JPH07290095A - Advanced intensive waste water treatment - Google Patents

Abstract

PURPOSE:To purify a waste water with the sludge minimized or eliminated. CONSTITUTION:This process is provided with a first stage consisting of catalytic oxidation by microorganism, filtration, separation and backwashing, a second stage consisting of oxidative decomposition of microorganism by dissolution of compressed air in the backwashing water generated in the first stage and normal-pressure bubble contact, autolysis and flotation concentration and a third stage for digesting and reducing the residual sludge generated in the second stage by the food chain of the protozoans and metazoans. The remaining water in the third stage is returned to the first stage, and purified water is obtained in the first stage.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to industrial wastewater of petroleum, petrochemical, food industry, large-scale cleaning industry, etc. and organic pollutants in general wastewater such as polluted rivers, lake water, sewage, etc.
Adsorption, mainly by the action of microorganisms, due to the microorganism adhesion carrier
Along with catalytic oxidative decomposition, growth or free microorganisms and SS (Suspended Solid: Suspended particles) are removed by filtration, and the filtered-out product can be recovered in backwash water for efficient decomposition and digestion reduction. Highly integrated wastewater treatment method.

[0002]

2. Description of the Related Art Regarding a method of treating wastewater utilizing the catalytic oxidation of microorganisms, various methods using a biofilm carrier have been used so far in order to replace the activated sludge method, which has the drawback of being versatile but vulnerable to load fluctuations. These types of high-performance processes have been individually researched and developed (for example, Japanese Patent Laid-Open No. 62-
No. 144799, Japanese Patent Laid-Open No. 63-77598,
See Japanese Patent Application Laid-Open No. 2-122891).

[0003]

However, by combining the above-mentioned conventional individual processes with an optimum flow, the total purification capacity from wastewater purification to sludge reduction is higher than that obtained by simple addition of individual processes. A combination wastewater treatment system that realizes performance improvement has not been developed yet.

The present invention solves the above-mentioned conventional problems. By optimally combining various types of individual high-performance processes utilizing microorganisms, which have been individually developed in the past, it is possible to add individual process capabilities. It is an object of the present invention to provide a highly-integrated wastewater treatment method that can obtain higher performance than that obtained and that enables purification treatment with minimal or no excess sludge generation.

[0005]

To this end, the highly integrated wastewater treatment method of the present invention comprises a first step consisting of a catalytic oxidation treatment by microorganisms, a filtration separation and a backwash treatment, and a backwash water generated in the first step. Second step consisting of oxidative decomposition of microorganisms by air pressure dissolution and contact with atmospheric bubbles, self-digestion and floating concentration, and third step of digesting and reducing the residual sludge generated in the second step by food chain of protozoa or metazoa And the residual water of the third step is returned to the first step to obtain the treated water purified in the first step. In addition,
Embodiments of the present invention include the following configurations.

(1) The first step is to perform intermittent backwash with a single-stage one-stage or multi-stage biological filtration device, or to alternately operate and backwash two-tank biological filtration devices, (2) In the two steps, first, oxygen is efficiently dissolved with pressurized air to catalytically oxidize and decompose SS and the like, and atmospheric pressure bubbles are brought into contact with each other to self-extinguish sludge and float and concentrate SS and sludge. That is, (3) the third step is to supply wastewater containing residual sludge to the lower part of the sludge digestion and reduction tank, first anaerobically digest it with an anaerobic filtration layer, and then, in the aerobic filtration layer, protozoa or metazoa. Digestion weight loss treatment with, then anaerobic digestion in the anaerobic filtration layer, (4) in the third step,
A funnel-shaped circulation pipe is provided in the center of the inside of the digestion reduction tank, and (5) a plurality of circulation pipes are arranged in the third step,
Connecting the drainage channel to the water collection pipe, (6) In the third step, the digestion and loss tank is a rectangular tank, divided by a plurality of circulation partition members, and a straightening vane is vertically arranged between the circulation partition members. To limit the free flow of the carrier, (7) in the third step, a bottomed tubular digestion and loss tank is partitioned by a plurality of tubular partition members, and multi-stage treatment is carried out, (8) second Use one multi-stage treatment tank for the process and the third process, and (9) apply the wastewater treatment method using a load-stabilizing pre-reactor before the third process.

