JP2007209263A - Unit type carrier for microorganism of bioreactor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a unit type carrier for microorganism hard to form a narrow segment in filling to a bioreactor and easy to correct after filling. <P>SOLUTION: The unit type carrier for microorganism of bioreactor 1 comprises a plurality of hollow cylindrical microorganism carrier elements 20 installed on a predetermined position in a self standing rigid holding frame 10 having substantially the same height to the microorganism carrier element. A plurality of the microorganism carrier elements 20 are preferably filled in the rigid holding frame 10 in a way in which the carrier elements coherently come into contact with each other. Preferably the rigid holding frame 10 has a polygonal cross cut and the length of each side of the polygon is the multiple of the outside diameter of the carrier element 20. A position adjusting member is installed on the top end and/or bottom of the rigid holding frame 10 according to the needs. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a unit type microbial carrier of a bioreactor, and more particularly to a unit type microbial carrier used in a bioreactor that decomposes organic waste water, organic waste slurry, or the like with microorganisms. The present invention can be effectively used as a fixed bed of methane fermentation microorganisms used for a long time in a bioreactor.

  Organic treatment liquids such as organic waste water and organic waste slurry are guided to a bioreactor (biological treatment tank) equipped with a fixed bed of microorganisms, brought into contact with microorganisms attached to the fixed bed, and decomposed by the digestive action of the microorganisms. Biological treatment to be processed is performed. From the viewpoint of improving processing efficiency, the fixed bed in the bioreactor can attach microorganisms at a high concentration, resulting in deformation that reduces the contact efficiency with the processing liquid and clogging with solids such as processing liquid residues and surplus microorganisms. It is required to satisfy conditions such as difficulty.

  As shown in FIG. 3, the present inventors set the porous hollow cylindrical body 21 formed of glass fiber woven or non-woven fabric as a synthetic floor satisfying these conditions. A microbial carrier element 20 supported by a frame 22 made of a member was developed and disclosed in Patent Document 1. This microbial carrier element 20 can capture microorganisms at a high concentration in the pores of the woven or non-woven fabric of the hollow cylindrical body 21, and the inner diameter of the hollow cylindrical body 21 while taking into consideration the microbial adhesion surface area. By adjusting the resistance, the resistance to the solids in the treatment liquid can be reduced to prevent clogging. Further, even when a large number of carrier elements 20 are stacked, the lower carrier element 20 is not deformed due to the shape retaining ability of the frame 22.

In addition, the present inventors have found that carbon fiber is more suitable than glass fiber as a material for the carrier element 20 of methane fermentation microorganisms to be fixed in the bioreactor for a long time, and disclosed in Patent Document 2. When used for a long time in a bioreactor that is easily acidified by organic acids generated during the methane fermentation process, the glass fiber microbial carrier element 20 deteriorates (weakens) the strength of the glass fiber due to the acidified treatment liquid, and deforms. And problems that caused blockage were experienced. The microbial carrier element 20 made of carbon fiber has a high resistance to acid and a large amount of attached microorganisms per unit area. Therefore, even when used for a long time in a bioreactor that is easily acidified, the microbial carrier element 20 does not easily deform or clog. An example of the carbon fiber is a fiber obtained by melt spinning a coal pitch at a high temperature to convert it into an infusible carbon, preferably a thickness of 0.3 to 6.0 mm made of carbon fiber having a diameter of 1 to 30 μm, and a unit weight of 20 to 300 g / m ^2. The hollow cylindrical body 21 of the microorganism carrier element 20 is formed of the carbon fiber non-woven fabric.

  The microbial carrier elements 20 of Patent Documents 1 and 2 are, for example, one by one as shown in FIG. 4 or a bundle of several to 10 pieces with a string 24, and a bioreactor through a manhole 3 as shown in FIG. Carry into 2 and align regularly with the axis to make a fixed bed. If the inner diameter of the hollow cylindrical body 21 is too small, there is a risk of clogging, and if it is too large, the surface area for attaching microorganisms will be insufficient. For example, a microorganism carrier element 20 having an inner diameter of about 10-100 mm is regularly packed in the bioreactor 2. Thus, it is possible to provide a fixed bed having a sufficiently high concentration of microorganisms and hardly clogging. Reference numeral 5 in the figure indicates a perforated cradle on which the microorganism carrier element 20 is placed, and reference numeral 6 indicates a perforated lid for preventing the microorganism carrier element 20 from being lifted.

