JP3383501B2 - Biological water treatment equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biological water treatment apparatus for biologically treating water to be treated containing a nitrogen component and an organic substance, and more specifically, a long water bundle comprising a bundle of long single fibers. A biological water treatment in which a fiber bundle is placed as a microbial support material in a treatment tank to support microorganisms on the support material and biologically treat the water to be treated under aerobic or anaerobic conditions. It relates to the device.

[0002]

2. Description of the Prior Art Organic substances such as BOD and COD components in waste water are removed, or nitrogen components such as organic nitrogen, ammoniacal nitrogen, nitrate nitrogen and nitrite nitrogen are nitrified or denitrified. An immersion filter bed biological water treatment device is used as one of the water treatment devices to be removed. The immersion filter bed type biological water treatment device is a tank filled with a microorganism supporting material so as to be immersed in the water to be treated, and the function of aerobic or anaerobic microorganisms grown on the surface of the microorganism supporting material. This biologically decomposes and removes substrates such as organic substances and nitrogen components contained in the water to be treated. As the microorganism-supporting material to be filled in the treatment tank, generally, a porous artificial stone such as gravel, crushed stone, or calcined aggregate, an inorganic substance such as anthracite, and a honeycomb-shaped molded article made of plastic are used. There is.

As one of the immersion filter bed type biological water treatment apparatuses, JP-A-4-281895 discloses that long filaments are assembled to form a filament bundle, and the filament bundle is loaded with microorganisms. An organism characterized in that it is arranged as a material in the treatment tank so as to meander vertically between the upper and lower portions of the treatment tank, and the upper and lower turning portions thereof are substantially fixed to a support. We propose a biological water treatment system. In the immersion filter bed type biological water treatment apparatus disclosed in the above-mentioned publication, in the case of a treatment tank having a rectangular horizontal cross section, as shown in FIG.
The support 72 of the above comprises an upper support rod 74 and a lower support rod 76 extending in parallel and horizontally in the upper and lower portions of the processing tank 78, respectively, and the long fiber bundle 70 includes the upper support rod 74 and the lower support rod 76. It is arranged so as to be installed between them. To further explain, each long fiber bundle 70 is hooked around the upper support rod 74, is lowered toward the lower support rod 76, is then hooked around the lower support rod 76, and then is hooked on the upper support rod. The upper support rod 74 and the lower support rod 76 meander vertically by an arrangement method in which the upper support rod 74 is lifted up to 74 and is hooked around the upper support rod 74 again. Further, the turning portion around which the upper support rod 74 and the lower support rod 76 are wound is hooked or substantially fixed in various ways. In FIG. 7, reference numeral 78 is a rectangular treatment tank, 80 is an inlet pipe for water to be treated, 82 is a drain pipe for treated water, and 84 is an air inlet pipe.

This biological water treatment apparatus using long fiber bundles as a microorganism-supporting material has a remarkably higher concentration of microorganisms per unit volume of the treatment tank than in the case where a filamentous or string-like microorganism-supporting material is also meandered. In addition, the porosity is large and the surface area of the microorganism-supporting material per unit flow rate of the water to be treated is remarkably large as compared with the case where a granular microorganism-supporting material is used. Therefore, it is rare that the microorganism supporting material catches SS (solid suspended substance) in the water to be treated and causes clogging, and even if clogging occurs, it can be washed and removed very easily. Therefore, it can be evaluated that it has extremely preferable performance as a biological water treatment apparatus of the immersion filter type.

[0005]

