Fermentation apparatus

Abstract

To provide a fermentation apparatus with improved fermentation efficiency of treated water. [Solution] A fermentation apparatus 1 configured to ferment organic matter contained in water to be treated W using microorganisms, comprising: a fermentation tank 2; a plurality of fermentation units 3 arranged in the fermentation tank 2; a plurality of microbial carriers 31 held inside each fermentation unit 3 and configured to carry microorganisms; and a water to be treated spraying unit 5 for spraying water to be treated W onto the fermentation units 3, wherein at least one of the plurality of fermentation units 3 is positioned above another fermentation unit 3, and each fermentation unit 3 is provided with a support member 6 for forming a space inside and is configured to allow water to be treated W to pass through.

Description

[Technical Field]

[0001] This invention relates to a fermentation apparatus. [Background technology]

[0002] Traditionally, fermentation by microorganisms has been used to remove organic matter from treated water containing organic matter and to recover resources. As an efficient method for water treatment using microorganisms, the Down-flow Hanging Sponge (DHS) method is known, in which treated water is sprayed onto a microbial carrier on which sludge containing microorganisms is supported, and the treated water is fermented by the microorganisms in the sludge while the treated water permeates through by gravity.

[0003] For example, Patent Document 1 describes a fermentation apparatus comprising a reactor to which water to be treated is supplied, and a plurality of microbial carriers filled inside the reactor. Microorganisms that ferment the water to be treated are attached to the microbial carriers. The microbial carriers are mainly composed of sponge. A ring-shaped frame is fitted into each microbial carrier to maintain its shape. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2013-17946 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, with the above technology, since a frame is fitted into the microbial carrier, the amount of microorganisms supported on the carrier is reduced by the volume of the frame. This raises concerns that the fermentation efficiency of the treated water by the microorganisms will decrease. To solve the above problem, one possible solution is to remove the frame from each microbial carrier.

[0006] However, removing the frame makes it difficult to maintain the shape of the microbial carriers. As a result, if the microbial carriers are stacked high in the reactor, there is a risk that the microbial carriers located at the bottom of the reactor may be crushed. This raises concerns that the pore structure of the microbial carriers may be crushed, or that the volume of the microbial carriers may decrease due to compression. Consequently, there are concerns that the fermentation efficiency of the treated water by microorganisms may decrease.

[0007] This invention has been made in view of the above problems, and aims to provide a fermentation apparatus that improves the fermentation efficiency of the treated water. [Means for solving the problem]

[0008] One aspect of the present invention is, A fermentation apparatus configured to ferment organic matter contained in the water to be treated using microorganisms, Fermentation tank and Multiple fermentation units arranged within the fermentation tank, A plurality of microbial carriers are provided, which are held inside each of the fermentation units and are configured to support the microorganisms, The fermentation unit has a water treatment spraying unit that sprays the water to be treated onto it, At least one of the multiple fermentation units is positioned above the other fermentation units, The fermentation unit is part of a fermentation apparatus that includes a support member for forming a space inside it and is configured to allow the treated water to pass through. [Effects of the Invention]

[0009] According to one aspect of the present invention, a space for accommodating the microorganism carrier is formed and maintained inside the fermentation unit by a support member. Thereby, the shape of the microorganism carrier disposed inside the fermentation unit can be maintained. As a result, even when the fermentation unit holding the microorganism carrier is disposed at the lower part of the fermentation tank, the shape of the microorganism carrier in the fermentation unit can be maintained. Therefore, it is possible to suppress the crushing of the microorganism carrier, and thus the fermentation efficiency of the treated water can be improved.

[0010] As described above, according to the above aspect, it is possible to provide a fermentation apparatus with improved fermentation efficiency of treated water.

Brief Description of Drawings

[0011] [Figure 1] FIG. 1 is a cross-sectional view showing a main part of the fermentation apparatus in Embodiment 1. [Figure 2] FIG. 2 is a cross-sectional view showing the fermentation unit in Embodiment 1. [Figure 3] FIG. 3 is a plan view showing the net-like first lid portion and second lid portion in Embodiment 1. [Figure 4] FIG. 4 is a plan view showing the plate-like first lid portion and second lid portion in Embodiment 1. [Figure 5] FIG. 5 is a schematic diagram for explaining the minimum transfer dimension dmin of the microorganism carrier in Embodiment 1. [Figure 6] FIG. 6 is a cross-sectional view showing the conductive intermediate member in Embodiment 1. [Figure 7] FIG. 7 is a cross-sectional view showing a main part of the fermentation apparatus in Embodiment 2. [Figure 8] FIG. 8 is a cross-sectional view showing the fermentation unit in Embodiment 3. [Figure 9] FIG. 9 is a partially enlarged cross-sectional view showing a main part of the fermentation tank in Embodiment 4. [Figure 10] FIG. 10 is a partial cross-sectional view showing the fermentation unit in Embodiment 5 and a partially enlarged view showing the conductive intermediate member. [Figure 11]FIG. 11 is a cross-sectional view showing a main part of the fermentation apparatus in Embodiment 6. [Figure 12] FIG. 12 is a cross-sectional view showing the fermentation unit of Embodiment 7.

MODE FOR CARRYING OUT THE INVENTION

[0012] (Embodiment 1) Embodiment 1 of the fermentation apparatus will be described with reference to FIGS. 1 to 6. The fermentation apparatus 1 of the present Embodiment 1 is configured to be able to ferment the organic substances contained in the water to be treated W by microorganisms. The fermentation apparatus 1 includes a fermentation tank 2, a plurality of fermentation units 3 disposed in the fermentation tank 2, a plurality of microorganism carriers 31 held inside each fermentation unit 3 and configured to be able to carry microorganisms, and a water-to-be-treated water spraying unit 5 that sprays the water to be treated W onto the fermentation unit 3. Another fermentation unit 3 is disposed above at least one of the plurality of fermentation units 3. The fermentation unit 3 includes a support member 6 for forming a space inside thereof and is configured to allow the water to be treated W to permeate therethrough.

[0013] The water to be treated W used in the fermentation apparatus 1 is not particularly limited, and the water to be treated W containing desired organic substances can be used. As the water to be treated W, for example, sewage containing organic wastes such as sewage sludge and food residues can be used. Also, as the water to be treated W, for example, industrial wastewater containing organic substances such as waste water-soluble coolant recovered from a processing apparatus performing machining can be used. In the following description, for a plurality of identical members, only some members may be labeled with reference numerals, and the reference numerals of other members may be omitted.