Japanese Utility Model Publication No. 7-021280 Japanese Patent No. 3470944

  However, in the microbial carrier element 20 of Patent Documents 1 and 2, when considering the workability of loading and filling into the bioreactor 2, the length of one microbial carrier element is limited to 2 to 3 m, and the tall and large bioreactor 2 In the case of a fixed bed, a plurality of microbial carrier elements 20 need to be stacked in a plurality of stages (three stages in the illustrated example) with their upper and lower axes aligned as shown in FIG. The operation of stacking a large number of microbial carrier elements 20 as described above is very troublesome and has a problem in that a portion (hollow constriction portion) in which the upper and lower axes are partially shifted and the inner diameter becomes narrow is easily generated. If a hollow constriction portion is generated, solid matter in the treatment liquid is likely to be deposited, which causes the fixed bed to be blocked. In addition, it is difficult to repair only the closed portion of the fixed bed on which a large number of microbial carrier elements 20 are stacked, even if a partial blockage occurs. There is also a problem that has to be reloaded.

  Conventionally, a partition member 9 that divides the interior of the bioreactor 2 into compartments having appropriate cross-sectional areas as shown in FIG. Yes. The partition member 9 in the illustrated example is obtained by projecting a metal rod or the like radially from a column member 9a supported on the bottom plate 4 of the bioreactor 2, and filling / restoring the microbial carrier element 20 in a partition unit partitioned by the metal rod. Is possible. However, since the partition member 9 complicates the structure of the bioreactor 2 and reduces the effective internal volume of the bioreactor 2, the number of partitions partitioned by the partition member 9 is limited. Even if the partition member 9 is used, it is difficult to effectively prevent the deviation of the axis line when the microorganism carrier elements 20 are stacked. In order to use the microbial carrier element 20 of Patent Documents 1 and 2 as a fixed bed of a large bioreactor 2, a large number of microbial carrier elements 20 are filled so that no constriction occurs, and only a part is filled after filling. It must be easy to repair.

  Therefore, an object of the present invention is to provide a unit-type microbial carrier that is less likely to cause a constriction when filling a bioreactor and that is easy to repair after filling.

  Referring to the embodiment of FIG. 1, a unit type microbial carrier 1 of a bioreactor according to the present invention has a plurality of hollow cylindrical microbial carrier elements 20 (see FIG. 3) having substantially the same height as the carrier element 20. The self-supporting rigid holding frame 10 is loaded while being positioned at a predetermined position.

  Preferably, a plurality of microbial carrier elements 20 are filled in the rigid holding frame 10 in close contact with each other. More preferably, the rigid holding frame 10 has a polygonal cross section, and each side of the polygonal cross section is an integral multiple of the outer diameter of the carrier element 20. An alignment member can be provided on the upper end and / or the lower end of the rigid holding frame 10 as necessary.

  Since the unit type microbial carrier 1 of the bioreactor of the present invention is loaded while positioning a plurality of hollow cylindrical microbial carrier elements 20 at predetermined positions within the self-supporting rigid holding frame 10, the following remarkable effects are exhibited. .

(A) A plurality of microbial carrier elements 20 can be simultaneously aligned and stacked by aligning the rigid holding frame 10 in the vertical direction, and a fixed bed without a narrowed portion of the inner diameter due to the deviation of the vertical axis of the carrier element 20 can be formed. Can be easily formed.
(B) The self-supporting unit type microbial carrier 1 can be laminated to form a fixed bed. When a part of the fixed bed is blocked, only the unit of the blocked part can be easily replaced.
(C) In addition, it is not necessary to provide a partition member for preventing the inclination of the microorganism carrier element 20 in the bioreactor, and the structure of the bioreactor can be simplified and the internal volume can be effectively used.
(D) For example, several tens to several hundreds of microorganism carrier elements 20 can be used as a unit, and the fixed bed can be filled and restored in units. Work efficiency can be greatly improved compared to the method.
(E) If a microbial carrier element is loaded into a rigid holding frame in a manufacturing factory to form a unit type microbial carrier, the carrier element can be prevented from being damaged during transportation by the rigid holding frame, and the carrier element is prevented from being damaged. No packaging material such as film is required.

  FIG. 1 shows an embodiment of a unit type microbial carrier 1 of the present invention (hereinafter sometimes referred to as a unit 1) in which a plurality of microbial carrier elements 20 are loaded in a rigid holding frame 10. As shown in FIG. 3, the microbial carrier element 20 of the illustrated example comprises a porous hollow cylindrical tubular body 21 having an outer diameter of 90 mm and a length of 2000 mm formed of a woven or non-woven fabric of glass fiber or carbon fiber. It is supported by a frame 22 made of a synthetic resin circumferential and axial member. For example, in the bioreactor 2 that performs methane fermentation, it is known that microorganisms are easily separated from the carrier element 20 by a gaseous product generated in the fermentation process. However, a woven or non-woven fabric of glass fiber or carbon fiber is interposed between the fibers. Capturing anaerobic microorganisms makes it difficult for the microorganisms to peel off, and can effectively increase the amount of microorganisms per unit area. Further, as described above, since the carbon fiber cloth has little strength deterioration in the acidic solution, the anaerobic microorganisms can be stably supported over a long period of time in the bioreactor 2 that is particularly easily acidified.

