Sewage treatment unit, purification device, and purification method

Abstract

In a wastewater treatment unit having a structure in which a microorganism-holding carrier is supported by a support material, the purification function of this carrier is efficiently utilized. [Solution] A wastewater treatment unit 100 for carrying out microbial reaction treatment on wastewater includes a carrier 110 capable of retaining microorganisms, and a support material 120 having a plurality of openings 122 formed therein for supporting the carrier 110 from below, and is configured so that the carrier 110 can be placed between the upper and lower support materials 120 when the support materials 120 are stacked. The carrier 110 has a plurality of through holes 113 formed therein that penetrate in the thickness direction.

Description

Technical Field

[0001] The present invention relates to a sewage treatment unit used for purifying sewage by microbial reaction. The present invention also relates to a purification device including this sewage treatment unit in a microbial reaction tank where sewage is sprinkled, and a purification method using this sewage treatment unit.

Background Art

[0002] Conventionally, there are known the DHS (Downflow Hanging Sponge) method of sprinkling sewage into a treatment tank filled with a large number of carriers holding microorganisms and aerobically purifying the sewage by the decomposition function of the microorganisms held by the carriers, and a purification device (DHS reactor) for carrying out this method.

[0003] The applicant of the present application has proposed a technique for enabling uniform supply of sewage to the entire treatment tank even when the flow rate of sewage supplied to the purification device is reduced (Patent Document 1). In Patent Document 1, for example, a dispersion member (spray plate) is arranged at a position between the treatment tank and the sprinkling device where the sewage falling from the sprinkling device collides, and the sewage is dispersed by this dispersion member to widely disperse the sewage to the treatment tank.

[0004] Further, in Patent Document 2, a microbial immobilization carrier has been proposed in which a plurality of carriers (porous bodies) for immobilizing microorganisms are inserted into a frame having a honeycomb structure, for example, so that these carriers can be regularly arranged in the frame and a plurality of frames filled with these carriers can be stacked in multiple stages.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] By the way, in the microbial immobilization carrier of Patent Document 2, since the carriers are partitioned by a frame, there is a structural problem that the flow of sewage between adjacent carriers is inhibited by the frame. In such a structure where it is difficult for sewage to leach from one carrier to another, it becomes difficult to uniformly supply sewage to the entire carrier held by the frame, and there is a problem that the purification function of the carrier cannot be utilized to the maximum extent. In addition, in the structure of Patent Document 2, it is necessary to pack each carrier into the frame one by one, which also causes a problem that the labor required at the start of use or replacement of the carrier increases.

[0007] Furthermore, in sewage purification by microbial reaction, it is known that solids accumulate on the carrier as the sewage contains solids or solids are generated by the reaction between the microorganisms held on the carrier in the treatment tank and the sewage. Here, in the microbial immobilization carrier of Patent Document 2, if solids accumulate on the upper surface portion of the carrier, the introduction of sewage into the carrier is inhibited by the solids, causing the sewage to slide sideways on the carrier, and ultimately there is a concern that the sewage will fall downward from the outside of the frame or be guided downward along the frame between the carriers without entering the carrier. Also in such a case, it becomes difficult to utilize the purification function of the carrier to the maximum extent.

[0008] Therefore, the main object of the present invention is to provide a technique capable of efficiently utilizing the purification function of a carrier in a sewage treatment unit having a structure in which a microbial holding carrier is supported by a support material.

Means for Solving the Problems

[0009] As a result of intensive studies on means for solving the problems of the above-mentioned conventional inventions, the inventor of the present invention has found that by supporting a carrier capable of holding microorganisms from the lower surface side by a support material and forming a plurality of through holes along the thickness direction of the carrier, the purification function of the carrier can be efficiently utilized. And, based on the above findings, the inventor has conceived that the problems of the conventional inventions can be solved and has completed the present invention. Specifically described, the present invention has the following configurations or steps.

[0010] A first aspect of the present invention relates to a sewage treatment unit 100. The sewage treatment unit 100 is used for performing a microbial reaction treatment on sewage. The sewage treatment unit 100 is assumed to be used by arranging a plurality of them in the left-right direction or stacking a plurality of them in the up-down direction. However, the first aspect of the present invention relates to this sewage treatment unit 100 alone. The sewage treatment unit 100 includes a carrier 110 and a support material 120. The carrier 110 is capable of holding microorganisms and is basically composed of a porous body such as a sponge. The support material 120 has a plurality of openings 122 formed therein and is a member used for supporting the carrier 110 from its lower surface side. The support materials 120 can be stacked in the up-down direction. Each support material 120 is configured such that the carrier 110 can be disposed between the upper and lower support materials 120 in a state where a plurality of them are stacked. Further, the carrier 110 has a plurality of through holes 113 penetrating in its thickness direction.

