JPH0411518Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a carrier for immobilizing microorganisms or enzymes.
In particular, it relates to a carrier for immobilizing microorganisms or enzymes suitable for fluidized bed bioreactors.

[Prior Art] In recent years, biological reactions using bioreactors have been widely adopted in the production of pharmaceuticals, alcohol, etc., and in the treatment processes of various industrial wastewaters and domestic wastewaters.

Reactions using bioreactors are usually carried out by filling a reaction tank with immobilized microorganisms or enzymes, or by dispersing and flowing them in the reaction tank, and then contacting the liquid to be treated. Let me go.

By the way, methods for immobilizing microorganisms on a carrier include an adhesion method and an entrapment method. The adhesion method is a method of trapping and immobilizing microorganisms in the pores of a porous material or the voids formed in an aggregate of fibers, and the entrapment method is a method of immobilizing microorganisms using PVA, polyacrylamide, agar, etc. This is a method in which microorganisms are immobilized enclosingly and made into beads or pellets.

On the other hand, enzyme immobilization methods are classified into carrier binding methods, crosslinking methods, and entrapment methods. Among these, carrier bonding methods are further divided into ionic bonding methods, covalent bonding methods, and physical adsorption methods, and DEAE cellulose, porous glass, activated carbon, etc. are used as carrier materials.

Conventionally, these carriers are known to have a granular shape such as a cube or a sphere, or a fibrous shape.

[Problems to be solved by the invention] However, the granular carriers used conventionally have a high specific gravity, and when carrying out biological treatment by dispersing microorganisms or enzyme-immobilized carriers in a reaction tank and making them flow. , its liquidity is extremely poor.
Therefore, in order to maintain a good flow state, the flow rate of the feed liquid must be increased, which is disadvantageous in terms of energy and equipment design. Moreover, even if the flow rate is adjusted, the carrier tends to settle in the corners of the reaction tank, making it difficult to uniformly disperse the carrier in the liquid in the reaction tank. Furthermore, there is a problem in that the life of the carrier is shortened due to wear caused by contact between the carriers.

Furthermore, fibrous materials tend to become entangled and form lumps.

[Means for Solving the Problems] The carrier of the present invention is made by covering a woven fabric, a nonwoven fabric, or a fiber aggregate with a net-like body.

[Function] The carrier of the present invention has a core made of woven fabric, non-woven fabric, or fiber aggregate wrapped in a net-like body, so it does not come into close contact with each other and is extremely lightweight, so it can easily absorb the liquid to be treated. It can flow freely inside.

Generally, when a carrier is used in a reaction tank for a long period of time, or when the flow rate of the liquid in the reaction tank is high, wear may occur due to collision or contact between the carriers, as described above. Furthermore, in the case of a fibrous carrier such as a woven or nonwoven fabric or a fiber aggregate, the fibers may unravel and fall apart during use.

However, in the carrier of the present invention, microorganisms or enzymes are mainly retained on the surface of the fibers in woven or nonwoven fabrics or fiber aggregates, or in the cavities formed by overlapping multiple fibers, and the microorganisms or enzymes are retained in the carrier. Since the portion is protected by the mesh, the above-mentioned disadvantages are avoided.

[Examples] Examples of the present invention will be described below with reference to the drawings.

FIGS. 1a and 1b are perspective views showing embodiments of the present invention, respectively.

The carrier 1 for immobilizing microorganisms or enzymes of the present invention is made by covering a woven or non-woven fabric or a fiber aggregate 2 with a net-like body 3.

There is no particular restriction on the shape of this woven fabric, nonwoven fabric, or fiber aggregate 3, but specifically, for example, the shape of the first
Examples include a cylindrical body as shown in FIG. In addition, various other shapes may be used, such as a cylindrical shape with a triangular or square cross-sectional shape. The shape of the woven fabric, non-woven fabric, or fiber aggregate is not limited to the above-mentioned hollow cylindrical shape, but may be solid, and may be cylindrical, prismatic, cubic, rectangular, spherical, or disc shaped. You can also do it.

In consideration of ease of manufacture, strength of the carrier, fluidity in liquid, etc., it is preferable to use a cylindrical body or a substantially cylindrical body as shown in FIGS. 1a and 1b.

In this case, there are no restrictions on the diameter, length, thickness, etc. of the cylinder of woven or nonwoven fabric or fiber aggregate, and it is determined as appropriate depending on the type and property of the microorganism or enzyme to be immobilized, the reaction tank, reaction mechanism, etc. Specifically, it is preferable that the cylinder has an outer diameter of 5 to 40 mm, an inner diameter of 2 to 35 mm, a length of 5 to 100 mm, a ratio of outer diameter to length of 2:1 to 1:5, and a thickness of 1 to 5 mm.