By the way, since the treatment tank of a large biological water treatment apparatus is made of concrete, it is often a cubic tank or a rectangular parallelepiped tank, but a treatment tank of a small apparatus is usually economical. For the reason, it is often made of a steel plate and formed in a cylindrical shape so that a processing tank having the same capacity can be formed with a thin wall thickness. However, in the biological water treatment device disclosed in the above-mentioned publication, when a cylindrical tank is used as the treatment tank, the horizontal cross section is circular, and therefore, when the long fiber bundles are arranged in the above-described arrangement, long fibers are arranged. the length of the bundle, as shown in FIG. 8, a path P _1, P _2, P ₃ along a radius perpendicular from the path P ₀ to dispose along a central portion of the processing tank in diameter path P ₀ It becomes shorter as it is gradually separated from the path P ₀ . Therefore, it is necessary to manufacture long fiber bundles having lengths corresponding to the disposition paths of different lengths, which complicates the manufacturing process of the long fiber bundles and increases the manufacturing cost of the long fiber bundles. there were. Further, also when disposing the long fiber bundle, the disposition paths P ₀ , P ₁ , P ₂ , P ₃
Therefore, it is necessary to attach long fiber bundles having different lengths to each other, which makes the attachment work complicated.

Further, when the long fiber bundles are arranged in the above-mentioned arrangement in the cylindrical processing tank, it is difficult to make the packing density of the long fiber bundles in the processing tank uniform. There is also a problem that the treated water tends to flow in one direction and uniform treatment is difficult.

On the other hand, a small biological water treatment apparatus having a cylindrical treatment tank is used for economical treatment of small-scale wastewater.
In particular, there is an increasing demand from the viewpoint of environmental protection. But,
As long as the above-mentioned problems exist in the cylindrical treatment tank, it is impossible to use the cylindrical treatment tank to meet the demand for economical biological water treatment. In view of the above circumstances, an object of the present invention is to provide a biological water treatment apparatus which is suitable for a cylindrical treatment tank, and in which long fiber bundles used as a microorganism supporting material can be easily arranged. is there.

[0008]

In order to achieve the above object, the biological water treatment apparatus according to the present invention is a treatment tank in which a long fiber bundle formed by bundling a plurality of long single fibers is used as a microorganism supporting material. In a biological water treatment device of the immersion filter bed type, which is disposed inside the tank and biologically treats the water to be treated which has been passed through the treatment tank with the microorganisms supported on the surface of the long filaments, Is composed of long fiber bundles arranged in the treatment tank so as to meander vertically between the upper portion and the lower portion of the treatment tank radially from the center of the treatment tank toward the tank wall. I am trying.

The present invention can be applied without restriction on the cross-sectional shape of the treatment tank, but is particularly suitable for a biological water treatment apparatus having a treatment tank formed of a cylindrical container. In the present invention, regarding the disposition of the long fiber bundle, the long fiber bundle is disposed in the processing tank radially from the central portion of the processing tank toward the tank wall while meandering vertically between the upper part and the lower part of the processing tank. As long as it is done, there are no restrictions. As an arrangement method, for example, in the case of applying to a cylindrical treatment tank, a plurality of upper circular rings having mutually different diameters are arranged concentrically and horizontally as a support on the upper portion of the treatment tank. At the bottom of the tank, arrange the lower ring in a position such that the lower ring is located between the upper ring and the next upper ring of smaller diameter, and the upper ring and lower ring of the support A long fiber bundle may be hung between the same as in the above publication. In this case, the interval between the rings in the upper and lower portions of the processing tank is typically 100 to 300 mm, preferably 10 mm.
It is preferably 0 to 200 mm, and the lower circular ring is preferably located exactly in the middle between the upper circular rings adjacent to each other.

Further, there is no restriction on the method of fixing the turning portion of the long fiber bundle on the upper and lower circular rings, and for example, the long fiber bundle may be wound around the circular ring once or a plurality of times to be wound and fixed. Alternatively, the long fiber bundle may be fixed to the ring with a plastic insulock or the like. Further, the long fiber bundle may be fixed to the ring with a U-shaped bolt so that the turning portion does not move along the ring, or a ring may be attached to the ring and the long fiber bundle may be attached once or plural times to the ring. You may fix it by turning it around.
The shape of the support provided on the upper and lower parts of the processing tank for hanging the long fiber bundle and for locking and fixing the rotating part of the long fiber bundle is such that the long fiber bundle is at the center of the processing tank. There is no limitation as long as it can meander vertically between the upper part and the lower part of the processing tank radially toward the tank wall, and the above-described upper and lower circular rings are one example, for example, a regular polygonal shape. It may be a ring.

