JP2001276865A - Spiral microorganism carrier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microorganism carrier that shows sufficient long-term service durability, is hardly deformed and gives a fixed bed filled with the carrier which is hardly compacted and thereby, the water passage resistance of which is hardly increased. SOLUTION: The production process of this microorganism carrier 10 comprises a stage A for spreading a sheetlike water-permeable member 1 on a flat supporting base plate 4, a stage B for spirally winding up the sheetlike member 1 from its one end until the diameter of the resulting wound-up body reaches a prescribed value, a stage C for subjecting the other free end of the member 1, being on the outside, to fusion bonding to the outer surface of the spirally wound-up body with a fusion bonding machine 5, and a stage D for producing the objective microorganism carrier 10. After the stage C, a long, narrow bar-like body can optionally be cut into pieces each having appropriate length.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a spiral microorganism carrier. More specifically, the present invention relates to a microorganism carrier suitably used for a sewage purification tank for biologically treating wastewater (sewage) such as domestic wastewater or organic industrial wastewater discharged from a household, a method for producing the same, and a sewage purification tank.

[0002]

2. Description of the Related Art When biological wastewater such as domestic household wastewater or organic industrial wastewater is biologically treated in a sewage treatment tank, microorganisms such as activated sludge are used as microorganism carriers (became a home for microorganisms. A sewage purification tank is widely used in which wastewater is attached to microbial adhering bodies and treated by contacting wastewater with the wastewater. Conventionally, various carriers are known as microorganism carriers, for example, a fiber mass carrier in which single fibers are bound or entangled, a sponge-like polyethylene open-cell foam, and the like.

[0003]

The above-mentioned fibrous bulk carriers and sponge-like polyethylene open-cell foams are suitable as a habitat for microorganisms or as a filter material for suspended solids (SS), but they have low stiffness, There is also a problem that a part thereof is deformed while being used for a long period of time, and a fixed bed filled with the material is compacted to increase water flow resistance. An object of the present invention is to provide a microbial carrier that is resistant to deformation for a long period of time and is less likely to be deformed or to have a compacted bed filled with the same, thereby reducing water flow resistance.

[0004]

Means for Solving the Problems In order to achieve the above object, the microorganism carrier of the present invention has the following constitution. That is, the microorganism carrier of the present invention comprises a sheet-like water-permeable member 1
Is a microorganism carrier 10 which is spirally wound.

[0005] The sheet-like water-permeable member 1 may be one in which two different types of sheet-like water-permeable members are overlapped.

When two different types of sheet-like water-permeable members are used, one type may be for the purpose of adhering and holding microorganisms, and the other type may be for the purpose of preventing deformation (reinforcing material).

The sheet-like water-permeable member 1 is selected from water-permeable members such as a sheet-like mesh, a fiber material, or a porous body (foam).

[0008] The present invention also relates to a method for producing the microorganism carrier. That is, one side of the sheet-like water-permeable member 1 is wound in a spiral shape in the direction of the other side opposite to the other side as a core (center axis) until a predetermined thickness is reached. A free end of the sheet-like water-permeable member is fixed to the winding surface.

In this manufacturing method, the order of separating the remaining portion and fixing the free end can be switched, and the remaining portion can be cut off after the free end is fixed.

The swirl obtained by such a method is
Further, it can be cut into an appropriate length to obtain a microorganism carrier.

The present invention further relates to a sewage treatment tank provided with the above-mentioned microorganism carrier in a tank. The sewage purification tank is, in order from the upstream, an anaerobic filter bed tank, an aerobic filter bed tank, a sewage purification tank having a treatment water tank and a disinfection tank, and the like. It is a septic tank filled with a carrier.

In the present invention, the term "sheet" means a film or sheet having a thickness of 0.05 mm to 6 mm. Preferably, the thickness is 0.1 mm to 4.0 mm
(More preferably, a film or a sheet having a thickness of 0.1 mm to 2.0 mm). These numerical ranges are defined in relation to the size of the microorganism carrier (cochleate) to be produced.

[0013] The "predetermined thickness" refers to the main purpose of the microorganism carrier (filter material, contact material or bioreactive material).
And the type of use (for fluidized bed and fixed bed)
Preferably, it is 5 mm to 30 mm.

[0014]

The microbial carrier of the present invention is formed by spirally winding a sheet-like water-permeable member, and exhibits a kind of sponge-like characteristic in which the whole is communicated from the outside to the core. In addition to the function of, there is also the function of a filtering material. It also has some resistance to external forces. In a microorganism carrier produced by superposing two different types of sheet-like water-permeable members, one is mainly responsible for adhesion and retention of microorganisms, and the other is for deformation prevention (reinforcing material). .