[0011] As described above, by supporting the carrier 110 from the lower surface side by the support member 120, the sewage is likely to diffuse in the left - right direction of the carrier 110. Also, since it is only necessary to place the carrier 110, which spreads flat, for example, on the support member 120, the operation of arranging the carrier 110 on the support member 120 becomes easy when the use disclosure or replacement of the carrier 110 is carried out. Further, by forming the through - holes 113 in the carrier 110, the surface area of the carrier 110 increases and the flow of air and water is improved, so that the reaction efficiency of the microorganisms held in the carrier 110 is enhanced. Furthermore, even when solids are deposited on the upper surface side of the carrier 110, since the through - holes 113 are formed in the carrier 110, the sewage is likely to be introduced into the carrier 110. Therefore, according to the sewage treatment unit 100 according to the present invention, the purification function of the carrier 110 can be efficiently utilized.

[0012] In the sewage treatment unit 100 according to the present invention, in a state where the carrier 110 is arranged on the support member 120, it is preferable that the through - holes 113 of the carrier 110 communicate with the openings 122 of the support member 120. That is, the fact that the through - holes 113 and the openings 122 “communicate” means that the positions of the through - holes 113 of the carrier 110 and the openings 122 of the support member 120 overlap in a plan view. In this way, by making the through - holes 113 and the openings 122 communicate in the vertical direction in a state where the carrier 110 is arranged on the support member 120, the flow of air and water can be ensured.

[0013] In the sewage treatment unit 100 according to the present invention, it is preferable that a plurality of convex portions 115 surrounded by grooves 114 are formed on the lower surface side of the carrier 110. In this case, the convex portions 115 of the carrier 110 are preferably fitted into the openings 122 of the support member 120. In this way, by forming the convex portions 115 that fit into the openings 122 of the support member 120 on the lower surface side of the carrier 110, it becomes easy to position the carrier 110 when placing it on the support member 120, and it becomes difficult for the carrier 110 to be displaced on the support member 120, improving the stability.

[0014] The sewage treatment unit 100 according to the present invention is preferably configured such that in a state where the convex portion 115 of the carrier 110 is fitted into the opening 122 of the support material 120, the apex (lower end side) of the convex portion 115 protrudes from the lower surface of the support material 120. In this way, since the apex on the lower end side of the convex portion 115 of the carrier 110 is configured to protrude downward from the support material 120, the sewage seeping out from the lower end of the carrier 110 is likely to land on another carrier 110 further below. That is, when the carrier 110 is simply placed on the frame portion 121 of the support material 120 (when a part of the carrier 110 does not protrude from the lower surface of the support material 120), there is a concern that the sewage seeping out from the lower end of the carrier 110 will land on a place where the carrier 110 does not exist along the frame portion 121 of the support material 120. In this regard, by configuring as described above, sewage can be effectively guided from the upper carrier 110 to the lower carrier 110.

[0015] It is preferable that the through hole 113 described above is formed in at least one or more of the plurality of convex portions 115 of the carrier 110 in the sewage treatment unit 100 according to the present invention. In this way, by forming the through hole 113 in the convex portion 115, the flow of air and water can be further improved.

[0016] In the sewage treatment unit 100 according to the present invention, the support member 120 preferably has a plurality of legs 123 extending downward therefrom and a leg receiving portion 124 for placing the legs 123 of another support member 120 stacked thereon. In this case, it is preferable that the carrier 110 is formed with a missing portion 116 so as not to contact the legs 123 of another support member 120. Thus, by providing the legs 123 and the leg receiving portion 124 on each support member 120, it becomes easier to stack a plurality of support members 120 in the vertical direction while maintaining the space between the upper and lower support members 120. Further, by forming the missing portion 116 in the carrier 110 to avoid the legs 123 of the support member 120, it is possible to suppress the liquid exuded from the carrier 110 from flowing downward along the legs 123. That is, if the liquid exuded from the carrier 110 flows downward along the legs 123, the liquid may locally concentrate only on the portion of the carrier 110 in contact with the legs 123, and there is a possibility that the purification function of the carrier 110 cannot be efficiently utilized. In this regard, such a situation can be avoided by configuring as described above.

[0017] In the sewage treatment unit 100 according to the present invention, the length of the legs 123 of the support member 120 is preferably longer than the thickness of the carrier 110. Thereby, in a state where the carrier 110 is disposed on the support member 120, a gap C can be formed between the carrier 110 and another support member 120 stacked thereon. When the carrier 110 and another support member 120 above it are in close contact, it becomes difficult to supply air such as oxygen to the carrier 110. However, by providing a gap between the carrier 110 and the support member 120, a ventilation path is formed between the upper carrier 110 and the lower carrier 110, so that air such as oxygen can be efficiently supplied to the unit 100.