[0007]

In the present invention, in the first step of the biological filtration treatment, the contaminants adsorbed and removed by the microorganism-carrying carrier, the catalytic oxidative decomposition and the filtration and removal function of the proliferating microorganisms and the like can be used to quickly and efficiently pollute the treated wastewater. Remove the components
Purified water is discharged or reused. In the second step, the backwash water generated in the first step is pressurized to enhance the oxygen dissolution efficiency, thereby efficiently catalytically oxidizing and decomposing polluted components, and highly efficiently self-digesting microorganisms and other polluted components. And reduce the amount of microorganisms. In the third step, the treated water containing the residual sludge generated in the second step is digested and reduced to the minimum level of the excess microorganisms in the treated water by utilizing the food chain of protozoa or metazoan.

Since a large amount of raw water is discharged after the biological filtration treatment in the first step, it is possible to reduce the size of the ordinary biological treatment apparatus to several tenths in all the first to third steps. Further, only the pollutant component concentrated and removed in the first step can be efficiently decomposed in the second and third steps.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a highly integrated wastewater treatment method 1 according to the present invention.
It is a flowchart which shows an Example.

In the first step as the first treatment, the waste water from the raw water tank is purified by a multi-stage biological filtration device composed of one tank, or it is constructed with a relatively small capacity as compared with the case of one tank. The tank biological filter is alternately operated and backwashed, and SS components and pollutants in the wastewater are adsorbed and catalytically oxidized by the action of microorganisms, and are removed by filtration with a filter medium. The first step can be combined with a three-phase flow treatment tank and an ordinary filtering device. The treated water clarified by separating and removing the pollutant components is discharged or reused. Backwash water containing a high concentration of SS and pollutants generated in the backwash operation when the pressure loss of the biological filtration tank increases in the first step is sent to the next second step.

In the second step, oxygen is efficiently dissolved (the amount of dissolution increases according to Henry's law) with pressurized air in the first step to carry out catalytic oxidative decomposition, and then the second step is usually performed with a diameter of several hundred μm. A pressure bubble (defining a bubble generated at normal pressure level) is brought into contact with the SS, and the sludge is self-extinguished to SS.
The sludge is floated and concentrated. The concentrated SS and sludge are circulated again to continue the two-step treatment. In the second step, the fine air bubbles having a diameter of several tens of μm generated from the first-stage pressurized air dissolution are not only oxidatively decomposed but also SS components,
Also useful for flotation and concentration of sludge. In this step, it is possible to efficiently dissolve oxygen in the circulating treated water by the pressurized air, so the decomposition digestion tank main body may be operated at normal pressure,
From the viewpoint of maintaining decomposition efficiency, operation under pressure is desirable.
Since the treated water treated in the second step in two stages contains excess sludge that cannot be reduced in this step, the treated water that can be continuously supplied until the next backwash water reception timing is used. Is returned to raw water and the residual sludge that has been floated and concentrated is sent to the next third step. In the second step, anaerobic treatment may be added after aerobic treatment.

In the third step, excess sludge in the treated water from the previous step is digested and reduced by a food chain used as food for protozoa or metazoa. Sludgeless wastewater purification operation becomes possible by designing and arranging this digestion reduction tank to the optimum capacity, returning the treated water in this step to the raw water tank and reprocessing it in the first step. In addition, when having an incinerator for surplus sludge, the final digestion and reduction tank may be made smaller and incinerated.

FIG. 2 is a view showing an example of an apparatus for carrying out the processing of the first step. In this example, two biological filtration wastewater treatment tanks 1 are connected in parallel. A metal or resin net member 2 is fixed to the upper portion of each wastewater treatment tank 1, and a filtration bed 3 is formed below the net member 2. The filter bed 3 is filled with a floating carrier 4 composed of a large number of particles, and the net member 2 prevents the floatable carrier 4 from flowing upward.

The floating carrier 4 is formed by molding a foamable polymer having a porous surface, a fibrous polymer, or styrofoam into a spherical shape, a pellet shape, a star shape, or the like to allow microorganisms to grow on the surface. And the carrier diameter (about 0.5 to 20 mm),
By changing the pore content and the specific gravity, the filtration performance and the microorganism adhesion performance of the filtration bed 3 are adjusted, and the clogging condition of the filtration bed 3 can be controlled. A filtration bed composed of a small-diameter carrier has a large amount of retained microorganisms and a high catalytic oxidation capacity, but a large increase in pressure loss, and is easily clogged. Therefore, especially in a multi-stage tank, the decomposition capacity and pressure loss are adjusted by combining the sizes of the carrier diameters. Further, in order to improve the dephosphorization efficiency, calcium carbonate powder or coral sand containing calcium carbonate, shells, etc. may be mixed in the filter bed 3, or a calcium carbonate component may be mixed in the carrier 4 for molding. Good.
These calcium carbonates need only be present in the tank to dephosphorize by a chemical reaction.