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a method for producing a microorganism carrier will be described. FIG. 1 is a process diagram illustrating an example of a method for producing a microorganism carrier according to the present invention. The sheet-like water-permeable member (mesh body in the figure) 1 is spread on the flat support 4 (step A), and spirally wound from one end to a predetermined thickness (step B). Then, the outer free end is welded to the rolled-up surface using the welding machine 5 (step C). Then, the microorganism carrier 10 is obtained (step D). Instead of the welding machine 5, it may be bonded by a heater, ultrasonic waves or the like, or may be bonded by an adhesive. Here,
After the step (C), usually, a cutting step (omitted in FIG. 1) is included, and the elongated rod-like material after welding is cut into a length suitable for the microorganism carrier. Although a material having a width that does not need to be cut from the beginning may be used, it is more efficient to cut later using a material having a long width.

As the sheet-like water-permeable member 1 to be used, a mesh body (net-like molded body), a porous body (foamed body), a fiber material or the like is used. The material of the mesh body or the porous body (foam) is made of a thermoplastic resin such as polyvinyl chloride, polyvinyl formal, polyethylene, polypropylene, ethylene-vinyl acetate copolymer, polystyrene, etc., or a heat-resistant material such as polyurethane, phenol, urea and melamine. There is a curable resin. Since it is rolled up and formed, a material having elasticity such as rubber is preferable.

[0017] The net-shaped molded body has a specific gravity of 1
If it is smaller (for example, polyethylene has a specific gravity of about 0.9
4. Polypropylene has a specific gravity of about 0.93), and a filler having a specific gravity of more than 1 such as calcium carbonate, magnesium silicate, calcium sulfate, barium sulfate, zeolite, activated carbon or the like is added thereto, and molded to adjust the specific gravity to approximately 1. It may be something. As the porous body (foam), the expansion ratio (total volume of the porous resin including pores / volume of the resin itself other than the pores in the porous resin) is about 5 to 25 times, and each air bubble is formed. It is preferably used because the bubbles that are torn and communicate can penetrate the liquid to the inside.

Examples of the fiber material include inorganic fibers, plant fibers, and synthetic fibers. From the viewpoints of microbial resistance, durability, adhesion, and the like, synthetic fibers are preferred. Synthetic fibers include polyester fiber, acrylic fiber, nylon fiber,
Examples include vinylon fiber, polyethylene fiber, polypropylene fiber, and vinylidene fiber. Woven or nonwoven fabrics are preferably used.

In addition, in order to facilitate the winding, the sheet-shaped water-permeable member 1 and the core material may be used for winding. A core is present at the center of the microbial carrier thus obtained. The shape of the core material is a rod shape, a tubular shape, a net-like tubular shape, or the like, and the material is preferably a synthetic resin from the viewpoints of microbial adhesion, processability, corrosiveness, and the like.

FIG. 2 shows another example of a method for producing a microorganism carrier according to the present invention, in which two different (two) sheet-like water-permeable members (P and Q) are used, and one of the two sheets has a microorganism-containing material. This is an example in which a sheet-like water-permeable member P (2) for the purpose of adhesion and holding is used, and a sheet-like water-permeable member Q (3) for the purpose of preventing deformation (reinforcing material) is used for another sheet.

The sheet-like water-permeable member P (2) and the sheet-like water-permeable member Q (3) are overlapped (step A), spirally wound from one of the overlapping ends (step B), and a welding machine is used. The outer end is welded to the rolled-up surface using Step 4 (Step C) to manufacture the microorganism carrier 10 (Step D). Here, after the step (C), a cutting step may be usually included. In this case, the outermost periphery of the spiral may be a sheet-like water-permeable member P (2), but is preferably a sheet-like water-permeable member Q (3). Water-permeable reinforcing material Q
By setting (3) as the outermost periphery, even if the microorganism carrier 10 flows in the sewage purification tank, the sheet-like water-permeable member P (2)
This is because they do not directly collide with each other and are not easily damaged.

The preferred specific gravity of the microorganism carrier to be produced is somewhat different between the fluidized bed and the fixed bed, but is preferably about 1 in order to have fluidity in the liquid. Sheet-shaped water-permeable member P
When a cell-connected foam resin sheet having a specific gravity of less than 1 (for example, polyethylene having a specific gravity of about 0.94 and polypropylene having a specific gravity of about 0.93) is used as (2), a sheet-like water-permeable member to be overlapped is used. As Q (3), a fiber material having a specific gravity larger than 1 (for example, a polyester fiber (specific gravity of about 1.38), a nylon fiber (specific gravity of about 1.1)
4), vinylon fiber (specific gravity of about 1.26) and vinylidene fiber (specific gravity of about 1.7) are preferable, and the microorganism carrier (total)
Can be adjusted to approximately 1. Sheet-shaped water-permeable member Q
Also in the case of superimposing a mesh body (net-like molded body) as (3), it is similarly preferable to use a mesh body having a specific gravity larger than 1.