[0014] The shape and size of the fermentation tank 2 can take various forms. For example, the shape of the fermentation tank 2 in the fermentation apparatus 1 of the present Embodiment 1 is cylindrical. The height and diameter of the fermentation tank 2 in the present embodiment are each 2 m.

[0015] As shown in Figure 1, a partition plate 21 is provided inside the fermentation tank 2, which is configured to allow the water to be treated W to flow through. The space inside the fermentation tank 2 is divided by the partition plate 21 into two spaces: an upper space 22 in which multiple fermentation units 3 are held, and a lower space 23 in which the water to be treated W is held.

[0016] The upper space 22 of the fermentation tank 2 contains multiple (three in this embodiment 1) fermentation units 3, a conductive intermediary member 4, and a water treatment spraying unit 5. The number of fermentation units 3 may be two or four or more.

[0017] The upper space 22 of the fermentation tank 2 may be provided with a gas outlet pipe 24 that guides the gas generated by the fermentation of the water to be treated W to the outside of the fermentation tank 2. For example, in this embodiment 1, the gas outlet pipe 24 is provided at the upper end of the fermentation tank 2.

[0018] In the lower space 23 of the fermentation tank 2, there is a treated water outlet pipe 25 that guides the treated water W, which has been fermented by microorganisms, to the outside of the fermentation tank 2.

[0019] Each fermentation unit 3 (3a, 3b, 3c) holds multiple microbial carriers 31 inside. The microbial carriers 31 are configured to carry microorganisms. According to this embodiment 1, since multiple microbial carriers 31 are held by the fermentation unit 3, multiple microbial carriers 31 can be transported together for each fermentation unit 3. In addition, multiple microbial carriers 31 can be replaced for each fermentation unit 3. As a result, the maintainability of the fermentation apparatus 1 can be improved.

[0020] The type of microorganism supported on the microbial carrier 31 is not particularly limited and can be appropriately selected according to the type of organic matter in the treated water W and the desired mode of fermentation. From the viewpoint of further improving the fermentation efficiency in the fermentation apparatus 1, it is preferable that the microorganisms supported on the microbial carrier 31 include organic matter-conforming bacteria that have the property of fermenting organic matter in the treated water W, and electron-releasing bacteria that have the property of receiving electrons taken in from the outside and moving to the organic matter-conforming bacteria. In this case, the fermentation of organic matter by the organic matter-conforming bacteria can be promoted by the exchange of electrons between the electron-releasing bacteria and the organic matter-conforming bacteria.

[0021] For example, the microbial carrier 31 in the fermentation apparatus 1 of this embodiment carries methane-producing bacteria as organic matter-converting bacteria, and is configured to ferment organic matter in the water to be treated W and generate biogas containing methane. Examples of methane-producing bacteria include Methanobacterium and Methanosarcina.

[0022] Electron-releasing bacteria have the property of transferring electrons taken in from the outside to organic matter-conforming bacteria. Examples of microorganisms with this property include Morganella morganii and Proteus mirabilis.

[0023] Multiple fermentation units 3 are arranged on the partition plate 21 of the fermentation tank 2. In addition, at least one of the multiple fermentation units 3 is positioned above another fermentation unit 3. Some of the multiple fermentation units 3 may be arranged horizontally in a line with each other. This allows for efficient arrangement of the fermentation units 3 inside the fermentation tank 2, thereby improving the fermentation efficiency of the treated water W inside the fermentation tank 2.

[0024] More specifically, the fermentation apparatus 1 of this embodiment 1 has three fermentation units 3 (3a, 3b, 3c), and the fermentation units 3 and conductive intermediary members 4 are stacked alternately in the vertical direction. For convenience, the fermentation unit 3 located at the top will be referred to as the first fermentation unit 3a, the fermentation unit 3 located in the middle will be referred to as the second fermentation unit 3b, and the fermentation unit 3 located at the bottom will be referred to as the third fermentation unit 3c.

[0025] As shown in Figure 1, in the fermentation apparatus 1 of this embodiment 1, among the multiple fermentation units 3, all fermentation units 3b and 3c except for the first fermentation unit 3a located at the top are positioned above the other fermentation units 3a and 3b. In other words, the other fermentation units 3b are positioned above the fermentation unit 3c placed on the partition plate 21, and the other fermentation units 3a are positioned above those fermentation units 3. According to this embodiment 1, the fermentation units 3 can be efficiently housed in the fermentation tank 2. This makes it possible to improve the fermentation efficiency of the water to be treated W in the fermentation tank 2.

[0026] The shape of the fermentation unit 3 is not particularly limited, and any shape can be adopted. In this embodiment 1, the fermentation unit 3 is formed in a cylindrical shape. The outer diameter of the fermentation unit 3 is the same as, or slightly smaller than, the inner diameter of the fermentation tank 2. However, the shape of the fermentation unit 3 may also be a prism shape such as a triangular prism or a square prism.

[0027] Furthermore, the shape of the fermentation unit 3 may be a columnar shape with a fan-shaped top and bottom, such that it is formed when a cylinder is cut along a plane in the axial direction. In this case, multiple fermentation units 3 with fan-shaped tops and bottoms may be arranged side by side in the circumferential direction (horizontal direction) to form a cylindrical shape overall.

[0028] The treated water spraying unit 5 is configured to spray the treated water W onto the fermentation unit 3. As shown in Figure 1, the treated water spraying unit 5 of this embodiment 1 is positioned above the first fermentation unit 3a and is configured to spray the treated water W onto the fermentation unit 3 from above the first fermentation unit 3a. The specific configuration of the treated water spraying unit 5 is not limited to the configuration of this embodiment 1 and can take various forms. Although not shown in the figure, for example, the treated water spraying unit 5 may be positioned along the side surface of the upper space 22 of the fermentation tank 2 and configured to spray the treated water W onto the fermentation unit 3 from the side of the fermentation unit 3.