[0018] In the sewage treatment unit 100 according to the present invention, the support member 120 may have a plurality of protrusions 126 that are lower in height than the leg portions 123. By providing such protrusions 126 on the support member 120, the sewage flowing along the frame portion 121 of the support member 120 can be dropped downward not from the leg portions 123 but at the locations where these protrusions 126 are formed. When the sewage flows downward along the leg portions 123 of the support member 120, the sewage concentrates around the leg portions 123, making it difficult to disperse the sewage throughout the entire carrier 110. On the other hand, by providing a plurality of protrusions 126 that are lower in height than the leg portions 123 on the lower surface of the support member 120, the sewage accumulates around the protrusions 126 and drops as it is, so that the dispersion effect of the sewage can be enhanced compared to the case where there are no protrusions 126.

[0019] In the sewage treatment unit 100 according to the present invention, the support member 120 is preferably formed in a lattice shape or a honeycomb shape. The lattice shape means a structure in which openings 122 of the same shape are regularly formed, and the shape of the openings 122 is triangular, quadrilateral, or other polygonal. Also, the honeycomb shape means a structure in which openings 122 of the same shape are regularly formed, and in particular, the shape of the openings 122 is hexagonal. By making the support member 120 in a lattice shape or a honeycomb shape in this way, the shape of the carrier 110 can be made uniform and easy to manufacture.

[0020] The second aspect of the present invention relates to a sprinkling type purification device 1 for performing a microbial reaction treatment on sewage. The purification device 1 according to the present invention includes a treatment tank 10 and a sprinkling device 20. A plurality of sewage treatment units 100 according to the first aspect described above are arranged in the treatment tank 10. The sprinkling device 20 sprinkles sewage from above the treatment tank 10.

[0021] The third aspect of the present invention relates to a sprinkling purification method for performing microbial reaction treatment on sewage. The purification method according to the present invention first supplies sewage to a treatment tank 10 (first step). A plurality of sewage treatment units 100 according to the above-described first aspect are arranged in this treatment tank 10. Further, in this treatment tank 10, a microbial reaction treatment is performed on the sewage by the sewage treatment unit 100 holding microorganisms (second step).

Effects of the Invention

[0022] According to the present invention, in a sewage treatment unit having a structure in which a microorganism-holding carrier is supported by a support material, the purification function of this carrier can be efficiently utilized.

Brief Description of the Drawings

[0023]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0024] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below, and also includes those appropriately modified by those skilled in the art within an obvious range from the following embodiments. In the specification of the present application, "A to B" means "A or more and B or less". In addition, the drawings are provided with three-dimensional coordinate axes of X, Y, and Z. The X-axis indicates the left-right direction (lateral direction) of the sewage treatment unit 100, the Y-axis direction indicates the depth direction (longitudinal direction) of the sewage treatment unit 100, and the Z-axis direction indicates the up-down direction (height direction) of the sewage treatment unit 100, respectively.

[0025] Figure 1 shows a purification device 1 according to an embodiment of the present invention. The purification device 1 of the present embodiment is used, for example, as part of an organic wastewater treatment device. The purification device 1 purifies sewage anaerobically treated by, for example, a UASB (Up-flow Anaerobic Sludge Blanket) reactor or the like by aerobic biological treatment. Specifically, the purification device 1 sprays the sewage supplied from the sewage supply pipe onto the microorganism-holding carrier filled in the treatment tank, and aerobically purifies the sewage by utilizing the decomposition function of the microorganisms held by this carrier. As shown in Figure 1, the purification device 1 includes a treatment tank 10, a water spraying device 20, a dispersion layer 30, and a water collection part 40.

[0026] The treatment tank 10 is a tank filled with a large number of carriers 110 holding microorganisms, and sewage purification is performed in this tank. The carrier 110 is guided by a support material 120 as will be described in detail later, and the combination of this carrier 110 and the support material 120 constitutes the sewage treatment unit 100. In the treatment tank 10, a plurality of these sewage treatment units 100 are arranged side by side in the left-right direction and stacked in a plurality of stages in the up-down direction.