The spiral body (elongated object) thus obtained
Is usually the purpose and location of application (anaerobic or aerobic
Alternatively, according to the fixed bed or the fluidized bed) or the like, the substrate is cut into optimal dimensions as appropriate to obtain a microorganism carrier.

As described above, the general shape of the microorganism carrier (spiral body) is usually a columnar shape. The core may be hollow. The dimensions of the cylinder are appropriately varied depending on the usage form of the fluidized bed, fixed bed and the like. For example, for a fluidized bed, the diameter and length of a cylinder are generally 5 mm to 30 mm (more preferably 6 mm to 20 mm) from the viewpoint of fluidization.
And Also, in the case where the contact material and the filtering material are used for a fixed bed and also have a filtering function, the diameter and the length of the column are approximately 5 mm.
About 30 mm (more preferably, 6 mm to 20 mm). When a contact material is used for a fixed bed, a thin spiral body is kept long without cutting it short (from 500 mm in length).
Approximately 5mm to 500mm
It may be used after being cut to a length. The general shape of the microbial carrier (spiral) may take the form of a prism (quadrilateral), polygonal prism, or the like, which is a cylindrical deformation.

FIG. 3 is an example of a sewage purification tank (schematic sectional view) provided with the microorganism carrier of the present invention in a tank. The sewage purification tank 21 is disposed in the order of an anaerobic filter bed tank (first chamber) 22, an anaerobic filter bed tank (second chamber) 23, an aerobic filter bed tank 24, a treatment water tank 25, and a disinfection tank 26 from the upstream side. I have. Sewage purification tank 2
1 is a blower 2 for sending air to the aerobic filter bed tank 24 and the like.
7 are provided. The aerobic filter bed tank 24 is provided with an air diffuser 28 and a sludge discharge member 29 below the filter bed, and a return pipe 30 is connected to the sludge discharge member 29.

Instead of the anaerobic filter tank (first chamber) 22 and the anaerobic filter tank (second chamber) 23, only a sedimentation separation tank may be provided. May be provided. Further, a sedimentation tank may be provided instead of the treatment water tank 25. Also, a manhole and a manhole cover 31 for closing the manhole are provided so that the inside of each tank can be inspected from above.

The microorganism carrier of the present invention comprises an anaerobic filter tank (first chamber) 22, an anaerobic filter tank (second chamber) 23 and an aerobic filter tank 2.
No. 4, or all of them may be filled. The filter bed of the anaerobic filter tank (first chamber) 22, the anaerobic filter tank (second chamber) 23, or the aerobic filter tank 24 may be a fixed bed or a fluidized bed.

In the sewage purifying tank 21, the waste water is treated as follows. First, the wastewater enters the upper part of the anaerobic filter bed tank (first chamber) 22 from the inflow port 32 and flows downward to the lower part of the tank.
At this time, the anaerobic filter bed (first chamber) 22 has an anaerobic filter bed 33.
During the passage through the anaerobic filter bed 33, the organic matter is decomposed by the anaerobic microorganisms attached to the anaerobic filter bed 33, and the solid matter precipitates near the lower part of the tank. Anaerobic filter bed tank (first room)
The wastewater treated in 22 passes from the lower part of the anaerobic filter bed 33 to the upper part of the anaerobic filter tank (second chamber) 23 through the advection part, and flows downward to the lower part of the tank. At this time, in the anaerobic filter bed tank (second chamber) 23, while passing through the anaerobic filter bed 34, further solid substances are captured and organic substances are decomposed by anaerobic microorganisms, and solid substances precipitate near the lower part of the tank.

The wastewater treated in the anaerobic filter bed (second chamber) 23 passes through the advection section from below the anaerobic filter bed 34 and enters above the aerobic filter tank 24. In the aerobic filter bed tank 24, the air sent from the blower 27 is used to maintain the aerobic state.
8 is discharged. The water flows downward to the bottom of the tank. At this time, while passing through the aerobic filter bed 35, solid matter adheres (or is trapped) and decomposition of organic matter by the aerobic microorganisms adhering to the aerobic filter bed 35 proceeds. The aerobic filter bed 35 of the aerobic filter bed tank 24 is filled with a microbial carrier, whereby organic matter is efficiently decomposed.