[0029] From the viewpoint of easily distributing the water to be treated W throughout the fermentation unit 3 in the fermentation tank 2, it is preferable that the water to be treated spraying unit 5 be positioned above the first fermentation unit 3a, which is located at the top of the fermentation tank 2. As the water to be treated spraying unit 5, for example, a spraying nozzle configured to spray the water to be treated W into the fermentation tank 2, or a spraying pipe equipped with small holes for releasing the water to be treated W can be used.

[0030] The supply route of the water to be treated W from outside the fermentation apparatus 1 to the water to be treated spraying section 5 can take various forms. For example, in this embodiment 1, the water to be treated spraying section 5 is configured to directly spray the water to be treated W supplied from outside the fermentation apparatus 1. Although not shown in the figure, the water to be treated spraying section 5 may also be configured to spray the water to be treated W stored in the lower space 23 onto the fermentation unit 3.

[0031] The fermentation unit 3 is equipped with a support member 6 to form a space inside it. The support member 6 is configured to allow the water to be treated W to pass through. According to this embodiment 1, the support member 6 forms a space inside the fermentation unit 3 for housing the microbial carrier 31. Furthermore, the support member 6 can maintain the space inside the fermentation unit 3 even when other members are stacked on top of the fermentation unit 3. Therefore, by providing the support member 6 in the fermentation unit 3, the shape of the microbial carrier 31 placed inside the fermentation unit 3 can be maintained. As a result, even if the fermentation unit 3 holding the microbial carrier 31 is placed at the bottom of the fermentation tank 2, the shape of the microbial carrier 31 inside the fermentation unit 3 can be maintained. In this embodiment 1, the shape of the microbial carrier 31 held in the third fermentation unit 3c located at the bottom of the fermentation tank 2 can be maintained. Therefore, crushing of the microbial carrier 31 can be suppressed, and the fermentation efficiency of the water to be treated W can be improved.

[0032] The material constituting the support member 6 is not particularly limited and may be composed of a conductor, a semiconductor, an insulator, or two or more materials selected from conductors, semiconductors, and insulators. The support member 6 according to this embodiment 1 is made of a resin which is an insulator. However, ceramic may be used as the insulator, for example.

[0033] As shown in Figure 2, the support member 6 comprises a cylindrical support frame 63 having a first opening 61 and a second opening 62, a first lid 64 covering the first opening 61, and a second lid 65 covering the second opening 62. In this embodiment 1, within the fermentation tank 2, the support member 6 is positioned with the first opening 61 facing upward and the second opening 62 facing downward. However, the arrangement of the first opening 61 and the second opening 62 is not limited to the configuration of this embodiment 1.

[0034] In this embodiment 1, the water to be treated W permeates through the first lid 64 and enters the interior of the fermentation unit 3, coming into contact with the microbial carrier 31 held inside the fermentation unit 3. As a result, the water to be treated W ferments. Subsequently, the water to be treated W, from which organic matter has been fermented, flows out of the fermentation unit 3 by permeating through the second lid 65. Thus, the organic matter contained in the water to be treated W is fermented inside the fermentation unit 3.

[0035] The support frame 63, the first lid 64, and the second lid 65 may be formed as a single unit. This allows the shape of the fermentation unit 3 to be more firmly maintained.

[0036] The support frame 63, the first lid 64, and the second lid 65 may be constructed as separate components. For example, the first lid 64 may be attached to the opening edge of the first opening 61 of the support frame 63, and the second lid 65 may be attached to the opening edge of the second opening 62 of the support frame 63. Alternatively, the support frame 63 and the second lid 65 may be formed integrally, with the first lid 64 attached to the opening edge of the first opening 61 of the support frame 63. Similarly, the support frame 63 and the first lid 64 may be formed integrally, with the second lid 65 attached to the opening edge of the second opening 62 of the support frame 63. In this way, the microbial carrier 31 can be easily held inside the support member 6.

[0037] The configuration for attaching the first lid 64 or the second lid 65 to the support frame 63 is not particularly limited. For example, the first lid 64 or the second lid 65 may be attached to the support frame 63 by elastic engagement between a locking portion (not shown) provided on the support frame 63 and a locking receiving portion (not shown) provided on the first lid 64 or the second lid 65. Alternatively, the support frame 63 and the first lid 64 or the second lid 65 may be rotatably attached by a hinge (not shown).

[0038] The support frame 63 according to this embodiment 1 is formed in a cylindrical shape. However, the support frame 63 can take any shape, such as a rectangular tube. The support frame 63 of this embodiment 1 may be formed in a solid wall shape, as shown in Figure 2. It is preferable that the support frame 63 has sufficient rigidity to not deform when placed inside the fermentation tank 2. In this case, the support frame 63 can reliably form a space inside the fermentation unit 3 for housing the microbial carrier 31.

[0039] However, the support frame 63 may be formed in the shape of a wall with multiple through holes (not shown), or it may be formed in the shape of a mesh (not shown). In this case, the water to be treated W can enter the interior of the fermentation unit 3 through the through holes or mesh, and can also move from the fermentation unit 3 to the outside. This ensures that the water to be treated W and the microbial carrier 31 held inside the fermentation unit 3 come into contact.

[0040] The first lid 64 and the second lid 65 are configured to allow the water to be treated W to pass through. The shape of the first lid 64 and the second lid 65 in this embodiment 1 is a mesh shape having meshes 64a and 65a as shown in Figure 3. In this case, the water to be treated W can enter the inside of the fermentation unit 3 through the meshes 64a and 65a and move from the fermentation unit 3 to the outside. This ensures that the water to be treated W and the microbial carrier 31 held inside the fermentation unit 3 come into contact. The first lid 64 and the second lid 65 may be configured as a mesh made of bundled wires of multiple fibers, or as a mesh made of resin.

[0041] However, the shapes of the first lid 64 and the second lid 65 may be plate-like with through holes 64b and 65b as shown in Figure 4. The shapes of the through holes 64b and 65b are not particularly limited and may be circular, elliptical, track-shaped, triangular, quadrilateral, or other polygonal shapes.

[0042] According to this embodiment 1, the water to be treated W can easily enter the fermentation unit 3 through the mesh 64a, 65a and through holes 64b, 65b. As a result, the water to be treated W can be uniformly distributed by the microbial carrier 31, and the organic matter contained in the water to be treated W can be efficiently fermented.