At the bottom of each wastewater treatment tank 1, a raw water supply pipe 5 is provided.
Are connected via on-off valves 5a, 5b, and backwash water drain pipe 6
Are connected via open / close valves 6a and 6b. Further, an air supply pipe 7 is provided in the middle portion of the filtration bed 3 with open / close valves 7a and 7b.
Connected through. At the top of each wastewater treatment tank 1,
The treated water drainage pipe 8 is connected via open / close valves 8a and 8b,
Further, the backwash water supply pipe 9 is connected via the on-off valves 9a and 9b. Further, a backwash pump 10 and an opening / closing valve 1 for circulating backwash water from the lower part to the upper part of the wastewater treatment tank 1.
1 is provided.

A method of treating the biological filtration device having the above structure will be described. First, the on-off valves 5a, 5b, 7a, 7
Open b, 8a and 8b to supply raw water and air to each wastewater treatment tank 1. After the raw water is subjected to an anaerobic treatment in the lower layer of the filter bed 3 where air is not supplied, the growth of microorganisms on the surface of the buoyant carrier 4 becomes active in the middle layer and above of the filter bed 3 to contaminate the wastewater. The substance is decomposed and removed by aerobic treatment by microorganisms, and the treated water is discharged from the treated water drain pipe 8 through the filter bed 3 and discharged or reused.

As the operation progresses, SS such as growing microorganisms and dead bodies of microorganisms adheres and blocks around the air supply position of the filter bed 3, so that the pressure loss increases. However, this pressure loss is detected by a sensor (not shown) and The wastewater treatment tank 1 is backwashed alternately. For example, when backwashing the wastewater treatment tank on the left side in the figure, the on-off valves 5a, 7a, 8a are closed to stop the supply of raw water and air, the on-off valve 11 is opened, and the backwash pump 1 is opened.
0 is driven, and the backwash pump 10 circulates in the filter bed 3 to disperse a part of the proliferating microorganisms attached to the filter bed 3 and the dead bodies of the microorganisms. Then, the on-off valves 9a and 6a are opened, and the backwash water supplied from the backwash water supply pipe 9 discharges the contaminated backwash water through the backwash water drain pipe 6 and sends it to the second step.

When the backwash of the wastewater treatment tank 1 on the left side in the figure is completed, the wastewater treatment is restarted again, and then the backwashing of the other wastewater treatment tank 1 is performed in the same manner. Thus, if the pressure loss increases in one wastewater treatment tank, the pressure loss is restored by backwashing the wastewater treatment tank while performing the treatment in the other wastewater treatment tank, and the wastewater treatment and the backwashing alternate. By repeating the above, the wastewater treatment can be continuously performed without stopping the operation. In addition, it is also possible to use three or more waste water treatment tanks 1. In addition, by installing a wire mesh under the air injection part,
The microflora of the anaerobic treatment section and the aerobic treatment section may be separately managed as a stage treatment tank.

FIG. 3 is a diagram showing an example of an apparatus for carrying out the processing of the second step. In the figure, 21 is a backwash water treatment tank, 22 is a cylindrical partition member, 23 is a straightening plate, 24 is a pressure regulating valve, 25 is a floating separation section, 26 is a concentrated sludge section, 27,
28 is a pump, 29 is a static mixer, 30 is a pressure pump, 31 is a gas-liquid contact mixer, 32 is a pressure reducing valve, 33
Is a bubble dispersion injection device.

The sludge-containing backwash water sent from the biological treatment apparatus of FIG. 2 is sent to the static mixer 29 together with the concentrated water containing the sludge floated and separated in the backwash water treatment tank 21, where the digestion gas is supplied. After being mixed with the pressurized air sent from the pipe 35, it is sent to the pressurizing pump 30 to be pressurized (for example, about 3 to 5 kg / cm ² G), and further sent to the gas-liquid contact mixer 31 to remove the air. Disperse finely and dissolve air (oxygen) under pressure. This step is a step of efficiently dissolving air in wastewater by a gas-liquid pressure treatment to promote a digestion reaction. That is, in aerobic digestion, oxygen is used as a raw material to decompose sludge into carbon dioxide, etc., but when dissolving air in a liquid, the solubility of oxygen is greater than that of nitrogen, etc. Since it is proportional to the pressure (Henry's law), the dissolution efficiency of oxygen is increased, and the decomposition efficiency of aerobic digestion can be improved.

