JPH07290078A - Three-phase fluidized biological treating device - Google Patents

Abstract

PURPOSE:To hold a large number of high-activity microorganisms in a waste water treating tank and efficiently treat waste water with a small-sized equip ment by providing a collision member for a carrier to collide with in the waste water treating tank wherein the three phases of waste water, air and biological membrane carrier are fluidized in a mixed state. CONSTITUTION:A raw water feed pipe 2 and an air feed pipe 3 are connected to the lower part of a waste water treating tank 1, and a treated water discharge pipe 4 is connected to the upper part. Meanwhile, a precipitable carrier 5 to be deposited with a microbial membrane is packed in the tank 1, and two partition members 6 fixed in the shape of plate are furnished to form an upward passage 7 and a downward passage 8. In this case, many collision members 9 are set in plural stages at the upper part in the upward passage 7. Consequently, the treated water is forced upward, the three phases of treated water, air and carrier 5 are collided with the collision member 9, oxygen is more efficiently dissolved in the treated water, the microbial membrane deposited and propagated on the carrier 5 surface is released, and the waste water is efficiently treated.

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.
When using a biofilm carrier to which microorganisms are attached to decompose and purify by anaerobic or aerobic action, the amount of microorganisms attached to the surface of the carrier is limited by a collision member to improve the decomposition efficiency and high efficiency of organic pollutants. The present invention relates to a three-phase fluid biological treatment device capable of maintaining a high active microbial adhesion holding amount.

[0002]

2. Description of the Related Art A three-phase fluid biological treatment method is a method in which three phases of waste water (liquid), air (gas) and biofilm carrier (solid) to be treated are mixed and flow to decompose organic pollutants in the waste water. Although it is a method of removing, the microorganisms on the surface of the carrier grow over time as the wastewater treatment operation increases, and the amount of microorganisms attached increases.As a result, the carrier with an increased apparent diameter floats above the treatment equipment and The carrier holding amount of the carrier may decrease or the carrier may flow out. In order to solve this problem, conventionally, a mechanical peeling device is provided on the upper part of the treatment tank or outside the treatment tank to remove a part of the growing microbial film by peeling to remove the amount of microorganisms attached to the carrier surface. It is controlled so that the processing ability is maintained (see, for example, Japanese Patent Laid-Open No. 62-
No. 121697).

[0003]

Generally, in a biofilm-adhering carrier, the effective microorganism holding amount per unit volume of the treating tank increases if the apparent diameter of the microorganism adhering to the treating tank is small. It is possible to maximize the total amount of microorganisms in the stock. Also, if the amount of adhered microorganisms on the carrier surface can be controlled to a fixed amount by mechanical peeling during operation processing, the carrier surface can always be covered with a highly active bacterial layer of young age, resulting in the decomposition of pollutants. High activity can be maintained. That is, even if a large amount of aged microorganisms having a large age are attached and retained in the main body of the apparatus, the decomposition activity is low. However, in the conventional method of mechanically removing the microorganisms on the surface of the carrier, a separate peeling device is required, so that the equipment becomes complicated and the equipment cost increases, and especially in the method using the rotation mechanism for peeling, the maintenance cost is high. Has the problem of increasing.

The present invention is to solve the above-mentioned conventional problems, and is capable of retaining a large amount of microorganisms in a wastewater treatment tank with high activity, and enables efficient wastewater treatment with a small-sized facility. The purpose is to provide a device.

[0005]

Therefore, the three-phase fluidized biological treatment apparatus of the present invention is provided with a wastewater treatment tank for flowing three phases of wastewater, air and a biofilm carrier in a mixed state, and a wastewater treatment tank provided in the wastewater treatment tank. And a collision member having various shapes for colliding the carrier. In addition, as an embodiment of the present invention, the following configurations can be mentioned.