[0043] Furthermore, the treated water W, from which organic matter has been fermented by microorganisms, can easily flow out of the fermentation unit 3 through the mesh 64a, 65a and through holes 64b, 65b. This prevents the treated water W from remaining inside the fermentation unit 3, allowing the organic matter contained in the treated water W to be fermented efficiently.

[0044] Multiple microbial carriers 31 are held inside the fermentation unit 3. The microbial carriers 31 are not particularly limited, and any material can be selected, such as a polymer porous body 31a or a water-swellable resin. In this embodiment 1, the microbial carrier 31 is composed solely of a polymer porous body 31a (see Figure 5). In other words, the microbial carrier 31 in this embodiment 1 is not fitted into a frame. As a result, in the fermentation apparatus 1 of this embodiment 1, the amount of microorganisms supported on each microbial carrier 31 can be increased compared to the case where each microbial carrier 31 is fitted into a frame. Therefore, the microbial carrier 31 made solely of a polymer porous body 31a has an improved overall microbial support rate compared to the case where each microbial carrier 31 is fitted into a frame, thus improving the fermentation efficiency of the treated water W.

[0045] The conductivity of the microbial carrier 31 is not particularly limited; it may be non-conductive or conductive. However, it is preferable that the microbial carrier 31 is composed of a conductor and / or semiconductor. That is, for example, if the microbial carrier 31 is a porous body, it is preferable that the porous body is a conductor or a semiconductor. By composing the microbial carrier 31 from a conductor and / or semiconductor in this way, electrons emitted from electron-emitting bacteria can be supplied not only to organic matter-conforming bacteria located near the electron-emitting bacteria, but also to organic matter-conforming bacteria located at a distance from the electron-emitting bacteria. This improves fermentation efficiency. Note that the aforementioned "conductor" refers to 10 6 A material having an electrical conductivity of S / m or higher is called a "semiconductor," and the term "semiconductor" is defined as 10 -6 S / m or more 10 6 This refers to a substance having an electrical conductivity of less than S / m.

[0046] Preferably, the microbial carrier 31 is pressed by the support member 6 of the fermentation unit 3. For example, in this embodiment 1, the microbial carrier 31 is pressed vertically and / or horizontally by the support member 6 and is filled into the fermentation unit 3 in a state that is slightly more compressed than its natural state. However, the microbial carrier 31 may also be configured to be filled into the fermentation unit 3 in its natural state.

[0047] By pressing the microbial carriers 31 with the support members 6, adjacent microbial carriers 31 in the fermentation tank 2 are more likely to come into contact with each other. When adjacent microbial carriers 31 come into contact, they are more likely to be electrically connected to each other. As a result, electron transfer between electron-releasing bacteria and organic matter-conforming bacteria supported on different microbial carriers 31 becomes easier, thus more reliably achieving an improvement in fermentation efficiency.

[0048] The size of the microbial carrier 31 is not particularly limited, as long as it is sufficiently smaller than the fermentation unit 3. For example, the size of the microbial carrier 31 should be such that it can be contained within a rectangular prism with sides of 100 mm.

[0049] When the microbial carrier 31 is composed solely of a polymer porous body 31a, it is preferable that the polymer porous body 31a has a hardness H that satisfies the following formula (1). H≧gh1π×10 -2 ...(1)

[0050] However, in formula (1) above, H is the hardness (in N) of the polymer porous material 31a produced by method A as specified in JIS K6400-2:2012, h1 is the height dimension (in mm) of the internal shape of the fermentation unit 3, and g is the standard gravitational acceleration constant (in m / s²). 2 ) where π is the ratio of a circle's circumference to its diameter. The height dimension h1 of the internal shape of the fermentation unit 3 refers to the distance between the inner surface of the second lid 65 and the inner surface of the first lid 64 of the support member 6 that constitutes the fermentation unit 3 (see Figure 2).

[0051] A polymer porous material 31a having a hardness H within the specified range is less likely to collapse even when filled into a fermentation unit 3 with an internal height dimension h1. Therefore, by using such a polymer porous material 31a as a microbial carrier 31, the microbial carrier 31 can be packed more densely into the fermentation unit 3 while ensuring the water permeability of the microbial carrier 31. As a result, the fermentation efficiency of the treated water W can be further increased.

[0052] However, the fermentation apparatus 1 according to this embodiment 1 is applicable to both an anaerobic fermentation tank 2 and an aerobic fermentation tank 2.

[0053] As shown in Figure 1, the conductive intermediary member 4 is positioned between adjacent fermentation units 3. The microbial carriers 31 in each fermentation unit 3 and the microbial carriers 31 in the adjacent fermentation unit 3 are electrically connected via the conductive intermediary member 4. The conductive intermediary member 4 may electrically connect adjacent microbial carriers 31 in the vertical direction, adjacent microbial carriers 31 in the horizontal direction, or adjacent microbial carriers 31 in an oblique direction inclined with respect to the vertical direction. As described above, in this embodiment 1, multiple fermentation units 3 (3a, 3b, 3c) and conductive intermediary members 4 are stacked alternately in the vertical direction, so the conductive intermediary member 4 electrically connects the microbial carriers 31 held in adjacent fermentation units 3 (3a, 3b, 3c) in the vertical direction. In this embodiment 1, two conductive intermediary members 4 are positioned in the fermentation tank 2. The number of conductive intermediary members 4 may be one or three or more.

[0054] Furthermore, the conductive intermediary member 4 can electrically connect the treated water W located within adjacent fermentation units 3 (3a, 3b, 3c). This allows for the electrical connection of the treated water W remaining within one fermentation unit 3 with the treated water W remaining within other fermentation units 3 adjacent to that unit.

[0055] As shown in Figure 6, the conductive intermediary member 4 comprises a plate portion 43 formed in a plate shape having a first surface 41 and a second surface 42, a first projection 44 protruding from the first surface 41, a second projection 45 protruding from the second surface 42, and a water permeable hole 46 penetrating the plate portion 43.

[0056] The plate portion 43, the first projection 44, and the second projection 45 may be made of the same material, or each component may be made of different materials.

[0057] The shape of the plate portion 43 can be any shape, such as a disc shape or a square shape. In this embodiment 1, the plate portion 43 is formed in a disc shape that conforms to the inner shape of the fermentation tank 2.

[0058] The material constituting the plate portion 43 can be any material, and may be composed of a conductor, a semiconductor, an insulator, or two or more materials selected from conductors, semiconductors, and insulators. In this embodiment 1, the plate portion 43 is made of a resin which is an insulator.