Further, when the long fiber bundles are radially arranged while meandering vertically from the central portion of the treatment layer toward the tank wall, the packing density becomes dense in the central portion and becomes sparse around the tank wall. Therefore, when the treatment layer has a large diameter, another long fiber bundle is newly provided from the middle portion of the treatment layer between the long fiber bundles arranged from the center of the treatment layer toward the tank wall and the long fiber bundle. Similarly, they are arranged in a radial pattern while meandering vertically toward the wall. Thereby, the packing density can be made uniform. Further, when arranging the long fiber bundles which meander vertically and radially extend as described above, the distance between the adjacent long fiber bundles and the long fiber bundles in the horizontal plane is the outer peripheral portion even in the central portion of the processing tank. Also in 100 to 30
The long fiber bundle is arranged so as to be in the range of 0 mm, preferably in the range of 100 to 200 mm.

The long fiber bundle used in the biological water treatment apparatus of the present invention typically has a large number of long monofilaments having a diameter of 10 to 100 μm, preferably 40 to 80 μm, for example, 3
It is a bundle of 50,000 to 150,000 bundles. The material of the long monofilament is not particularly limited, but is preferably a material having acid resistance, alkali resistance, oxidation resistance, and reduction resistance, such as acrylic, polyester, polyamide, nylon. It is a synthetic fiber such as a fiber-based or polyolefin-based fiber.

The amount of long fiber bundles to be filled in the treatment tank varies depending on the water quality of the water to be treated and is not particularly limited, but generally, in terms of weight, the dry weight per volume of 1 m ³ in the tank is used. Approximately 5 to 50 kg, with a porosity of 9 in volume ratio conversion
It is often preferred that it is 5 to 99%. The porosity is a value obtained by the formula of porosity = {(volume of treatment tank-filling volume of long fiber bundle) / volume of treatment layer} × 100, and filling volume of long fiber bundle is long. It can be determined from the filling weight of the fiber bundle and the specific gravity.

By using the long fiber bundle filled and arranged as described above as a microorganism supporting material, the amount of microorganisms supported per unit volume of the treatment tank can be increased as compared with the case where a filamentous or string-like microorganism supporting material is used. It is possible to secure a very large amount, and the porosity is 2 to 3 times, and the surface area of the microorganism supporting material with respect to the water to be treated is 10 to 50 times larger than when using a granular microorganism supporting material. Clogging is less likely to occur, and the amount of water to be treated per unit volume of the treatment tank increases.

In a preferred embodiment of the present invention, a plurality of mesh tube stages, in which mesh tubes are arranged in parallel with each other, are stacked in parallel between the air diffuser provided at the bottom of the treatment tank and the microorganism supporting material. It is characterized in that it has a dispersion portion formed. The mesh tube has a shape in which a relatively large mesh made of plastic mesh is rolled into a cylindrical shape or a square tube shape to form a tubular shape, and there is no limitation on the manufacturing method thereof. When arranging the mesh tubes, the mesh tubes do not necessarily have to be adjacent to each other.
By arranging the mesh tube stages in the shape of a cross at a height of 0.5 to 1.0 m to form a dispersion part, coarse bubbles of the gas flowing out from the diffuser pipe are subdivided by the mesh pipe, and inside the treatment tank. It is possible to evenly disperse the gas in a uniform manner and to uniformly supply the microorganisms.

When the treatment tank is formed in a cylindrical shape, it is necessary to adjust the lengths of the mesh tubes by adjusting the lengths of the mesh tubes in order to arrange the long mesh tubes in parallel and horizontally in the cylindrical treatment tank. There is. In this case, since the stacking of the mesh tubes is a very complicated and time-consuming task, for example, the mesh tube part in which the mesh tubes are stacked and the filling part in which the filler material is filled around the mesh tube part are dispersed. The parts can also be configured. To this end, first, the mesh tubes are arranged in a square shape inscribed in the treatment tank, and the mesh tube sections are stacked in the shape of a cross to form the mesh tube portion. Next, in the half-moon-shaped space between the tank wall of the processing tank and the stacked mesh tubes, the mesh tube having a length of about 10 to 20 cm, a molded plastic filler having a diameter of about 10 cm, or 10 to 20 cm on each side. The tetrahedral mesh-shaped filling material is randomly filled to form a filling portion.