(1) A structure in which a circulation flow path consisting of an ascending flow path and a descending flow path is formed in a wastewater treatment tank, and a collision member is disposed in the ascending flow path, (2) the collision member is A structure in which a large number of rectangular plates are arranged in multiple stages, each plate is inclined and fixed in each stage, and the upper and lower plates are fixed so that their arrangement directions are orthogonal or intersect. (3) The collision member has a structure in which the plates are tilted in the vertical direction and arranged in a staggered manner. (4) The collision member has a plurality of pipes arranged in multiple stages, and the upper and lower pipes are arranged in the arrangement direction. Fixed at a right angle or crossing,
(5) a structure in which the collision member is a static mixer, (6) a structure in which the collision member is a propeller-shaped member, (7) a structure in which the collision member is a twisted rectangular non-woven fabric or a metal thin plate,
(8) The collision member is an ellipse-shaped member whose upper opening is an elliptical shape and spreads in an umbrella shape as it goes to the lower portion.The members are arranged in multiple stages, and the upper and lower members are arranged so that the major axes of the ellipses intersect. Composition, (9)
The collision member is a plurality of non-woven fabrics cut in a wakame shape, and a configuration in which the lower part or both of the non-woven fabrics are supported by a support member
(10) A structure in which an auxiliary air supply pipe for supplying air to the descending flow path is arranged, (11) A structure in which a post-treatment filtration tank consisting of an air trapping grid and a floating carrier is added, (12) an air deflector plate and sedimentation A structure in which a post-treatment filtration tank made of a permeable carrier is added, and (13) a structure in which an anaerobic treatment layer is provided below the air supply unit.

[0007]

In the present invention, when the three phases of wastewater (liquid), air (gas) and biofilm carrier (solid) are made to flow in a mixed state in the wastewater treatment tank, the flowing three phases are collided with the collision member. Improve the oxygen dissolution efficiency, and also make it possible to peel off a part of the microbial film adhering to the surface of the carrier.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 6 are cross-sectional views showing respective embodiments of the three-phase flow biological treatment apparatus of the present invention.

First, the embodiment shown in FIG. 1A will be described. A raw water supply pipe 2 and an air supply pipe 3 are connected to a lower portion of a wastewater treatment tank 1 having a rectangular shape in a plan view, and a treated water drainage pipe 4 is connected to an upper portion of the wastewater treatment tank 1. The wastewater treatment tank 1 is filled with a sedimentable carrier 5 for attaching a microbial membrane. In addition, in the wastewater treatment tank 1,
Two plate-shaped partition members 6 are fixed in the vertical direction,
The partition member 6 forms an ascending channel 7 and a descending channel 8 so that the carrier 5 can circulate between the ascending channel 7 and the descending channel 8 to flow. Then, raw water and air are supplied to the lower portion of the ascending flow path 7 from the raw water supply pipe 2 and the air supply pipe 3.

In this embodiment, a large number of collision members 9 are arranged in a plurality of stages between the two partition members 6 in the upper part of the ascending flow path 7. The collision member 9 is formed of a rectangular plate, each plate is inclined and fixed in each stage, and the upper and lower plates are arranged at right angles in the disposing direction.
Or they are fixed so that they intersect. A drainage channel 11 provided with a metal net 10 is formed in the upper part of the ascending flow path 7, and the treated water containing the separated microorganisms can be discharged from the treatment drainage pipe 4 while preventing the carrier 5 from flowing out by the metal mesh 10. ing. The rectangular plate may be provided with unevenness on the surface or may be provided with openings of various shapes. Further, the same collision effect can be obtained by laminating a plurality of flat plates having openings of various shapes. Further, instead of the wire net 10, a slit or a punching plate may be used.

The sedimentable carrier 5 is formed by molding granular activated carbon, porous polymer filter material, sand, anthracite, ceramic balls or the like into a spherical shape, a pellet shape, a star shape, etc. The processing performance is adjusted by changing the pore content rate, the surface unevenness density, and the specific gravity. Further, in order to improve the dephosphorization efficiency, a calcium carbonate component may be mixed in the filter medium.

The operation of this embodiment having the above structure will be described. When raw water and air to be treated are supplied into the wastewater treatment tank 1, the decomposition of pollutants in the treated wastewater causes the microorganisms to proliferate and the diameter of the carrier 5 to increase. Road 7 is pushed upwards. While being pushed upward, the three phases of the treated water, air and carrier 5 collide with the collision member 9, so that the oxygen dissolution efficiency in the treated water is increased and a part of the microbial film adhered and grown on the surface of the carrier 5 is removed. When the carrier 5 is peeled off and exits the ascending flow path 7, the carrier 5 descends through the descending flow path 8 and is again supplied into the ascending flow path 7 and used for catalytic oxidation. As a result, the apparent diameter of the carrier 5 can be limited to an equilibrium value peculiar to the system, the carrier density in the circulating liquid can be kept high, and a large amount of microorganisms in the wastewater treatment tank 1 can be retained with high activity. As a result, efficient wastewater treatment with small equipment becomes possible.