[0059] The plate portion 43 comprises a first surface 41 and a second surface 42 opposite to the first surface 41. In this embodiment 1, the first surface 41 of the plate portion 43 faces upward and the second surface 42 faces downward. However, the arrangement of the plate portion 43 is arbitrary; for example, the plate portion 43 may be arranged so that the first surface 41 faces downward and the second surface 42 faces upward.

[0060] The conductive intermediary member 4 is provided with permeable holes 46 that penetrate the plate portion 43. As a result, the water to be treated W that flows down the fermentation unit 3 above the conductive intermediary member 4 flows through the permeable holes 46 and is supplied to the fermentation unit 3 below the conductive intermediary member 4.

[0061] The first projection 44 and the second projection 45 are made of a conductor and / or semiconductor. The first projection 44 and the second projection 45 are continuous with each other at the base 47. The base 47 is located inside the plate portion 43. This electrically connects the first projection 44 and the second projection 45.

[0062] The shapes of the first projection 44 and the second projection 45 are not particularly limited; they may have a pointed tip, be rod-shaped, or be plate-shaped. In this embodiment 1, the first projection 44 and the second projection 45 are preferably conical in shape with a pointed tip, or polygonal pyramidal in shape such as a square pyramid.

[0063] The first projection 44 extends into the interior of the fermentation unit 3 located on the first surface 41 side of the plate portion 43. In this embodiment 1, the first projection 44 penetrates the mesh 64a, 65a of the first lid portion 64 or the second lid portion 65. As a result, the first projection 44 comes into contact with the microbial carrier 31 inside the fermentation unit 3 located on the first surface 41 side of the plate portion 43. The manner in which the first projection 44 comes into contact with the microbial carrier 31 is not particularly limited; it may be a manner in which the surface of the first projection 44 comes into contact with the surface of the microbial carrier 31, or the tip of the first projection 44 may penetrate into the interior of the microbial carrier 31.

[0064] The second projection 45 extends into the interior of the fermentation unit 3 located on the second surface 42 side of the plate portion 43. In this embodiment 1, the second projection 45 penetrates the mesh 64a, 65a of the first lid portion 64 or the second lid portion 65. As a result, the second projection 45 comes into contact with the microbial carrier 31 inside the fermentation unit 3 located on the second surface 42 side of the plate portion 43. The manner in which the second projection 45 comes into contact with the microbial carrier 31 is not particularly limited; it may be a manner in which the surface of the second projection 45 comes into contact with the surface of the microbial carrier 31, or the tip of the second projection 45 may penetrate into the interior of the microbial carrier 31.

[0065] In this embodiment 1, it is preferable that the length dimension a of one side of the mesh 64a and 65a of the first lid 64 and second lid 65 of the support member 6 of the fermentation unit 3 satisfies the following formula (2). b <a<d min ...(2) However, in equation (2), b is the maximum difference dimension (in mm) in the cross-section in the direction intersecting the protruding directions of the first projection 44 and the second projection 45 (see Figure 6), and a is the length dimension (in mm) of one side of the mesh 64a, 65a (see Figure 3). Also, d min This is the minimum cross-sectional area (in mm) in the projected figure 31b when the microbial carrier 31 is projected onto a virtual plane P such that the projected area is minimized (see Figure 5).

[0066] Refer to Figure 5 for the minimum difference dimension d minA description will be given. Fig. 5 shows a projected figure 31b when the microorganism carrier 31 is projected onto a virtual plane P so that the projected area is minimized. Among the passing dimensions in such a projected figure 31b, the minimum one is defined as the minimum passing dimension d min For example, when the microorganism carrier 31 is a cube, the length of one side of the microorganism carrier 31 is d min When the microorganism carrier 31 is a rectangular parallelepiped, the length of the short side of the microorganism carrier 31 is d min When the microorganism carrier 31 is a sphere, the diameter of the microorganism carrier 31 is d min is.

[0067] According to the first embodiment, the first protrusion 44 and the second protrusion 45 penetrate the meshes 64a and 65a, so that the microorganism carrier 31 can be easily electrically connected. Further, the microorganism carrier 31 is suppressed from falling from the meshes 64a and 65a.

[0068] The protruding height dimension h2 of the first protrusion 44 and the second protrusion 45 of the conductive intermediate member 4 according to the first embodiment preferably satisfies the following formula (3). t < h2 < d min ···(3) However, in formula (3), t is the thickness dimension (unit: mm) of the first lid portion 64 or the second lid portion 65 (see Fig. 2), and h2 is the protruding height dimension (unit: mm) of the first protrusion 44 and the second protrusion 45 (see Fig. 6). Also, d min is the minimum passing dimension (unit: mm) in the projected figure 31b when the microorganism carrier 31 is projected onto a virtual plane P so that the projected area is minimized (see Fig. 5).

[0069] According to the first embodiment, the first protrusion 44 and the second protrusion 45 can penetrate the first lid portion 64 or the second lid portion 65. Thereby, the first protrusion 44 and the second protrusion 45 can be electrically connected to the microorganism carrier 31 accommodated inside the fermentation unit 3.

[0070] In addition, it is possible to suppress the first protrusion 44 and the second protrusion 45 from piercing through the microorganism carrier 31.

[0071] Next, an example of the operation of the fermentation apparatus 1 of this embodiment 1 will be described. When operating the fermentation apparatus 1 of this embodiment 1, the water to be treated W is sprayed into the fermentation tank 2 from the water to be treated spraying section 5. The water to be treated W flows downward along the surface of the microbial carrier 31. Then, the organic matter-constituting bacteria supported on the microbial carrier 31 ferment the organic matter in the water to be treated W, thereby generating biogas.

[0072] Furthermore, the treated water W forms current paths on the surfaces of the multiple microbial carriers 31 placed inside the fermentation tank 2. In addition, since the microbial carriers 31 in this embodiment 1 are made of a conductor and / or semiconductor, the microbial carriers 31 are also included as part of the current paths.

[0073] Therefore, electron-releasing bacteria that receive electrons from the outside transfer electrons to organic matter-conforming bacteria supported on the microbial carrier 31. The organic matter-conforming bacteria that receive electrons can then efficiently ferment the organic matter in the treated water W.