The waste water discharged from the gas-liquid contact mixer 31 is decompressed to a normal pressure level by the pressure reducing valve 32, and then the bubbles are dispersed and injected into the waste water in the bubble dispersion injection device 33, and the gas-liquid injection pipe 34 is injected. After that, the floating separation unit 25 in the backwash water treatment tank 21
Is supplied to the lower part of the sludge, and the sludge adheres to the pressurized bubbles and the atmospheric bubbles and is floated and separated at high speed. Bubble dispersion and injection device 33
Has a cylinder 33b rotated by a motor 33a,
This is a device for dispersing the air sent from the digestion gas supply pipe 35 into fine bubbles and injecting it into waste water. The normal pressure bubbles can be generated by other means such as an air diffuser.

Pressurized air bubbles in the waste water that have flowed out of the pressure reducing valve 32 are fine air bubbles having a diameter of several tens to 100 μm. Since the air bubble diameter is small, it takes a long time to float and the digestion tank 21 is not enlarged. However, in the present embodiment, the bubbles are dispersed and injected into the wastewater at a normal pressure level in the bubble dispersion and injection device 33, and the bubble diameter is about 100 to several thousand.
By reattaching the atmospheric pressure bubbles having a relatively large value of μm, the floating speed in the floating separation unit 25 can be increased, so that the floating separation can be performed in a small digestion tank.

The sludge that is digested in the flotation / separation unit 25 and floated and separated at the same time becomes a concentrated liquid, and the concentrated sludge unit 2
6, the concentrated liquid containing this sludge is sent to the third step by the pump 28. Further, a part of the wastewater at a low place in the flotation / separation unit 25 is returned to the wastewater treatment of the biological filtration device of FIG. 2 through the raw water tank. The space above the backwash water treatment tank 21 has a capacity capable of sufficiently absorbing fluctuations in water level due to reception of backwash water. By the time until receiving the next backwash water, the amount of backwash water per batch reception is leveled, the separated water is continuously returned to the raw water tank, and the concentrated sludge is sent to the next third step.

FIG. 4 is a diagram showing an example of an apparatus for carrying out the treatment of the third step. In the figure, 51 is a sludge digestion and reduction tank, 52 is a raw water supply pipe, 53 is an air supply pipe, 54 is a floating carrier, 55 is a sedimentable carrier, 56 is an air trapping grid, 5
7 is an anaerobic three-phase fluidized bed, 58 is an aerobic three-phase fluidized bed, 59
Is an anaerobic filter layer, 60 is air bubbles, 61 is a wire mesh or slit, and 62 is a drainage channel.

The floating carrier 54 is the same as described above, and as the sedimentable carrier 55, granular activated carbon, porous polymer filter media, sand, anthracite, ceramic balls, etc. are spherical, pellet-shaped, star-shaped, etc. Molded (0.1mm
The diameter is about 20 mm) and the protozoa or metazoans are attached to the surface of the carrier. In addition, a method of adhering a protozoan or metazoan to the surface or pores of the carrier using a gel-like substance, or a method of kneading a microorganism or a protozoan or metazoan into the gel-like substance and molding into a granule is adopted. May be.

The wastewater containing the residual sludge generated in the step of FIG. 3 is supplied to the lower part of the sludge digestion reduction tank 51, and first, the inflow SS amount is leveled in the anaerobic three-phase fluidized bed 57 and the partial anaerobic digestion is performed. Then, in the aerobic three-phase fluidized bed 58,
Having a digestive loss function by protozoa or metazoa,
A part of the anaerobic filtration layer 59 at the uppermost part is anaerobically digested to improve the treated aqueous state. The air trapping grid 56 traps air rising from the lower part and discharges it to the outside. In the aerobic three-phase fluidized bed 58, the air supply pipe 53
In response to the supply of air from the plant, the pollutants in the treated wastewater are decomposed and the diameter of the carrier 55 increases due to the growth of microorganisms and protozoa or metazoans. Pushed upwards. While being pushed upward, the three phases of the treated water, the air bubbles 60 and the carrier 55 are mixed and collide with the air trapping lattice 56, so that the oxygen dissolution efficiency in the treated water is increased and the adhered and grown on the surface of the carrier 55. A part of the protozoa or metazoan is peeled off, the carrier 55 descends, and is again subjected to catalytic oxidation. A collision member may be provided above the three-phase fluidized bed 58 to scrape the surface of the carrier having an increased diameter. Residual water containing microorganisms and part of protozoa or metazoans is returned to the wastewater treatment of the biological filtration device of FIG.