The waste water treated in the aerobic filter bed tank 24 enters a treated water tank 25 as treated water, and reaches a disinfecting tank 26 provided above the treated water tank 25. The treated water disinfected in the disinfection tank 26 is discharged from the discharge port 21 to the outside.

[0031]

Advantages of the Invention 1) The microorganism carrier of the present invention is a whirlpool and therefore is not easily deformed. In addition, since water easily penetrates into the interior, the whole becomes a habitat for microorganisms (contact material), and a microorganism carrier having a high drainage treatment function can be obtained. In a spiral body in which a sheet-shaped water-permeable member having a large wire diameter is used or a sheet-shaped water-permeable member for the purpose of preventing deformation (reinforcing material) is superposed, deformation is more difficult. 2) According to the production method of the present invention, the present invention can be achieved by simply winding up one or two different sheet-like water-permeable members in a spiral shape and fixing the end portion (there may be a step of cutting if necessary). Can easily be produced. Further, the specific gravity of the microorganism carrier can be easily adjusted by adjusting the selection, combination, and weight ratio of the materials. In addition, it is possible to create a slight gap between the sheet-like water-permeable members, or to impart hydrophilicity by selecting a material (this facilitates the movement of drainage and dissolved oxygen to the inside of the microorganism carrier). And a microbial carrier with high processing performance). 3) In the sewage purification tank of the present invention, the tank is provided with a microorganism carrier which is strong against external force and can attach a large amount of microorganisms, so that wastewater can be treated stably.

[Brief description of the drawings]

FIG. 1 is a process diagram illustrating an example of a method for producing a microorganism carrier according to the present invention. (A) is a state in which the sheet-like water-permeable member is spread on a support table, (a) is a cross-sectional view, (b) is a perspective view,
(B) is a step of winding up in a spiral (cross-sectional view), (C)
(D) is the obtained microbial carrier, (a) is a cross-sectional view, and (b) is a perspective view.

FIG. 2 is a process chart for explaining another example of a method for producing the microorganism carrier of the present invention. (A) is a superimposing step (cross-sectional view), (B) is a spirally winding step (cross-sectional view),
(C) is a welding step (cross-sectional view), (D) is the obtained microorganism carrier, (a) is a cross-sectional view, and (b) is a perspective view.

FIG. 3 is a schematic sectional view of a sewage treatment tank according to an example of the present invention.

[Explanation of symbols]

1: sheet-shaped water-permeable member 2: sheet-shaped water-permeable member P 3: sheet-shaped water-permeable member Q 4: welding machine 5: support base 10: microorganism carrier 21: sewage purification tank 22: anaerobic filter bed tank 23: anaerobic filter bed Tank 24: Aerobic filter bed tank 25: Treatment water tank 26: Disinfection tank 27: Blower 28: Aeration member 29: Sludge discharge member 30: Return pipe 31: Manhole cover 32: Inlet 33: Anaerobic filter bed 34: Anaerobic filter Floor 35: Aerobic filter bed 36: Outlet

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Shinji Fujita 1250 Shimoedori, Shimodate-shi, Ibaraki Pref.Hitachi Kasei Kogyo Co., Ltd. (72) Inventor, Yuji Koizumi, Hitachi Chemical Co., Ltd.Yuji Koizumi, 1250, Shimoe-ren, Oji, Shimodate, Ibaraki Pref. 1250 F-term in the Yuki Plant of Hitachi Chemical Co., Ltd.F-term (reference)

Claims (7)

[Claims] 1. A microorganism carrier in which a sheet-like water-permeable member is spirally wound. 2. The microorganism carrier according to claim 1, wherein the sheet-like water-permeable member is formed by stacking two different types of sheet-like water-permeable members. 3. The microorganism carrier according to claim 2, wherein one of the two different sheet-like water-permeable members is intended to adhere and retain microorganisms, and the other is to prevent deformation. 4. The sheet-like water-permeable member is one of a sheet-like mesh, a fiber material and a porous material.
3. The microbial carrier according to any of 3). 5. A sheet-shaped water-permeable member having one side as a core and spirally wound in the direction of the opposite side to a predetermined thickness until a predetermined thickness is reached. A method for producing a microbial carrier, characterized in that the free end of the sheet-like water-permeable member is fixed to a winding surface by separating the sheet-like water-permeable member. 6. A method for producing a microorganism carrier, wherein the spiral product obtained by the production method according to claim 4 or 5 is further cut into an appropriate length. 7. A sewage purification tank comprising the microorganism carrier according to claim 1 in a tank.