[0074] Furthermore, the treated water W containing electrons moves downward along the surface of the microbial carrier 31 and diffuses throughout the fermentation tank 2, so that the treated water W comes into contact with the electron-releasing bacteria supported on the microbial carrier 31 over a wide area within the fermentation tank 2. As a result, the electron-releasing bacteria receive electrons from the treated water W. Then, the organic matter-conforming bacteria surrounding the electron-releasing bacteria receive electrons, which promotes the fermentation of organic matter in the treated water W over a wide area within the fermentation tank 2.

[0075] As described above, this fermentation apparatus 1 promotes the fermentation of organic matter through the interaction of electron-emitting bacteria and organic matter-conforming bacteria over a wide area within the fermentation tank 2, and can efficiently ferment organic matter in the water to be treated W.

[0076] (Embodiment 2) In this second embodiment, an example of a configuration in which the fermentation apparatus 102 includes a cathode 7 and an anode 8 will be described. Note that, unless otherwise specified, any reference numerals used in this second embodiment and subsequent embodiments that are the same as those used in previously described embodiments represent the same components as those in the previously described embodiments.

[0077] As shown in Figure 7, a cathode 7 and an anode 8 are positioned below the water treatment spraying section 5 in the upper space 22 of the fermentation tank 2. The cathode 7 and anode 8 are made of a conductor or semiconductor. An electric current path is formed between the cathode 7 and the anode 8 by the water treatment W flowing along the surface of the microbial carrier 31. Therefore, by applying a voltage between the cathode 7 and the anode 8 and allowing an electric current to flow, electrons can be supplied from the cathode 7 to electron-transferring bacteria in its vicinity, or the water treatment W that comes into contact with the cathode 7 can be reduced.

[0078] The arrangement, shape, and structure of the cathode 7 and anode 8 can take on various forms. For example, the number of cathodes 7 arranged in the fermenter 2 may be one or two or more. When two or more cathodes 7 are arranged in the fermenter 2, these cathodes 7 may be spaced apart from each other in the vertical direction or in the horizontal direction.

[0079] Similarly, the number of anodes 8 placed in the fermenter 2 may be one or two or more. When two or more anodes 8 are placed in the fermenter 2, these anodes 8 may be spaced apart from each other vertically or horizontally. In addition, the number of cathodes 7 and the number of anodes 8 placed in the fermenter 2 may be the same or different.

[0080] When multiple cathodes 7 are placed in the fermenter 2, it is sufficient that one of the cathodes 7 is positioned above the anode 8. Similarly, when multiple anodes 8 are placed in the fermenter 2, it is sufficient that the cathode 7 is positioned above these anodes 8. In other words, the electrode positioned furthest above the other electrodes in the fermenter 2 should be the cathode 7.

[0081] For example, the fermentation apparatus 102 of this embodiment has one cathode 7 and one anode 8, as shown in Figure 7. The cathode 7 is placed on top of the first fermentation unit 3a, which is the uppermost of the multiple fermentation units 3. The anode 8 is placed between the third fermentation unit 3c, which is the lowermost of the multiple fermentation units 3, and the partition plate 21.

[0082] The orientation of the cathode 7 and anode 8 is not particularly limited; for example, they may extend horizontally or in a direction inclined with respect to the horizontal. From the viewpoint of more uniformly distributing the treated water W reduced at the cathode 7 within the fermentation tank 2, it is preferable that the cathode 7 and anode 8 extend horizontally. The aforementioned "horizontal direction" includes not only directions strictly perpendicular to the vertical direction, but also directions inclined from the vertical direction to a degree that is generally considered horizontal. In other words, "horizontal direction" in this specification is a concept that encompasses directions that are substantially considered horizontal.

[0083] In this embodiment, the cathode 7 and anode 8 are arranged in a plane perpendicular to the vertical direction of the fermentation tank 2. Therefore, by arranging the fermentation tank 2 so that its vertical direction is parallel to the vertical direction, the cathode 7 and anode 8 can be extended horizontally.

[0084] The shapes of the cathode 7 and anode 8 can take various forms, such as rod-shaped, mesh-shaped, and plate-shaped. For example, the shape of the cathode 7 in this embodiment 2 is plate-shaped with a through hole 7a. Similarly, the shape of the anode 8 in this embodiment 2 is plate-shaped with a through hole 8a. The shapes of the cathode 7 and anode 8 may also be mesh-shaped.

[0085] As described above, the cathode 7 and anode 8 are preferably shaped like a mesh or a plate with through holes 7a and 8a. In this case, the treated water W reduced in the cathode 7 can flow downward through the gaps in the mesh or through holes 7a provided in the electrode, and be distributed more uniformly throughout the fermentation tank 2. As a result, organic matter can be fermented more efficiently. In addition, the treated water W, in which organic matter has been fermented in the fermentation tank 2, flows downward through the through holes 8a of the anode 8, allowing for efficient recovery of the treated water W.

[0086] A cathode projection 7b is formed on the lower surface of the cathode 7, projecting downwards. The cathode projection 7b extends into the interior of the fermentation unit 3 located below the cathode 7. As a result, the cathode projection 7b comes into contact with the microbial carrier 31 inside the fermentation unit 3. Consequently, the cathode 7 and the microbial carrier 31 inside the fermentation unit 3 are electrically connected.

[0087] An anode projection 8b is formed on the upper surface of the anode 8, projecting upward. The anode projection 8b extends into the interior of the fermentation unit 3 located above the anode 8. As a result, the anode projection 8b comes into contact with the microbial carrier 31 inside the fermentation unit 3. Consequently, the anode 8 and the microbial carrier 31 inside the fermentation unit 3 are electrically connected.

[0088] Next, an example of the operation of the fermentation apparatus 102 of this second embodiment will be described. When operating the fermentation apparatus 102 of this second embodiment, the water to be treated W is sprayed into the fermentation tank 2 from the water to be treated spraying unit 5, and a voltage is applied between the cathode 7 and the anode 8. The water to be treated W flows downward along the surface of the microbial carrier 31. This water to be treated W forms a current path between the cathode 7 and the anode 8. If the microbial carrier 31 is made of a conductor and / or semiconductor, the microbial carrier 31 may also constitute part of the current path between the cathode 7 and the anode 8.