The illustrated example of the rigid holding frame 10 includes a rectangular (square) bottom end frame member 13 and a top end frame member 14 each having a side of 990 mm, and four column frame members 15 having a height of 2000 mm for joining the both end frame members 13 and 14 together. A rectangular parallelepiped having a volume of about 2 m ³ and capable of being self-supported by the bottom end frame member 13. The holding frame 10 is not limited to a rectangular cross section, but may be an appropriate cross sectional shape that can be aligned in the vertical direction, for example, a polygon (regular polygon). The material of each of the frame members 13, 14 and 15 is, for example, a steel round bar having a diameter of 6 mm or an equilateral mountain type steel, but may be a steel pipe or the like, and thicker if a material or coating that does not easily corrode in the bioreactor 2 is provided. There is no particular limitation on the shape and the like. Preferably, the top end frame member 14 has an equilateral mountain shape so that the bottom end frame member 13 of the upper unit 1 can be stably placed on the top end frame member 14 of the lower unit 1. When the holding frame 10 becomes heavy, it is necessary to increase the strength, and the manufacturing and transportation costs increase. Therefore, a lightweight material is desirable.

  Further, as shown in FIG. 1C, a porous wall having a large number of voids smaller than the outer diameter of the microorganism carrier element 20 on the bottom surface of the rigid holding frame 10 to support the microorganism carrier element 20 loaded in the holding frame 10. 11 (in the illustrated example, a grating made of steel round bars arranged at intervals of about 76 mm) can be provided. If necessary, a porous lid (not shown) for preventing the carrier element 20 from floating may be provided on the top surface of the rigid holding frame 10. If a perforated lid is provided on the top surface of the rigid holding frame 10, the perforated lid 6 in the bioreactor 2 described later can be omitted. When it is necessary to reinforce the rigid retaining frame 10, the beam frame member 12 is provided at about two places (for example, 300 mm from the top and bottom ends) of the middle part of the column frame member 15 as shown in the example of the figure. Can do. The beam frame member 12 also functions to prevent the microbial carrier element 20 loaded in the rigid holding frame 10 from slipping out of the frame.

  Inside the unit type microbial carrier 1, as shown in FIG. 1 (B), the microbial carrier elements 20 can be in close contact with each other and arranged in 11 rows in length and breadth, and 121 (11 × 11) can be loaded. Each side of the rectangular cross section of the holding frame 10 is an integral multiple of the outer diameter of the cylindrical microorganism carrier element 20, and the microorganism carrier elements 20 are in close contact with each other to regularly fill the holding frame 10, thereby each microorganism carrier. The axis of the element 20 can be positioned with respect to the holding frame 10. The cylindrical microbial carrier element 20 can provide a sufficient gap even when closely attached to each other, and therefore has an advantage that the gap is hardly blocked. However, the microorganism carrier element 20 is not limited to a cylindrical shape as long as it can be positioned with respect to the holding frame 10, and the microorganism carrier element 20 is positioned at a predetermined position in the holding frame 10 using an appropriate positioning member or the like. Also good.

  As shown in FIG. 2, the unit type microbial carrier 1 of the illustrated example is carried into the bioreactor 2 through the manhole 3, and is vertically moved with the four corners of the bottom end frame member 13 and the top end frame member 14 as alignment parts. Accurately stack multiple items so that they do not slip. Since the axis of each loaded microorganism carrier element 20 is positioned with respect to the holding frame 10, the axes of the carrier elements 20 can be simultaneously and easily aligned by the vertical alignment of the holding frame 1. it can. Further, if the rigid holding frame 10 has a regular polygonal cross section, regardless of the direction of each unit 1, the position of each carrier element 20 is adjusted by the alignment of the bottom and top corners (the alignment of the axis of the holding frame 10). It is possible to align the axis. If necessary, the bottom end frame member 13 and the top end frame member 14 may be provided with an alignment member (for example, a protrusion) and a coupling member for coupling the holding frame 10 to each other.

  That is, according to the unit type microbial carrier 1 of the present invention, the bioreactor 2 can be filled while positioning a large number of microbial carrier elements 20 in an orderly manner, so that the working time can be greatly reduced as compared with the conventional filling method. Further, since the vertical axis of the microbial carrier element 20 to be laminated is almost eliminated and a narrowed portion of the inner diameter is hardly generated, it is possible to effectively prevent the fixed bed from being blocked. Further, since the self-supporting units 1 are laminated to form a fixed bed, even when the fixed bed is blocked, only the blocked unit 1 can be taken out from the bioreactor 2 through the manhole 3, and a part of the fixed bed Repair becomes easier.