Next, another embodiment of the present invention will be described with reference to FIGS. 1 (B) to 6 (C). The same components as those in the embodiment of FIG. 1A are designated by the same reference numerals and the description thereof will be omitted.

In the embodiment shown in FIG. 1B, four partition members 6 are vertically fixed in the wastewater treatment tank 1, and these partition members 6 provide two ascending passages 7 and descending passages 8. Is formed so that the carrier 5 can circulate and flow between the ascending flow path 7 and the descending flow path 8. Then, a large number of plate-shaped collision members 9 are arranged in a zigzag manner in the upward flow path 7 while being inclined in the vertical direction. In this embodiment, raw water and air are supplied by one pipe.

In the embodiment shown in FIG. 1C, a large number of collision members 9 are provided between the two partition members 6 in the upper part of the ascending flow path 7.
Are arranged in a plurality of stages. The collision member 9 is composed of a plurality of pipes, and the upper and lower pipes are fixed so that the arrangement directions thereof are orthogonal or intersect. Also, 2
The upper part of the partition member 6 is formed in a funnel shape so that the opening is narrowed, and an air distribution plate 12 is provided above the opening. In the case of the present embodiment, after the three phases collide with the collision member 9, a vortex is formed in the upper part of the pipe, so that there is an advantage that the separation effect and the oxygen dissolution efficiency are increased.
The collision member 9 may have a circular cross section, a polygonal cross section, an X-shaped or Y-shaped cross section, or an uneven surface.

Each of the embodiments shown in FIG. 2 shows an example in which a rotational force is applied when the three phases are collided to further enhance both the effect of oxygen dissolution and the separation due to the collision. Although the wastewater treatment tank 1 and the partition member 6 are cylindrical in this embodiment,
The upper part of the wastewater treatment tank 1 may be an open type.

In FIG. 2 (A), a static mixer is adopted as the collision member 9 provided in the ascending flow path 7. The static mixer has multiple swivel plates 9 inside.
It has a structure in which a and 9b are fixed, and swivel plates 9a and 9b.
Is formed, for example, by twisting a rectangular plate 180 ° to the right or left, and the swiveling plates 9a having the same or opposite twist directions.
9b are arranged alternately and with their ends orthogonal to each other. In FIG. 2 (B), the collision member 9 is composed of a propeller-shaped member and a donut-shaped baffle plate, and FIG.
In the above, the rectangular non-woven fabric and the metal thin plate are arranged with a twist. In this embodiment, if the collision member 9 itself is made of a non-woven fabric or the like to move, the three-phase contact effect can be further enhanced.

3A and 3B show still another embodiment of the present invention. FIG. 3A is a sectional view of an essential part and FIG. 3B is FIG. 3A.
FIG. 4 is a sectional view taken along line BB in FIG. In this embodiment, as the collision member 9, a member having an elliptical shape with an upper opening that spreads in an umbrella shape as it goes to the lower side is used. The long axes are arranged at right angles or intersect to enhance the collision effect. In addition, instead of the collision member 9, a vertical partition member that restricts the flow in the horizontal direction may be provided, unevenness may be provided on the surface, or a filling contact member having many voids may be provided to obtain the same collision effect. You can

FIG. 4 is a cross-sectional view of an essential part showing still another embodiment of the present invention. In the embodiment of FIG. 4 (A), a plurality of non-woven fabrics cut in a wakame shape are used as the collision member 9, and only the lower end of the non-woven fabric is supported by the support member 13 to obtain the collision effect. . In the present embodiment, the nonwoven fabric oscillates, so that the effect of improving the contact efficiency of the three phases is further enhanced. In the embodiment shown in FIG. 4 (B), as the collision member 9, a large number of members such as a circular shape and a propeller shape are held on a vertical shaft. Alternatively, a coil-shaped or curled string-shaped filter medium may be held.