Further, in a particularly preferred embodiment of the present invention, a support for constructing the long fiber bundle is assembled outside the treatment tank, and the long fiber bundle is further provided on the support to form a microbial carrier in advance. Prepare and load the microbial carrier into the treatment tank. By doing so, it is possible to significantly save manpower and time as compared with the method of assembling the support in the processing tank and then constructing the long fiber bundle.

The gas generated by the treatment with the microorganisms adheres to the surface of the long filaments or is captured by the long fiber bundles, accumulates in the long fiber bundles, and is generated by the microorganisms carried on the long fiber bundles. It inhibits the treatment by microorganisms by giving substance inhibition or impairing contact with the substrate. By the way, in biological treatment with aerobic microorganisms, oxygen-containing gas such as air is fed into the treatment tank, so the long fiber bundles vibrate due to collision with air, which causes the accumulated gas to dissociate. However, in the anaerobic microbial treatment, since air is not introduced into the treatment tank, product inhibition occurs as described above. Further, in the treatment with anaerobic microorganisms, since there is no stirring action by air, the substrate tends to be maintained at a high concentration in the lower part of the treatment tank, and the microorganisms are subjected to substrate inhibition.

Therefore, a further preferred embodiment of the present invention is provided with a treatment tank of a closed type and a gas circulation system for supplying gas sucked at the upper portion of the treatment tank from the lower portion of the treatment tank, so that anaerobic microorganisms can be lengthened. The feature is that they are supported on single fibers. In the present embodiment, a part of the gas generated in the treatment tank is re-introduced into the treatment tank, the long-fiber bundle is vibrated by the introduced gas, and the water to be treated is agitated to obtain the surface of the long-fiber bundle. Removes the generated gas adhering to
By dispersing the substrate in the water to be treated, it is possible to prevent product inhibition and substrate inhibition from occurring.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 Hereinafter, an embodiment in the case of using a cylindrical container as a processing tank will be described, and an embodiment of the present invention will be described concretely and in detail with reference to the accompanying drawings. . FIG. 1 is a schematic cross-sectional view showing the configuration of an embodiment of the biological water treatment apparatus according to the present invention, FIG. 2 is a perspective view of a microorganism carrier, FIG. 3 is a perspective view of a support, and FIG. 4 is a long fiber bundle. FIG. 5 is a schematic perspective view showing the configuration of a mesh tube. The biological water treatment apparatus 10 of the present embodiment is an apparatus for subjecting water to be treated to biological treatment by aerobic microorganisms, and as shown in FIG. 1, a cylindrical treatment tank 12 and a treatment tank 12 It is provided with a microbial carrier 14 arranged therein, and an air dispersion unit 16 provided below the microbial carrier 14. Further, a sprinkler pipe 18 for introducing water to be treated and a diffuser pipe 20 for introducing air are connected to the bottom of the treatment tank 12, and a discharge pipe 22 and an exhaust pipe 24 of treated water are provided on the upper portion of the treatment tank 12. It is connected.

The microbial carrier 14 is, as shown in FIG.
It is composed of a support 26 and a large number of long fiber bundles 28 laid on the support 26. As shown in FIG. 3, the support 26 includes a support column 30, six upper horizontal beams 32 radially extending from the upper end of the support column 30 at intervals of about 60 °, and a large number of concentric members supported by the upper horizontal beam 32 (however, 2 to 4, only four are simply shown).
6 lower horizontal beams 36 extending radially from the lower end of the upper horizontal beam 32 in the same direction as the upper horizontal beam 32, and a large number of concentric members supported by the lower horizontal beam 36 (however, only four are simply shown in FIGS. 2 to 4)
The lower circular rings 38A to 38D, and the connecting member 40 that connects the tips of the upper horizontal beams 32 and the corresponding tips of the lower horizontal beams 36 to reinforce the support 26.