In the above-mentioned digestion and reduction step, unlike a simple multi-step treatment of activated sludge, various carriers such as a biofilm-adhering carrier by a floatable or sedimentable carrier, or an entrapping immobilization gel by a gel mixed with cells having special performance are used. By managing the cells by utilizing them, the digestion efficiency can be improved.
In the previous studies, the cell load was 1 g / l · day.
It has been found that it can fully digest the food chain to the level. In addition, the main body of the digestion reduction tank can be constructed in multiple stages, and by combining aerobic or anaerobic treatment with a floatable or sedimentable carrier, it is possible to manage the bacterial flora, protozoa or metazoa in each stage.

5 to 9 are views showing another example of the apparatus for carrying out the processing of the third step. The same components as those in the embodiment of FIG. 4 are designated by the same reference numerals and the description thereof will be omitted.

In the embodiment shown in FIG. 5, the digestion and reduction tank 1 has a vertical cylindrical shape, and a funnel-shaped circulation pipe 63 is provided at the center of the inside, and a flow diverter plate 64 is arranged so as to face the funnel portion 63a of the circulation pipe 63. An example is shown. Upon receiving the supply of air from the air supply pipe 53, the microorganisms and protozoa or metazoan proliferate along with the decomposition treatment of pollutants in the treated wastewater, and the carrier 5
The diameter of 5 increases and is pushed upward as the air and treated water rise. In the middle of being pushed upward, treated water,
Since the three phases of the air bubble 60 and the carrier 55 collide with the funnel portion 63a, the efficiency of oxygen dissolution in the treated water is increased, and a part of the protozoa or metazoan attached and propagated on the surface of the carrier 55 is peeled off, so that the carrier 55 It descends in the circulation pipe 63 and is again subjected to catalytic oxidation. The residual water containing a part of the protozoa or metazoan is discharged through the drainage channel 62.
In order to improve the peeling effect, unevenness may be provided on the lower side of the funnel surface.

FIG. 6 (A) is a schematic plan view, and FIG. 6 (B) is a schematic sectional view showing a main part. In this embodiment, a plurality of circulation pipes 63 of the digestion and reduction tank 1 shown in FIG.
It shows an example in which is connected to the water collecting pipe 65.

FIG. 7 (A) is a schematic plan view, FIG. 7 (B) is a schematic cross-sectional view showing an essential part, FIG. 7 (C) and FIG. 7 (D).
[Fig. 3] is a schematic plan view showing an example of a current plate. In the present embodiment, the digestion weight loss tank 1 is a rectangular tank, is partitioned by a plurality of circulation partition members 66, and a rectifying plate 67 is arranged in the vertical direction between the circulation partition members 66 to allow free flow of the carrier. By limiting it, we are trying to improve the processing efficiency as a three-phase flow system with extrusion flow. The cross-sectional shape of the current plate 67 is shown in FIG.
Besides the lattice shape shown in FIG. 7C and the honeycomb shape shown in FIG. 7D, a circular shape or a triangular shape is adopted.

The embodiment of FIG. 8 shows an example of a three-stage type digestion and reduction tank. The inside of the bottomed tubular digestion and reduction tank 51 is partitioned by the tubular partition members 68, 69, 70 to form a first digestion tank 71, a second digestion tank 72 and a third digestion tank 73. ing. First digestion tank 71 and third digestion tank 7
3 is filled with a floating carrier 54, and the second digestion tank 72
A sedimentary carrier 55 is filled inside. Raw water containing residual sludge is subjected to aerobic treatment with pressurized air in the first and second digestion tanks and then to anaerobic treatment in the third digestion tank 73.

The embodiment shown in FIG. 9 has a bottomed cylindrical digestion and reduction tank 5
The first to fifth digestive tanks 71 to 75 are formed by the cylindrical partition member 68 and the radial partition member 69, and the raw water is subjected to the multistage treatment in order of the first to fifth digestive tanks 71 to 75. An example is shown. In the present multi-stage treatment, by providing a stable load reactor in the middle of the multi-stage, the advantage of stabilizing the microflora is obtained.