[0027] The material of the carrier 110 is not particularly limited, and known materials can be appropriately adopted. The carrier 110 is preferably porous and water-retaining in order to increase the microbial retention density and ensure the hydraulic retention time. For example, as the carrier 110, one composed of a resin foam such as polyurethane may be used. Examples of the microorganisms retained by the carrier 110 include heterotrophic bacteria that aerobically oxidize dissolved substances, and autotrophic bacteria that aerobically oxidize ammonia, sulfur-based odors (such as hydrogen sulfide and methyl sulfide), and methane.

[0028] Further, the treatment tank 10 is installed on a pedestal (not shown). The treatment tank 10 has a bottom plate 11 on the lower end side of the internal space where the sewage treatment unit 100 is disposed, and a plurality of liquid passing holes 11a are formed in the bottom plate 11. The sewage that has passed through the sewage treatment unit 100 of the treatment tank 10 is introduced through the liquid passing holes 11a of the bottom plate 11 into the water collection part 40 provided below it.

[0029] The water spraying device 20 is arranged above the treatment tank 10 and sprays sewage onto the treatment tank 10. As the water spraying device 20, a known one can be adopted. For example, it is advisable to adopt the one disclosed in Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2018-167194). Specifically described, the water spraying device 20 receives sewage from the outflow holes of the sewage supply pipe 21 (header pipe) and sprays it. The water spraying device 20 includes a receiving member 22, a drain pipe 23, a branch pipe 24, and nozzles 25. In FIG. 1, the drain pipe 23, the branch pipe 24, and the nozzles 25 are drawn as separate bodies, but they can also be constituted by one member. The receiving member 22 is a gutter-shaped member with an open upper surface. The receiving member 22 receives the sewage flowing down from the outflow holes of the sewage supply pipe 21 and supplies the sewage to the drain pipe 23 through the insertion holes formed in the bottom surface. The drain pipe 23 is fixed to the receiving member 22 in a state of being inserted into the insertion hole on the lower surface of the receiving member 22. The branch pipe 24 is connected to the lower end of the drain pipe 23 and is configured to branch the sewage that has flowed through the drain pipe 23 toward a plurality of discharge ports while being inclined downward. In the example shown in FIG. 1, the water spraying device 20 has two discharge ports, but it is not limited thereto, and the number of discharge ports can also be three, four, or more. The nozzles 25 are for changing the flow of the sewage discharged from the discharge ports and are attached to the respective tips of the branch pipe 24. By adjusting the direction and inclination of the nozzles 25, it is possible to adjust the discharge direction of the sewage, specifically, the dripping position of the sewage.

[0030] The dispersion layer 30 is disposed between the treatment tank 10 and the water sprinkling device 20. The dispersion layer 30 receives the sewage discharged from the water sprinkling device 20, temporarily holds it, and supplies it to the treatment tank 10 while widely dispersing the sewage around the dripping position of the sewage. The dispersion layer 30 is constituted by a foam 31. The foam 31 has a porous structure in which innumerable fine pores are formed inside, and the liquid is sucked up by the capillary action of the network-like fine tubes stretched around the fine pores and the liquid is held in the fine pores. Therefore, when the sewage is dripped from above the foam 31, the sewage diffuses three-dimensionally inside the foam 31 around the dripping position. Further, when the sewage is continuously dripped onto the foam 31, the sewage already held in the foam 31 is pushed down by the newly entered sewage into the foam 31, and finally separated from the lower surface of the foam 31. In particular, when the carrier 110 in the treatment tank 10 is in contact with the lower surface of the foam 31, the sewage in the foam 31 is absorbed by the contacting carrier 110. Utilizing such a phenomenon, the dispersion layer 30 widely and uniformly disperses the sewage received from the water sprinkling device 20 with respect to the carrier 110 in the treatment tank 10.

[0031] In the present invention, the foam 31 is made of resin. The resin foam 31 is mainly obtained by a chemical foaming method in which a foaming agent and a base material are mixed, and gas is generated by the decomposition of the foaming agent to foam the base material. Examples of the resin used as the base material include polyurethane (PUR)-based resins, polyethylene (PE)-based resins, polypropylene (PP)-based resins, polystyrene (PS)-based resins, polyvinyl chloride (PVC)-based resins, and the like. Further, as the base material, one of these resins may be used, or two or more of them may be mixed and used. Among them, it is preferable to use a polyurethane-based resin as the foam 31. Examples of the polyurethane-based resin are polyether-based polyurethane resins, polyester-based polyurethane resins, polycarbonate-based polyurethane resins, silicone-based polyurethane resins, acrylic-based polyurethane resins, and modified polyurethane resins. In particular, it is preferable to adopt a polyether-based polyurethane resin. Since the foam 31 of the polyether-based polyurethane resin has high durability and shock absorbency, its shape is less likely to change even when sewage is continuously dripped for a long time, and the sewage dropped on its surface is less likely to scatter. Therefore, the sewage can be stably dispersed continuously. Further, since the molecular structure of the polyether-based polyurethane resin is relatively stable, it has resistance to sewage and microorganisms.