Each of the upper ring 34 and the lower ring 38 is
As shown in FIG. 3, when viewed from above the support 26, the outermost lower circular rings 38D are the outermost upper circular rings 34D and the inner circular rings 34C when they are arranged concentrically at intervals of 150 mm. It is arranged so that it is located exactly in the middle of. That is, if the diameter of the outermost upper ring 34D is D ₁ , the diameter of the inner ring 34C is D ₂ and the diameter of the outermost lower ring 38D is D ₃ , then D ₃ = (D ₁ + D ₂ ) × 1
In the following, the upper ring 34 and the lower ring 38 are related.
Are arranged in a similar relationship toward the inside (see FIG. 4). There are no particular restrictions on the materials of the columns 30, the upper horizontal beam 32, the upper circular ring 34, the lower horizontal beam 36, the lower circular ring 38, and the connecting member 40 that make up the support 26, and they are, for example, solid rod-shaped bodies or hollow pipe materials. The material is not particularly limited as long as it is a mold material, and stainless steel or the like can be preferably used.

As shown in FIG. 3, the large number of long fiber bundles 28 are radially arranged from the center of the processing tank 12 toward the tank wall of the processing tank 12. The arrangement of the long fiber bundles 28 will be described in more detail with reference to FIG. Note that, in FIG. 4, for convenience, only half of the long fiber bundle of the microorganism carrier 14 viewed from above is illustrated, and the upper and lower horizontal beams 34 and 38 are omitted. In FIG. 4, six long fiber bundles 4 having a long length are shown.
2 descends from the upper end of the column 30, is hooked around the lower ring 38A, then rises, is hooked around the upper ring 34A, is lowered again, and is wound around the lower ring 38B. The upper ring 34D is hooked around the upper ring 34D in the same manner as described above, and is stopped there. In addition, the twelve long fiber bundles 44 having a shorter length than the long fiber bundle 42 are the upper ring 34A.
Then, it is arranged in the same manner as the long fiber bundle 42, and finally, it is hooked around the upper circular ring 34D, and is stopped there. Furthermore, 12 long fiber bundles 4 shorter than the long fiber bundles 44
6 descends from the upper circular ring 34B, and is arranged in the same manner as the long fiber bundles 42 and 44, and finally, it is hooked around the upper circular ring 34D and becomes the end there.

In FIG. 4, by arranging 30 long fiber bundles 28 radially, the angle θ on the horizontal plane formed by adjacent long fiber bundles 28 is about 9 °, and FIG. As can be seen from the above, the long fiber bundles 28 are almost uniformly filled in the processing tank 12. The arrangement method of the long fiber bundles 28 is not limited to this, and for example, the long fiber bundles 44 and the long fiber bundles 4 that are adjacent to each other may be used.
It is also possible to further arrange the same as the above-mentioned long fiber bundle 46 between the same and the above.

As shown in FIG. 1, the dispersion section 16 provided under the microorganism carrier 14 has a mesh tube section 48 in which cylindrical mesh tubes are stacked, and between the mesh tube section 48 and the treatment tank 12. It is composed of a filling portion 50 in which a plastic filler as described below is filled in a gap having a half-moon cross section. The cylindrical mesh tube 52 that constitutes the mesh tube portion 48 has a different mesh shape, as shown in FIGS. 5A to 5D, respectively.
It has a shape in which a relatively large mesh made of a plastic mesh is rolled into a tubular shape or a rectangular tubular shape to form a tubular shape.

The mesh tube portion 48 has a square shape which is inscribed in the processing tank 12 by arranging cylindrical mesh tubes 52 of the same length in parallel on a grid plate 51 provided in the lower portion of the processing tank 12 in parallel. A mesh tube stage is formed, and then the mesh tube stages are stacked in a plurality of rows in a girder pattern to form a stack with a height of about 0.7 m. The filling section 50 is configured by filling a mesh-shaped regular tetrahedron whose one side has a length of 10 to 20 cm. Instead of the mesh regular tetrahedron, a small piece such as a cylindrical mesh tube having a smaller diameter and a shorter length than the cylindrical mesh tube 52 or a molded plastic material having a diameter of about 10 cm may be used as the filler.