In the embodiments of FIGS. 8 and 9, it is possible to realize the entire system in two stages, the first process and the second process and the third process as one multi-stage processing tank. For example, by further increasing the capacity of the digestion tank 71 in the first stage of FIG. 9 to provide the decomposition and self-digestion weight loss functions in the second step, and configuring the second and subsequent steps by the digestion step of the food chain, further downsizing is possible. Become.

In the examples of FIGS. 4 to 9, the wastewater treatment method by the prereactor is applied to the preceding stage, the load on the prereactor is stabilized by monitoring the water quality, and as a result, the treatment after the prereactor is performed. By stabilizing and controlling the operation of the microflora of the system, it is possible to stabilize and improve the efficiency of digesting and reducing excess sludge by utilizing the food chain. Further, the embodiments of FIGS. 4 to 9 can be applied to a combination of general catalytic oxidation or anaerobic treatment using microorganisms.

[0036]

As is apparent from the above description, according to the present invention, by combining the individual high performance processes optimally, it is possible to obtain a higher performance than that obtained by adding the individual process capacities, Enables purification treatment with minimal or no sludge in highly integrated small equipment. Further, since the waste water purified by biological filtration in the first step has the SS content removed by filtration, it can be reused for tap water or the like. Further, in the present invention, since the equipment can be downsized, it becomes easy to treat even components that require a long time to decompose oil and the like by optimally designing the equipment capacity.

[Brief description of drawings]

FIG. 1 is a flow chart showing an embodiment of a highly integrated wastewater treatment method of the present invention.

FIG. 2 is a diagram showing an example of an apparatus for performing the process of the first step of FIG.

FIG. 3 is a diagram showing an example of an apparatus for performing the process of the second step of FIG.

FIG. 4 is a diagram showing an example of an apparatus for performing the process of the third step of FIG.

FIG. 5 is a diagram showing another example of an apparatus for carrying out the process of the third step of FIG.

6 shows another example of the apparatus for carrying out the treatment of the third step of FIG. 1, FIG. 6 (A) is a schematic plan view, and FIG. 6 (B) is a schematic cross-sectional view showing a main part. is there.

7 shows another example of the apparatus for carrying out the treatment of the third step of FIG. 1, FIG. 7 (A) is a schematic plan view, and FIG. 7 (B) is a schematic cross-sectional view showing the main part. 7C and 7D
FIG. 3 is a schematic plan view showing an example of a flow path partition plate.

8 is a diagram showing another example of an apparatus for carrying out the process of the third step of FIG.

FIG. 9 is a diagram showing another example of an apparatus for performing the process of the third step of FIG.

[Explanation of symbols]

1 ... Wastewater treatment tank, 3 ... Filtration bed, 4 ... Floating carrier, 5 ... Raw water supply pipe, 6 ... Backwash water drain pipe, 7 ... Air supply pipe, 8 ... Treated water drain pipe, 9 ... Backwash water supply pipe 21 ... Backwash water treatment tank, 25 ... Flotation separation part, 26 ... Concentrated sludge part 30 ... Pressurizing pump, 31 ... Gas-liquid contact mixer, 32 ... Pressure reducing valve 33 ... Bubble dispersion injection device, 51 ... Sludge digestion reduction tank , 52
... Raw water supply pipe 53 ... Air supply pipe, 54 ... Floating carrier, 55 ... Sedimentable carrier 56 ... Air trapping grid, 57 ... Anaerobic three-phase fluidized bed, 58 ...
Aerobic three-phase fluidized bed 59 ... Anaerobic filtration bed, 60 ... Air bubbles, 62 ... Drainage channel, 63
... circulation pipe 66 ... partitioning member, 67 ... rectifying plate, 68,69,70 ... partitioning member 71-75 ... digestion tank

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication location C02F 3/08 ZAB B 3/32 ZAB (72) Inventor Shoichi Mori Nishi Oimachi, Iruma-gun Saitama Prefecture Tsurugaoka 1-3-1 Tonen Co., Ltd. Research Institute

Claims (1)

[Claims] 1. A first step consisting of a catalytic oxidation treatment by a microorganism, a filtration separation and a backwash treatment, and the backwash water generated in the first step is dissolved by air under pressure and the oxidative decomposition of the microorganism by an atmospheric pressure bubble contact, and a self-digestion. And a second step consisting of flotation concentration,
It comprises a third step of digesting and reducing the residual sludge generated in the second step by the food chain of protozoa or metazoa, returning the residual water of the third step to the first step, and treating the treated water purified in the first step. A highly-integrated wastewater treatment method characterized by obtaining.