[0032] The water collection part 40 collects the treated water (treated liquid) that has passed through the treatment tank 10 and discharges it to the outside. As described above, a bottom plate 11 having a liquid passage hole 11a is provided at the lower end of the treatment tank 10, and the treated water passing through the liquid passage hole 11a flows into the water collection part 40. The bottom surface of the water collection part 40 is in the shape of a mortar, and a drain pipe 41 is provided at the lowest part of the bottom surface. Therefore, the treated water collected in the water collection part 40 is discharged to the outside through this drain pipe 41.

[0033] Figure 2 shows an exploded perspective view of the sewage treatment unit 100 disposed in the treatment tank 10. As shown in Figure 2, the sewage treatment unit 100 is composed of a carrier 110 and a support member 120. The carrier 110 is a porous body such as a sponge for holding microorganisms and moisture as described above. The support member 120 is a member for holding the carrier 110 from its lower surface side. The sewage treatment unit 100 is formed by placing the carrier 110 on the support member 120.

[0034] The structure of the carrier 110 is shown in the perspective view of Figure 2, the plan view of Figure 3, and the bottom view of Figure 4. In Figure 3, the end view of the carrier 110 along the line II-II is also shown. As shown in Figures 2 to 4, the carrier 110 is basically in a substantially rectangular shape that spreads in the plane direction with a certain thickness, and a plurality of through holes 113, grooves 114, and a plurality of missing parts 116 are formed therein.

[0035] Specifically, the carrier 110 is divided in the vertical direction into an upper half 111 located above and a lower half 112 located below. Note that the upper half 111 and the lower half 112 are integrated and cannot be separated. A plurality of through holes 113 penetrating from the upper surface to the lower surface are formed in the carrier 110. That is, the through holes 113 are formed across both the upper half 111 and the lower half 112 of the carrier 110. These through holes 113 are regularly arranged in the plane direction (XY direction) of the carrier 110 and are provided at equal intervals in the left-right direction (X-axis direction) and the depth direction (Y-axis direction), respectively. The through holes 113 are formed at positions corresponding to the openings 122 of the support member 120 described later, and basically, the number of through holes 113 in the carrier 110 and the number of openings 122 in the support member 120 are preferably the same.

[0036] By forming the through holes 113 in the carrier 110 in this way, the surface area of the carrier 110 is increased, and the flow of air and water is improved, so that the reaction efficiency of the microorganisms held in the carrier 110 can be enhanced. In plan view, the area of one through hole 113 is, for example, 0.2 to 4 cm 2Preferably, it is 0.3 to 2 cm 2 or particularly preferably 0.5 to 1.4 cm 2 In addition, in a plan view, the total area of the through holes 113 is preferably 2 to 20% of the total area of the carrier 110, and particularly preferably 5 to 18% or 9 to 16%.

[0037] Also, for example, as shown in FIG. 4, lattice-shaped grooves 114 are formed on the lower surface side of the carrier 110. As shown in the end views of FIGS. 2 and 3, for example, these grooves 114 are formed only in the lower half portion 112 of the carrier 110 and do not reach the upper half portion 111. In other words, the range where these grooves 114 are formed is defined as the lower half portion 112, and the range where the grooves 114 do not reach is defined as the upper half portion 111. In this way, the grooves 114 do not penetrate from the lower surface to the upper surface of the carrier 110, but are formed only from the lower surface of the carrier 110 to its middle part. Since lattice-shaped grooves 114 are formed in the lower half portion 112 of the carrier 110 in this way, the region surrounded by these grooves 114 can be defined as a convex portion 115. That is, this convex portion 115 is a portion that protrudes downward relative to the carrier 110 with respect to the portion where the groove 114 is formed. The convex portion 115 formed in the lower half portion 112 of the carrier 110 becomes a portion where the opening 122 of the support material 120 described later is fitted. In other words, the frame portion 121 of the support material 120 described later is inserted into the grooves 114 in the lower half portion 112 of the carrier 110.

[0038] Also, as shown in FIG. 4 and the like, the through holes 113 of the carrier 110 are basically formed at positions corresponding to the convex portions 115 in the lower half portion 112. That is, one through hole 113 is formed for each convex portion 115, and is formed substantially at the center of the convex portion 115. In this way, it is good to form one through hole 113 for each convex portion 115.