As shown in FIG. 1, a plurality of air diffusing tubes 20 branch from a header (not shown) under the dispersing section 16 and are evenly arranged along the floor of the processing tank 12. The air diffuser 20 is provided with an air nozzle (not shown) so as to eject air downward.
Further, a sprinkler pipe 18 is provided at the bottom of the treatment tank 12,
The water to be treated is dispersed and introduced. On the other hand, a trough 54 is formed in the upper part of the treatment tank 12 along the circumference of the treatment tank 12, and a discharge pipe 22 is connected to the trough 54 to discharge the treated water to the outside.

The water to be treated is introduced from the sprinkling pipe 18 into the treatment tank 12, is dispersed by the air in the dispersion section 16 and rises in the treatment tank 12 with a substantially uniform distribution, while the long fiber bundle 28
Contact with. When the water to be treated comes into contact with the long fiber bundle 28, organic substances in the water to be treated, nitrogen compounds such as ammonia, etc.
The activity of the aerobic microorganisms grown on the surface of each single fiber of the long fiber bundle 28 biologically oxidizes and decomposes the water, and the purification of the water to be treated proceeds. The treated water purified while rising in the treatment tank 12 overflows into the trough 54 and is discharged from the discharge pipe 22 to the outside of the tank.

On the other hand, the processing tank 1 introduced from the air diffuser 20
The air introduced into 2 is subdivided by the dispersion unit 16. The subdivided air is evenly distributed to supply oxygen to the microorganisms and promote their activity. Further, the subdivided bubbles collide with the long fiber bundle 28, and remove fine gas bubbles, solid particles, and the like that are attached to the surface of the long fiber bundle 28 and are generated as a result of biological oxidation and decomposition. Also plays a role.

Assembling the support 26 outside the processing tank 12,
Further, the long fiber bundles 28 are laid on the support 26 in the above-mentioned arrangement to pre-form the microorganism carrier 14 as shown in FIG.
If it is installed in the processing tank 12, the processing tank 1
Compared with assembling the support 26 in the two and then arranging the long fiber bundles 28, a great deal of manpower and time can be saved.

Example 2 This example is an example in which the biological water treatment apparatus according to the present invention is applied to anaerobic microbial treatment, specifically, methane fermentation treatment and denitrification treatment, and FIG. 5 is a schematic cross-sectional view showing the configuration of the biological water treatment apparatus of Example 2. FIG. As shown in FIG. 6, the biological water treatment apparatus 60 of the present embodiment is a hermetically sealed container (in this embodiment, the container is also cylindrical) that is shielded from the outside atmosphere to retain anaerobic microorganisms. The formed processing tank 62 and a gas circulation system 64 for sucking gas from the upper portion of the processing tank 62 and feeding the sucked gas from the lower portion of the tank.
The configuration is the same as that of the first embodiment except that The same parts as those shown in FIGS. 1 to 4 among the parts and parts shown in FIG.

The gas circulation system 64 sucks methane gas, carbon dioxide, and nitrogen gas generated by the biological treatment of the water to be treated by anaerobic microorganisms from the upper portion of the treatment tank 62 and sends them to the lower portion of the treatment tank 62 again. A circulation pipe 66, which is provided for the purpose of connecting the exhaust pipe 24 at the top of the treatment tank 62 and the diffuser pipe 20 at the bottom of the treatment tank 62, and a gas circulation blower 68 provided at the circulation pipe 66. It consists of and.

In this embodiment, the gas is circulated and again fed into the treatment tank 62, so that the gas having the same function as the air fed in the biological treatment by the aerobic microorganisms is fed. Therefore, the microorganisms do not undergo the substrate inhibition and product inhibition as described above, and the treatment proceeds rapidly. Of the gases such as methane gas and carbon dioxide generated by the biological treatment, gases other than those circulated through the circulation pipe 66 are discharged outside the tank together with the treated water through the discharge pipe 22. To be done.
If the gas is corrosive or toxic, such as hydrogen sulfide, or water that generates water, it is desirable to provide a desulfurization device or a dehumidification device in the circulation pipe 66 for detoxification and dehumidification. . Also, the blower 68 is preferably corrosion resistant.