To manufacture such a carrier of the present invention, first, a woven or nonwoven fabric or fiber aggregate is formed into a desired shape. Examples of this method include a method of forming a woven fabric made of organic or inorganic fibers into a cylindrical shape. In this case, a so-called seamless tube that is woven into a cylindrical shape from the beginning may be cut to an appropriate length, or the fabric may be cut into a strip and both ends of the strip may be glued together to create a longer length. A tube may be manufactured and cut to the appropriate length.

In addition, continuous fibers of organic or inorganic substances are cut into appropriate lengths (usually 5 to 20 mm) and bonded together with an appropriate binder (adhesive) to form a nonwoven fabric, which is then formed into a cylindrical shape. It can be manufactured even if it is twisted.

In addition to this, there are other molding methods using nonwoven fabric.
After dispersing glass fibers of ~20 microns in water, paper is made using an appropriate binder, or a paper product is made and a binder is sprayed onto it to make a nonwoven fabric, which is then shaped into a cylinder. A method of doing so is also suitable. In this case, epoxy-based or acrylic-based binders are preferably used.

When molding such a nonwoven fabric, it is possible to arbitrarily adjust the thickness of the cylindrical wall portion of the resulting cylindrical carrier by adjusting the thickness of the fabric.

In the present invention, it is preferable that the woven fabric, nonwoven fabric, or fiber aggregate be formed to have a density of about 0.13 to 0.17 g/cm ³ from the viewpoint of liquid flowability, supporting performance, contact efficiency, etc.

Next, the woven fabric or nonwoven fabric or fiber aggregate formed in this way is covered with a net-like body.
In this case, for example, to obtain a carrier as shown in FIG. An example of this method is to simultaneously obtain a shape in which both ends are narrowed, but the method of enveloping with a net-like body is not limited to this.

As the material for the net-like body, heat-shrinkable resin is most preferable because of its ease of encapsulation, but other materials may be used as long as there is no risk of cracking or rusting. There is no particular limit to the size of this net-like body, but it is usually preferably about 0.5 to 4 mm.

The carrier of the present invention can be manufactured at low cost whether it is a woven fabric, a nonwoven fabric, or a fiber aggregate.
Moreover, mass production is possible.

In short, the material of the woven fabric or non-woven fabric or fiber aggregate constituting the carrier of the present invention is as follows:
Any material may be used as long as it can function as a carrier, and for example, various materials that have been conventionally used as carriers for immobilizing enzymes or microorganisms can be suitably employed.

[Effects of the Invention] As detailed above, the carrier for immobilizing microorganisms or enzymes of the present invention is made by encapsulating a woven fabric, a nonwoven fabric, or a fiber aggregate with a reticulated body, and has an extremely low specific gravity. Furthermore, they do not stick to each other and have good fluidity. Therefore, it is possible to maintain a good fluidity state even if the flow rate of the feed liquid is low without settling in the reaction tank. Furthermore, the carriers are not worn or damaged due to mutual contact or collision, and can withstand use for an extremely long period of time.

Therefore, according to the carrier of the present invention, it is possible to maintain good flow and contact conditions and carry out biological reactions with extremely high efficiency. Moreover, the carrier of the present invention is extremely advantageous because it can be industrially mass-produced at low cost and has excellent durability.

[Brief explanation of the drawing]

FIGS. 1a and 1b are perspective views showing an example of the carrier for immobilizing microorganisms or enzymes of the present invention. 1... Carrier for immobilizing microorganisms or enzymes, 2... Woven fabric or non-woven fabric or fiber aggregate, 3... Reticular body.

Claims (1)

[Claims for Utility Model Registration] (1) A carrier for immobilizing microorganisms or enzymes, which is made of a woven or nonwoven fabric or a fiber aggregate encapsulated in a network. (2) The carrier for immobilizing microorganisms or enzymes according to claim 1, wherein the woven fabric, nonwoven fabric, or fiber aggregate is formed into a cylindrical shape. (3) The woven fabric, nonwoven fabric, or fiber aggregate is formed into a substantially cylindrical shape constricted so that the diameter at both ends is smaller than the diameter at the center as stated in claim 1 of the utility model registration claim. A carrier for immobilizing microorganisms or enzymes. (4) The carrier for immobilizing microorganisms or enzymes according to any one of claims 1 to 3 of the utility model registration claim, wherein the network is made of resin. (5) The carrier for immobilizing microorganisms or enzymes according to claim 4 of the utility model registration, wherein the network is made of a heat-shrinkable resin.