[0039] Also, as shown in FIGS. 2 to 4, the carrier 110 has a plurality of defective portions 116 formed at multiple locations. This defective portion 116 is a portion that penetrates from the upper surface to the lower surface of the carrier 110, similar to the through hole 113. However, the defective portion 116 is not limited to the form of a hole formed in the carrier 110, but also includes the form of a notch formed at the periphery or corner of the carrier 110. Generally, the area of this defective portion 116 is larger than that of the aforementioned through hole 113. This defective portion 116 is formed to avoid the direct contact between the leg portion 123 of the support member 120 described later and the carrier 110. Therefore, the defective portion 116 is formed at a position corresponding to the leg portion 123 of the support member 120, and basically, the number of defective portions 116 of the carrier 110 and the leg portions 123 of the support member 120 is preferably the same.

[0040] The structure of the support member 120 is shown in the perspective view of FIG. 2 and the plan view of FIG. 5. As shown in these figures, the support member 120 has a lattice-shaped frame portion 121, and the carrier 110 can be placed on this frame portion 121. That is, the frame portion 121 is regularly provided with square openings 122 in the planar direction (XY direction), and these openings 122 are arranged at equal intervals in the left-right direction (X-axis direction) and the depth direction (Y-axis direction), respectively. The convex portion 115 of the carrier 110, which is also formed in a square shape, can be fitted into the opening 122 of this frame portion 121. In other words, the lattice-shaped frame portion 121 can be inserted into the groove 114 of the carrier 110, which is also formed in a lattice shape. In this way, when placing the carrier 110 on the support member 120, the convex portion 115 of the carrier 110 is fitted into the opening 122 of the support member 120. Thereby, the carrier 110 is stably supported by the support member 120.

[0041] Further, as shown in FIG. 2, the support member 120 is provided with a plurality of legs 123 extending downward therefrom. The support members 120 can be stacked in multiple layers vertically, but in this case, it is necessary to ensure a space for arranging the carrier 110 between the upper and lower support members 120. Therefore, the legs 123 are provided on the support member 120 to ensure such a space for arranging the carrier 110. The plurality of legs 123 are preferably provided at equal intervals in the left-right direction (X-axis direction) and the depth direction (Y-axis direction), respectively. Also, if the interval between the legs 123 is too wide, the frame portion 121 may be partially deflected by the weight of the carrier 110, and there is a risk that the contaminated water may concentrate and flow into the deflected portion. Therefore, in order to suppress the deflection of the frame portion 121, the interval between the legs 123 is preferably about 50 to 200 mm, and particularly preferably 60 to 180 mm or 80 to 160 mm.

[0042] Further, the legs 123 are preferably provided not only at the periphery of the frame portion 121 but also in the middle of the frame portion 121. Thereby, when the carrier 110 is supported by the support member 120, it is possible to suppress the center of the frame portion 121 from being greatly deflected downward. In the illustrated example, a total of 16 legs 123 are provided on the support member 120, 12 of which are provided along the periphery of the support member 120, and the remaining 4 are provided in the middle of the support member 120. If a square region with the four legs 123 as the four corners is defined as one section, it can be considered that a total of 9 sections of 3×3 are formed in the illustrated example.

[0043] Further, on the support member 120 directly above the leg portion 123, a leg receiving portion 124 is provided. The leg receiving portion 124 is formed so as to block a part of the opening 122 in the lattice-shaped frame portion 121, and the opening 122 does not exist at the position where the leg receiving portion 124 is provided. When stacking a plurality of support members 120, the leg receiving portion 124 of the support member 120 has the leg portion 123 of another support member 120 located above it placed thereon. In this way, by receiving the leg portion 123 of the upper support member 120 by the leg receiving portion 124 of the lower support member 120, a plurality of support members 120 can be stacked in the vertical direction. Further, a leg receiving groove 125 into which the lower end of the leg portion 123 fits may be formed in the leg receiving portion 124. By providing such a leg receiving groove 125, when the leg portion 123 is placed on the leg receiving portion 124, it is possible to prevent the leg portion 123 from shifting on the leg receiving portion 124 or falling off the leg receiving portion 124.

[0044] The material forming the support member 120 is preferably one that can be used over a long period in water treatment and has a certain rigidity so as to suppress deflection when supporting the carrier 110. For example, the support member 120 may be made of a resin such as polypropylene or may be made of a metal such as stainless steel. It can be said that the smaller the amount of deflection of the support member 120 when supporting the carrier 110, the better. For example, when the carrier 110 completely filled with water is placed on the support member 120, the amount of deflection of the support member 120 is preferably 3 mm or less, and particularly preferably 1 mm or less, at the position where the amount of deflection is the largest between the leg portions 123.