[0089] When an electric current path is formed between cathode 7 and anode 8, current flows between these electrodes, supplying electrons to electron-emitting bacteria located near cathode 7. The electron-emitting bacteria, having received electrons directly from cathode 7, transfer these electrons to the organic matter-conforming bacteria supported on the microbial carrier 31. The organic matter-conforming bacteria, having received electrons, can then efficiently ferment the organic matter in the treated water W.

[0090] Furthermore, when an electric current flows between cathode 7 and anode 8, the water to be treated W that comes into contact with cathode 7 is reduced. The water to be treated W reduced at cathode 7 moves downward along the surface of the microbial carrier 31 and diffuses throughout the fermentation tank 2. When the water to be treated W reduced at cathode 7 comes into contact with electron-emitting bacteria supported on the microbial carrier 31, the electron-emitting bacteria receive electrons from cathode 7 in the water to be treated W. Then, the organic matter-conforming bacteria surrounding the electron-emitting bacteria receive electrons from cathode 7, thereby promoting the fermentation of organic matter in the water to be treated W even in locations relatively far from cathode 7.

[0091] As described above, the fermentation apparatus 102 in this form promotes the fermentation of organic matter through the interaction between electron-emitting bacteria and organic matter-conforming bacteria over a wide area within the fermentation tank 2, and can efficiently ferment the organic matter in the water to be treated W.

[0092] (Embodiment 3) This third embodiment describes examples of other embodiments of the support member.

[0093] As shown in Figure 8, the fermentation unit 303 of this embodiment 3 has an energizing section 66 made of a conductor and / or semiconductor. Furthermore, the energizing section 66 of the fermentation unit 303 and the microbial carrier 31 of an adjacent fermentation unit 303 are electrically connected to each other.

[0094] The arrangement and form of the energized portion 66 are not particularly limited and can take various forms. For example, the energized portion 66 in this embodiment 3 is a plurality of energized protrusions 66a provided on the second lid portion 65 of the support member 603 in the fermentation unit 303. The energized protrusions 66a are made of a conductor and / or semiconductor. The energized protrusions 66a are formed in a rod-like or plate-like shape that penetrates the second lid portion 65. The tip of the energized protrusion 66a may be pointed, curved, or flat. In this embodiment 3, the tip of the energized protrusion 66a is pointed.

[0095] By stacking the fermentation units 303 of this embodiment 3 in the vertical direction, the microbial carriers 31 in adjacent fermentation units 303 are electrically connected by the electrically conductive protrusions 66a. According to this embodiment 3, the conductive intermediary member 4 can be omitted, thus reducing the number of parts.

[0096] (Embodiment 4) In this fourth embodiment, another example of the energized portion 66 will be described. As shown in Figure 9, the support member 604 of this fourth embodiment has a first cover portion 64 and a second cover portion 65 as energized portions 66.

[0097] In this fourth embodiment, the first cover portion 64 and the second cover portion 65 are made of a conductor and / or semiconductor. The first cover portion 64 and the second cover portion 65 in this fourth embodiment are examples of energizing portions 66. The first cover portion 64 and the second cover portion 65 are formed in a mesh-like shape with a mesh pattern, or in a plate-like shape with through holes.

[0098] As shown in Figure 9, by stacking the fermentation units 304 vertically, the first lid 64 and second lid 65 of adjacent fermentation units 304 come into contact with each other. This electrically connects adjacent fermentation units 304. As a result, the microbial carriers 31 held within the fermentation units 304 are electrically connected. Consequently, the efficiency of fermentation of organic matter by microorganisms supported on the microbial carriers 31 can be improved.

[0099] (Embodiment 5) This fifth embodiment describes an example of another embodiment of the conductive intermediary member. As shown in Figure 10, the conductive intermediary member 405 of this fifth embodiment has a base portion 48 and four or more protrusions 49 projecting from the base portion 48. The conductive intermediary member 405 of this fifth embodiment has four protrusions 49.

[0100] At least one of the four projections 49 extends in a direction nonparallel to the plane passing through the tips of at least three other projections 49.

[0101] One of the four protrusions 49 extends into the interior of one fermentation unit 305a of the fermentation unit 305 and contacts the microbial carrier 31 of that fermentation unit 305a, while the other protrusions 49 extend into the interior of another fermentation unit 305b located next to the first fermentation unit 305a and contact the microbial carrier 31 within that fermentation unit 305b. According to this embodiment 5, the microbial carriers 31 held in adjacent fermentation units 305a and 305b can be electrically connected to each other. However, the protrusions 49 may also be configured to penetrate into the interior of the microbial carrier 31.

[0102] (Embodiment 6) In the fermentation apparatus 106 of this embodiment 6, examples of other configurations of the arrangement of the cathode 706 and anode 806 will be described. As shown in Figure 11, the cathode 706 of this embodiment 6 is located inside the fermentation unit 3. More specifically, the cathode 706 is located inside the support member 606 of the first fermentation unit 3a, which is located at the top of the fermentation tank 2. Furthermore, the cathode 706 of this embodiment 6 does not have a cathode projection 7b. However, the cathode 706 may be configured to have a cathode projection 7b.

[0103] The method for positioning the cathode 706 inside the support member 606 of the first fermentation unit 3a is not particularly limited. For example, the cathode 706 may be inserted into the support member 606 of the first fermentation unit 3a through a slit (not shown) formed in the support member 606.

[0104] Furthermore, although not shown in detail, the cathode 706 may be positioned inside the support member 606 of the first fermentation unit 3a by first placing it on the microbial carrier 31 with the first lid 64 removed, and then attaching the first lid 64 to the support frame 63.

[0105] The cathode 706 is pressed inward by the support member 606, thereby pressing it against the microbial carrier 31. This ensures that the cathode 706 and the microbial carrier 31 are reliably electrically connected.

[0106] Furthermore, the anode 806 of this embodiment 6 is also located inside the fermentation unit 3. More specifically, the anode 806 is located inside the support member 6 of the third fermentation unit 3c, which is located at the bottom of the fermentation tank 2. Also, the anode 806 of this embodiment 5 does not have an anode projection 8b. However, the anode 806 may be configured to have an anode projection 8b.

[0107] The method for arranging the anode 806 inside the support member 606 of the third fermentation unit 3c is not particularly limited. For example, the anode 806 may be inserted into the support member 606 of the third fermentation unit 3c through a slit (not shown) formed in the support member 606.