FIG. 5 is a sectional view showing still another embodiment of the present invention. In this embodiment, an auxiliary air supply pipe 15 for supplying air to the descending passage 8 is provided. In the present embodiment, the amount of auxiliary air is smaller than that of the main air supplied to the ascending flow path 7, the entire three phases are circulated by the relatively strong levitation force of the main air, and anaerobic in the descending flow path 8. It is possible to supply a large amount of oxygen by injecting air at two places and further improving the processing capacity. It is also possible to improve the gas-liquid contact effect by providing a spiral flow deflector or a small amount of collision member inside the descending flow path 8.

FIG. 6 is a sectional view showing still another embodiment of the present invention. In this embodiment, an example in which a filtration tank is combined with the above-mentioned processing tank as a post-treatment is shown. In the embodiment shown in FIG. 6A, a post-treatment filtration tank 17 including an air trapping grid 16 and a floating carrier is provided. Figure 6
In the embodiment of (B), a post-treatment filtration tank 19 composed of an air distribution plate 18 and a sedimentable carrier is provided. FIG. 6 (C)
In the embodiment, a three-stage treatment in which a space is provided between the raw water supply pipe 2 and the air supply pipe 3 and a layer 20 for reducing the flow velocity of the carrier 5 to reduce the flow velocity of the carrier 5 is provided below the air supply pipe 3. Shows an example of. In this example, a flow restricting partition plate may be provided at the bottom of the air supply pipe 3 to form an extruded flow layer, and a multi-stage treatment of three or more stages is also possible.

Although the respective embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and various modifications can be made. For example, arranging members in the vertical direction in the horizontal direction and vice versa. In addition, although the method of naturally attaching the microorganisms to the carrier 5 is adopted in the above-mentioned examples, a method of attaching the microorganisms to the surface or the pores of the carrier using a gel-like substance, or to the gel-like substance You may employ | adopt the method of kneading and mixing a microorganism and shape | molding it in a granular form.

Further, the ascending flow path 7 can be obtained by modifying the examples shown in FIGS. 1B and 6A without providing the partition member 6, for example.
If the descending flow path 8 can be formed, the effect of the present invention can be obtained.

Further, in the above-mentioned embodiment, the aerobic treatment for supplying air is mainly explained, but instead of supplying air, the decomposition gas generated in the anaerobic treatment is injected to remove the raw water and the carrier. It may be applied to the anaerobic treatment process so as to obtain a collision effect and limit the amount of microorganisms adhering to the carrier surface by circulating at a high speed.

In addition, the present invention is directed to SS of exfoliated microorganisms and the like.
(Suspended Solid: Suspended particles) can be treated in the latter stage, which is effective in the preceding stage of multi-stage biological treatment.

[0026]

As is apparent from the above description, according to the present invention, it is possible to prevent the amount of attached biofilm from adhering more than necessary, so that the amount of highly active microorganisms retained per unit volume of the wastewater treatment tank is high. It can be maintained, and as a result, highly efficient wastewater treatment can be realized with a small facility. Also,
Since no peeling device such as a rotating machine is provided in the wastewater treatment tank, operation and maintenance of the device are facilitated. Further, since the three-phase forced circulation is used as the usual base in the entire wastewater treatment tank, there is no process instability element such as carrier clogging, and stable wastewater purification operation management becomes easy. According to the present invention, the higher the height of the apparatus body is, the more the collision speed can be increased, the oxygen dissolution efficiency can be improved, and the installation area can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing each embodiment of a three-phase fluid biological treatment device of the present invention.

FIG. 2 is a cross-sectional view showing each embodiment of the three-phase fluid biological treatment device of the present invention.

FIG. 3 shows still another embodiment of the present invention, and FIG.
Is a cross-sectional view of a main part, and FIG. 3B is a cross-sectional view taken along the line BB of FIG.

FIG. 4 is a sectional view of an essential part showing still another embodiment of the present invention.

FIG. 5 is a sectional view showing still another embodiment of the present invention.

FIG. 6 is a sectional view showing still another embodiment of the present invention.

[Explanation of symbols]

1 ... Wastewater treatment tank, 2 ... Raw water supply pipe, 3 ... Air supply pipe, 4
... Treated water drain pipe 5 ... Carrier, 6 ... Partition member, 7 ... Upflow passage, 8 ... Downflow passage, 9 ... Collision member

Claims (1)

[Claims] 1. A waste water treatment tank for flowing three phases of waste water, air and a biofilm carrier in a mixed state, and a collision member provided in the waste water treatment tank for colliding the carrier. Three-phase fluid biological treatment equipment.