[0045] FIG. 6 is a side view of the sewage treatment unit 100 in a state where the carrier 110 and the support material 120 are combined. As described above, the carrier 110 and the support material 120 are combined by fitting the convex portion 115 on the lower surface side of the carrier 110 into the opening 122 of the support material 120. As shown in FIG. 6, in a state where the convex portion 115 is completely fitted into the opening 122, the convex portion 115 of the carrier 110 preferably protrudes from the lower surface of the support material 120. In FIG. 6, the protruding length of the convex portion 115 of the carrier 110 extending from the lower surface of the support material 120 is indicated by the symbol P. The protruding length P is the length from the lower surface of the support material 120 to the apex of the convex portion 115 of the carrier 110. That is, the protruding length P is obtained by the difference between the height of the convex portion 115 of the carrier 110 and the thickness of the frame portion 121 of the support material 120. The protruding length P may be 1 mm or more, for example, preferably 1 to 20 mm, and particularly preferably 5 to 15 mm.

[0046] FIG. 7 shows a side view of a state in which a plurality of sewage treatment units 100 are stacked in multiple stages. In the example shown in FIG. 7, three sewage treatment units 100 are stacked. As shown in FIG. 7, there is a gap C between the carrier 110 supported by the lower support member 120 and the carrier 110 supported by the upper support member 120 above it. That is, even when the sewage treatment units 100 are stacked vertically, the thickness of the carrier 110, the length of the leg portion 123, and the protruding length P (see FIG. 6) of the convex portion 115 of the carrier 110 are adjusted so that the upper and lower carriers 110 do not come into direct contact with each other. Specifically, the height of the gap C between the upper and lower carriers 110 is preferably at least 3 mm or more, and particularly preferably 5 to 30 mm or 10 to 25 mm. If the gap C between the upper and lower carriers 110 is less than 3 mm in the initial state, solid substances such as organisms will accumulate between the carriers 110 as sewage treatment progresses and the gap C will be filled. Therefore, it is preferable to ensure that the gap C is 3 mm or more in the initial state. On the other hand, if the gap C exceeds 30 mm, it means that the leg portion 123 of the support member 120 is too long relative to the thickness of the carrier 110. Since designing the leg portion 123 to be long will unnecessarily increase the manufacturing cost of the sewage treatment unit 100, it is appropriate to set the gap C to 30 mm or less. For example, the length of the leg portion 123 of the support member 120 relative to the thickness of the carrier 110 is preferably +5 to 25 mm or +10 to 20 mm.

[0047] FIG. 8 shows a modified example of the support member 120. As shown in FIG. 8, a protrusion 126 is formed on the lower surface of the frame portion 121 of the support member 120 according to the modified example. This protrusion 126 is at least lower in the vertical direction than the leg portion 123. If water slides horizontally on the lower surface side of the support member 120, it may prevent the uniform dispersion of water in the carrier 110. However, by providing such a protrusion 126 on the lower surface of the frame portion 121, it is possible to prevent the water from flowing horizontally beyond this protrusion 126. That is, this protrusion 126 becomes the lowest part, and water drips downward from this protrusion 126.

[0048] The vertical height of the protrusion 126 is sufficient if it is 1 mm or more, and for example, it may be 1 to 5 mm or 1 to 3 mm. Also, the lateral length (diameter) of the protrusion 126 may be, for example, 1 to 10 mm. The shape of the protrusion 126 may be hemispherical (semicircular in cross-section) as illustrated in FIG. 8, or may be other shapes such as a prismatic shape, a cylindrical shape, a pyramidal shape, or a conical shape.

[0049] Also, it is preferable to provide one or more protrusions 126 between the legs 123. For example, as in the example shown in FIG. 2, when a total of 16 legs 123 are provided on the support member 120, if a square region with 4 legs 123 at the four corners is taken as one section, it can be considered that a total of 9 sections of 3×3 are formed. When assuming that one section is formed by 4 legs 123 in this way, it is preferable to provide at least one or more protrusions 126 in one section. Note that it is also possible to provide, for example, 2 to 5 protrusions 126 in one section. In addition, it is also possible to provide protrusions 126 at all the intersections of the lattice that constitutes the frame portion 121, for example.

[0050] As described above, in this specification, in order to express the content of the present invention, the embodiments of the present invention have been described with reference to the drawings. However, the present invention is not limited to the above embodiments, and includes obvious modification forms and improvement forms that those skilled in the art can make based on the matters described in this specification.