In the first and second embodiments described above, the present invention has been described by taking as an example the case where the water to be treated flows in the treatment tank in an ascending flow. The biological water treatment apparatus according to the present invention can be configured so as to flow in the treatment tank. Further, the shape of the support is not limited to the structure of the support 26 shown in the first embodiment. Further, although the case where the container has a cylindrical shape has been described as an example, it goes without saying that the present invention can be applied to a cubic tank or a rectangular parallelepiped tank.

[0035]

According to the present invention, the long fiber bundles are arranged in the treatment tank in a radial direction from the central portion of the treatment tank toward the tank wall while meandering vertically between the upper and lower portions of the treatment tank. Even if the container is cylindrical, it is easy to dispose long fiber bundles and the packing density of long fiber bundles is uniform. We have realized an equipment with a processing tank that is optimal for the processing equipment. Since the long fiber bundles are arranged in the treatment tank with a uniform packing density, even if the treatment tank is a cylindrical treatment tank, it prevents one-way flow of the water to be treated, resulting in high biological performance. A water treatment device can be realized.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing the configuration of a biological water treatment apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a microorganism carrier.

FIG. 3 is a perspective view of a support.

FIG. 4 is a diagram showing an arrangement of long fiber bundles.

5 (a) to 5 (d) are perspective views of a cylindrical mesh tube, respectively.

FIG. 6 is a schematic cross-sectional view showing the configuration of Example 2 of the biological water treatment apparatus according to the present invention.

FIG. 7 is a perspective view showing a configuration of a conventional biological water treatment device.

FIG. 8 is a diagram for explaining a problem in a case where long fiber bundles are arranged in a cylindrical processing tank in the same arrangement as the conventional one.

[Explanation of symbols]

10 Example 1 of biological water treatment apparatus according to the present invention 12 treatment tanks 14 Microorganism carrier 16 Air dispersion unit 18 Sprinkling pipe 20 Air diffuser 22 Discharge pipe 24 exhaust pipe 26 Support 28 Long fiber bundle 30 props 32 Upper horizontal beam 34 Upper ring 36 Lower horizontal beam 38 Lower ring 40 Connection member 42,44,46 Long fiber bundle 48 mesh tube 50 filling section 52 Cylindrical mesh tube 54 trough 60 Example 2 of biological water treatment apparatus according to the present invention 62 treatment tank 64 gas circulation system 66 Circulation pipe 68 gas circulation blower

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-4-281895 (JP, A) JP-A-2-227189 (JP, A) JP-A-3-27138 (JP, A) Actual development Sho-63- 28198 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) C02F 3/10 C02F 3/14-3/34

Claims (3)

(57) [Claims] 1. A long fiber bundle formed by bundling a large number of long monofilaments as a microorganism supporting material is disposed in a treatment tank, and the water to be treated passed through the treatment tank is carried on the surface of the long monofilament. In an immersion filter bed biological water treatment device that biologically treats with the microorganisms that have been treated, the treatment tank is formed of a cylindrical container, and the support that supports the microorganism supporting material is concentric with the upper portion of the treatment tank.
Upper circles with different diameters arranged horizontally
A ring, one upper ring and the inside of the next smaller diameter
Concentric water in the lower part of the treatment tank so that it is located between the step ring and
Earnestly and a deployed lower ring, microbial support material, the upper ring and the lower circle of the support so as to meander under the top from the center of the treatment tank toward the tank wall radially
A biological water treatment device, which is suspended between a ring and the ring . 2. A dispersion part, which is formed by stacking a plurality of mesh tube stages in which mesh tubes are arranged in parallel to each other between the air diffuser provided at the bottom of the treatment tank and the microorganism-supporting material, in a grid pattern. The biological water treatment device according to claim 1 , wherein the biological water treatment device is provided. 3. A treatment tank configured as a hermetically sealed type, and a gas circulation system for feeding gas sucked at the upper portion of the treatment tank from the lower portion of the treatment tank so that anaerobic microorganisms are supported on the microorganism supporting material. The biological water treatment device according to claim 1 or 2, characterized in that: