medium 2 can be prevented from flowing away.

Next, in the case shown in FIG. 2, compared with the case shown in FIG. 1, the solid-liquid separation membrane 3 is buried in the filter medium layer, and the air diffuser 6
The operation is the same as in the case of FIG. 1, except that only the stock solution chamber 1a is provided. Further, the case shown in FIG. 3 is an open type processing tank 1 as compared with the case shown in FIG.

Further, the cases shown in FIGS.
While the case shown in FIG. 3 is a pressure filtration device for the water head H, suction filtration from the treated water side is adopted. The cleaning / reproducing device for the solid-liquid separation membrane 3 and the floating filter medium 2 and the effects thereof are the same as those in FIGS.

[0019]

As described above, according to the present invention, by providing a floating filter medium layer having a biological treatment function in the treatment tank and a solid-liquid separation membrane on the lower flow side of the treated raw water, the floating filter medium layer in the raw water can be treated. At the same time as capturing solids, organic substances that cannot be physically captured are decomposed, and then fine solids are captured by a solid-liquid separation membrane to obtain clear treated water.
The separation of solids and the biological treatment were carried out separately, but it is possible to treat them in one tank. In particular, since the solids are captured and removed by the floating filter material layer, the pollution load of the solid-liquid separation membrane part is reduced. It is low, and continuous filtration operation for a long time is possible, and the filtration efficiency can be significantly improved.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of a sewage treatment apparatus according to the present invention.

FIG. 2 is likewise a schematic vertical sectional view of another embodiment.

FIG. 3 is likewise a schematic vertical cross-sectional view of another embodiment.

FIG. 4 is likewise a schematic vertical cross-sectional view of another embodiment.

FIG. 5 is a schematic vertical sectional view of another embodiment of the present invention.

FIG. 6 is likewise a schematic vertical cross-sectional view of another embodiment.

[Explanation of symbols]

 1 Processing tank 2 Floating filter medium 3 Solid-liquid separation membrane

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location C02F 3/06 B01D 23/10 Z

Claims (1)

[Claims] 1. A flotation filter 2 is loaded into a treatment tank 1, and a solid-liquid separation membrane 3 is provided in the flotation filter layer or on the lower flow side of the treated water. And a treatment water take-out port in the upper part of the treatment tank 1.