[0051] For example, in the illustrated example, the frame portion 121 of the support member 120 has a square lattice shape in which the opening 122 is square, but it is not limited to this, and for example, it is also possible to have a honeycomb shape in which the opening 122 is regular hexagonal. In this case, the shape of the groove 114 formed on the lower surface of the carrier 110 also becomes a honeycomb shape according to the shape of the frame portion 121 of the support member 120. Also, the shape of the convex portion 115 surrounded by the groove 114 on the lower surface of the carrier 110 is regular hexagonal.

[0052] In addition, the sewage treatment unit 100 may be fixed by fixing means to another sewage treatment unit 100 adjacent in the planar direction (XY direction). As the fixing means in the planar direction, for example, it is conceivable to fix the leg portions 123 of the support members 120 of the sewage treatment units 100 adjacent to the left and right with an adhesive, or to fix them using a tape or a string. Also, as the fixing means in the planar direction, the leg portions 123 of the support members 120 of the sewage treatment units 100 adjacent to the left and right may be fixed with a fixture such as a removable metal fitting.

[0053] In addition, the sewage treatment unit 100 may be fixed by fixing means to another sewage treatment unit 100 stacked in the vertical direction (Z direction). As the fixing means in the vertical direction, for example, holes are provided in the leg portions 123 of the support members 120 of the sewage treatment units 100 adjacent vertically, and a connection piece to which a locking member fixed to the support member 120 directly below is attached is inserted into the holes of each leg portion 123, so that the upper and lower support members 120 are fixed so as not to move.

Explanation of Reference Numerals

[0054] 1... Purification device 10... Treatment tank 11... Bottom plate 11a... Liquid passage hole 20... Sprinkler device 21... Sewage supply pipe 22... Receiving member 23... Drain pipe 24... Branch pipe 25... Nozzle 30... Dispersion layer 31... Foam 40... Water collection part 41... Drain pipe 100... Sewage treatment unit 110... Carrier 111... Upper half part 112... Lower half part 113... Through hole 114... Groove 115... Protrusion 116... Defective part 120... Support member 121... Frame part 122... Opening 123... Leg part 124... Leg receiving part 125... Leg receiving groove 126... Protrusion P... Projection length C... Clearance

Claims

1. A wastewater treatment unit for performing a microbial reaction treatment on wastewater, A carrier capable of retaining microorganisms; a support member having a plurality of openings formed therein for supporting the carrier from a lower surface side; The support materials are stacked such that the carrier can be disposed between the upper and lower support materials, The carrier has a plurality of through holes penetrating in the thickness direction thereof. Sewage treatment unit.

2. When the carrier is placed on the support material, the through hole of the carrier communicates with the opening of the support material.

2. A wastewater treatment unit according to claim 1.

3. The carrier has a plurality of protrusions on a lower surface side, the protrusions being surrounded by grooves, The protrusion of the carrier fits into the opening of the support material.

2. A wastewater treatment unit according to claim 1.

4. When the protrusion of the carrier is fitted into the opening of the support material, the apex of the protrusion protrudes from the lower surface of the support material. A wastewater treatment unit according to claim 3.

5. The through hole is formed in at least one of the plurality of protrusions. A wastewater treatment unit according to claim 3.

6. The support material is A plurality of legs extending downward therefrom; A leg receiving portion is provided for supporting the legs of other supporting materials stacked above the leg receiving portion, The carrier has a cutout formed therein to prevent the carrier from coming into contact with the leg of the other support material.

2. A wastewater treatment unit according to claim 1.

7. The support material is A plurality of legs extending downward therefrom; A leg receiving portion is provided for supporting the legs of other supporting materials stacked above the leg receiving portion, The length of the leg of the support material is greater than the thickness of the carrier; When the carrier is placed on the support material, a gap is generated between the carrier and other support materials stacked above it.

2. A wastewater treatment unit according to claim 1.

8. The support material is A plurality of legs extending downward therefrom; A leg support portion for supporting the legs of other support materials stacked above it; On its underside, it has a plurality of protrusions that are lower in height than the legs.

2. A wastewater treatment unit according to claim 1.

9. The support material is formed in a lattice or honeycomb shape.

2. A wastewater treatment unit according to claim 1.

10. A sprinkler-type purification device for performing microbial reaction treatment on wastewater, A treatment tank in which a plurality of wastewater treatment units according to claim 1 are arranged; A sprinkler device is provided to sprinkle wastewater from above the treatment tank. Purification equipment.

11. A water-spray purification method for performing a microbial reaction treatment on wastewater, comprising the steps of: A step of supplying wastewater to a treatment tank in which a plurality of wastewater treatment units according to claim 1 are arranged; The method includes a step of subjecting the wastewater to a microbial reaction treatment in the treatment tank by the wastewater treatment unit containing microorganisms. Purification methods.

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