  Thus, it is possible to achieve the object of the present invention, which is “a unit type microbial carrier that is less likely to cause a constriction when filled into a bioreactor and is easy to repair after filling”.

  FIG. 2 shows a plan view and a cross-sectional view of a bioreactor 2 having an inner diameter of about 6 m filled with the unit type microbial carrier 1 of the present invention. In the illustrated example, a perforated cradle (grating) 5 for unit placement is provided at the bottom of the bioreactor 2, and the units 1 loaded from the manhole 3 are closely attached to each other on the cradle 5 and stacked in two stages. . Since the unit 1 having a rectangular cross section cannot be spread over the entire area of the cradle 5, as shown in FIG. 5B, only the microorganism carrier element 20 is provided on the peripheral portion of the cradle 5 where the unit 1 cannot be placed. Similarly, regular packing is performed to form a fixed bed as shown in FIG. The cross-sectional shape and size of the unit 1 can be devised so that the unit 1 can be spread over as wide a range as possible. Further, in order to fill the peripheral portion of the cradle 5, a unit 1 such as a sectional fan may be used. Further, a perforated lid (grating) 6 for preventing the unit 1 and the microorganism carrier element 20 from floating is provided on the upper part of the fixed floor.

  By using the unit type microbial carrier 1 of the present invention as shown in FIG. 2 as a fixed bed of the bioreactor 2, there is no need to provide a partition member 9 for preventing the inclination of the microbial carrier element 20 as shown in FIG. The structure of the bioreactor 2 can be simplified, and the efficiency of the microbial reaction can be expected to increase by increasing the carrier filling rate in the bioreactor 2. Conventionally, when the microbial carrier element 20 is transported from the manufacturing plant to the on-site bioreactor 2, the entire microbial carrier element 20 must be packed with a synthetic resin film so that the microbial carrier element 20 is not damaged. It has been pointed out that the removal work takes time and the packaging film becomes a new waste. According to the unit type microbial carrier 1 of the present invention, the microbial carrier element 20 can be transported to the on-site bioreactor 2 after being loaded into the rigid holding frame 10 in the manufacturing factory. Since the breakage can be prevented by the rigid holding frame 10, a packing material for preventing the breakage of the carrier element 20 is not necessary.

It is explanatory drawing of one Example of the unit type microorganism carrier by this invention. It is explanatory drawing of the loading method to the bioreactor of a unit type microbial support | carrier. It is explanatory drawing of an example of a microorganism carrier. It is explanatory drawing of how to bundle the conventional microorganisms carrier. It is explanatory drawing of the loading method to the bioreactor of the conventional microbial support | carrier. It is explanatory drawing of the inclination prevention method in the bioreactor of the conventional microorganism carrier.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Unit type microorganism carrier 2 ... Bioreactor 3 ... Manhole 4 ... Bottom plate 5 ... Perforated cradle 6 ... Perforated lid 9 ... Partition member 9a ... Column member
10 ... Rigid holding frame 11 ... Perforated wall
12 ... Beam frame member 13 ... Bottom end frame member
14… Top frame member 15… Column frame member
20 ... Microorganism carrier element 21 ... Hollow cylindrical body
22 ... Frame 24 ... Bundled string

Claims (7)

  A unit type microbial carrier for a bioreactor in which a plurality of hollow cylindrical microbial carrier elements are loaded while being positioned at predetermined positions in a self-supporting rigid holding frame having substantially the same height as the carrier element.   2. The microbial carrier according to claim 1, wherein the plurality of microbial carrier elements are packed in close contact with each other in a rigid holding frame.   The microbial carrier according to claim 1 or 2, wherein the rigid holding frame has a polygonal cross section, and each side of the polygonal cross section is an integral multiple of the outer diameter of the carrier element.   4. The microbial carrier according to claim 1, wherein an alignment member is provided on the upper end and / or the lower end of the rigid holding frame.   5. The microbial carrier according to claim 1, wherein a porous wall for supporting the carrier element is provided on the bottom surface of the rigid holding frame.   6. The microbial carrier according to claim 1, wherein a porous lid for preventing the carrier element from being lifted is provided on the top surface of the rigid holding frame.   The microbial carrier according to any one of claims 1 to 6, wherein the microbial carrier element is a unit type microbial carrier of a bioreactor obtained by forming a woven or non-woven fabric of glass fiber or carbon fiber into a cylindrical shape.

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