[0108] Furthermore, although not shown in detail, the anode 806 may be configured to be placed inside the support member 606 of the third fermentation unit 3c by first placing it on the microbial carrier 31 with the second lid 65 removed, and then attaching the second lid 65 to the support frame 63.

[0109] The anode 806 is pressed inward by the support member 606, thereby pressing it against the microbial carrier 31. This ensures that the anode 806 and the microbial carrier 31 are reliably electrically connected.

[0110] (Embodiment 7) This 7th embodiment describes an example of another embodiment of the fermentation unit. As shown in Figure 12, the fermentation unit 307 of this 7th embodiment includes a cylindrical support frame 63 as an example of a support member 607. The support frame 63 includes a first opening 61 and a second opening 62. The support member 607 of this 7th embodiment differs from that of the 1st embodiment in that it does not have a first lid 64 and a second lid 65. The support frame 63 is formed in a solid wall shape. This maintains the shape of the microbial carrier 31 placed in the space inside the support frame 63.

[0111] As shown in Figure 12, the fermentation unit 306 of this embodiment 7 includes a cover portion 37 that covers the support member 607. The cover portion 37 is configured to allow the water to be treated W to pass through. Although not shown in detail, the cover portion 37 is configured as a mesh having a mesh structure. The cover portion 37 may be made of a conductor and / or semiconductor, or an insulator such as resin. The cover portion 37 may be made of wire mesh or a resin mesh.

[0112] The present invention is not limited to the embodiments described above, and can be applied to various embodiments without departing from its spirit. [Explanation of symbols]

[0113] 1,102,106: Fermentation apparatus, 2: Fermentation tank, 3,303,304,305,305a,305b,306,307: Fermentation unit, 3a: First fermentation unit, 3b: Second fermentation unit, 3c: Third fermentation unit, 4,405: Conductive intermediary member, 5: Water to be treated spraying section, 6,602,604,607: Support member, 7,706: Cathode, 8,806: Anode, 31: Microbial carrier, 31a: High Molecular porous material, 31b: Projection figure, 37: Cover part, 41: First surface, 42: Second surface, 43: Plate part, 44: First protrusion, 45: Second protrusion, 46: Water permeable hole, 48: Base part, 49: Protrusion, 61: First opening, 62: Second opening, 63: Support frame, 64: First lid part, 64a: Mesh, 64b: Through hole, 65: Second lid part, 65a: Mesh, 65b: Through hole, 66: Conductive part, 66a: Conductive protrusion, W: Water to be treated

Claims

1. A fermentation apparatus configured to ferment organic matter contained in the water to be treated using microorganisms, Fermentation tank and Multiple fermentation units arranged within the fermentation tank, A plurality of microbial carriers are provided, which are held inside each of the fermentation units and are configured to support the microorganisms, The fermentation unit has a water treatment spraying unit that sprays the water to be treated onto it, At least one of the multiple fermentation units is positioned above the other fermentation units, The fermentation device comprises a fermentation unit equipped with a support member for forming a space inside it and configured to allow the treated water to pass through.

2. The aforementioned support member is A cylindrical support frame having a first opening and a second opening, A first lid portion that covers the first opening and is configured to allow the water to be treated to pass through, The fermentation apparatus according to claim 1, comprising: a second lid that covers the second opening and is configured to allow the treated water to pass through.

3. The fermentation apparatus according to claim 2, wherein the shape of the first lid and the second lid is a mesh shape with a mesh opening, or a plate shape with through holes.

4. The fermentation apparatus according to claim 1, wherein the fermentation unit comprises a cover portion configured to cover the support member and to allow the treated water to pass through.

5. The fermentation apparatus according to claim 1, wherein, of the multiple fermentation units, other fermentation units are arranged above all of the fermentation units except for the fermentation unit located at the top.

6. The fermentation apparatus according to claim 1, wherein some of the fermentation units are arranged horizontally in a line with each other.

7. The microbial carrier is composed of a polymer porous material, The fermentation apparatus according to claim 1, wherein the polymer porous body has a hardness H that satisfies the following formula (1). H≧gh １ π×10 －２ ・・・(1) (However, in formula (1), H is the hardness of the polymer porous material by method A as specified in JIS K6400-2:2012 (unit: N), and h １ is the height dimension (in mm) of the internal shape of the fermentation unit, and g is the standard gravitational acceleration (in m / s²). ２ ) and π is the ratio of a circle's circumference to its diameter (pi).

8. The fermentation apparatus according to claim 1, wherein the microbial carrier is electrically conductive.

9. The fermentation unit has an energizing section made of a conductor and / or semiconductor, The fermentation apparatus according to claim 8, wherein the energized portion of the fermentation unit and the microbial carrier of a fermentation unit adjacent to the fermentation unit are electrically connected to each other.

10. Furthermore, a conductive intermediary member is provided between adjacent fermentation units. The fermentation apparatus according to claim 8, wherein the microbial carrier in each of the fermentation units and the microbial carrier in the adjacent fermentation unit are electrically connected via the conductive intermediary member.

11. The aforementioned conductive intermediary member is A plate portion formed in the shape of a plate having a first surface and a second surface, A first projection protruding from the first surface, A second projection protruding from the second surface, It comprises a water permeable hole that penetrates the plate portion, The first projection extends into the interior of the fermentation unit located on the first surface side of the plate portion and comes into contact with the microbial carrier within the fermentation unit. The fermentation apparatus according to claim 10, wherein the second projection extends into the interior of the fermentation unit located on the second surface side of the plate portion and is in contact with the microbial carrier inside the fermentation unit.

12. The conductive intermediary member has a base and four or more protrusions projecting from the base. At least one of the multiple projections extends in a direction nonparallel to the plane passing through the tips of at least three other projections, One of the plurality of protrusions extends into the interior of one of the fermentation units and comes into contact with the microbial carrier within that fermentation unit. The fermentation apparatus according to claim 10, wherein the other protrusions among the plurality of protrusions extend into the interior of another fermentation unit located adjacent to the first fermentation unit and are in contact with the microbial carrier within the fermentation unit.

13. A cathode and an anode are arranged in the fermentation tank. The fermentation apparatus according to claim 8, configured such that an electric current path is formed including the cathode, the surface of the microbial carrier, and the anode.

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