JP4346206B2 - Enzyme or microorganism-immobilized carrier mixture and water treatment method using the same - Google Patents

Description

【００５９】
【発明の効果】
本発明の固定化担体混合物により、流動床型バイオリアクタなどの水中における微生物固定化担体の浮上、流出を防止することができるとともに、水中における微生物固定化担体の流動性を確保することができる。
【００６０】
また、本発明の微生物固定化担体混合物を用いた水処理システムにより、担体の浮上・流出防止と十分な流動性の確保の両立が可能であり、本発明の水処理システムは、特に曝気によって担体の浮上や流出が起こりやすい硝化槽においてその効果を大きく発揮させることができる。なかでも５０人以下の人数における屎尿および／又は生活雑廃水を処理の対象とした比較的小規模な処理システムにおいては浮上・流出の問題は技術的・コスト的に解決が難しいため、本発明の水処理システムを適用する利点が大きい。
【図面の簡単な説明】
【図１】担体流動試験装置の概要を示す概要図（側面断面図、上面からの概要図）である。
【図２】担体流出防止性評価時における担体流動試験装置の概要図である。
【図３】担体流動性評価時における担体流動試験装置の概要図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an enzyme or microorganism-immobilized carrier mixture that is prevented from floating and flowing out in water, such as a fluidized bed bioreactor, and a water treatment system using the immobilized carrier mixture.
[0002]
[Prior art and problems]
It has been well known that water treatment methods such as waste water can save space, improve processing capacity, and improve processing stability in a low temperature period by using a microorganism-immobilized carrier. However, particularly in a small water treatment facility, there is a problem that the carrier is likely to float and flow out when separating the treated water and the microorganism-immobilized carrier. As one of the solutions, for example, it is conceivable to suppress the floating / outflow of the carrier by increasing the sedimentation rate of the microorganism-immobilized carrier, but this method reduces the fluidity of the carrier in water. The problem arises.
[0003]
In water treatment using a microorganism-immobilized carrier, as a technique for preventing the microorganism-immobilized carrier from flowing out, there is a method using a net or a wedge wire screen, but sludge and contaminants are clogged with a method using a net. There is a problem, and the method using the wedge wire screen has a drawback that the total cost of the system is increased because the wedge wire screen is expensive.
[0004]
The main object of the present invention is to prevent floating or outflow of an enzyme or a microorganism-immobilized support in water such as a fluidized bed bioreactor, and to ensure fluidity of the enzyme or microorganism-immobilized support in water. Another object is to provide a water treatment method that can prevent immobilization and outflow of an enzyme or a microorganism-immobilized carrier, and can ensure fluidity in water of the microorganism-immobilized carrier.
[0005]
[Means for Solving the Problems]
As a result of intensive studies to achieve the above object, the present inventors have used a mixture of two or more specific enzymes or microorganism-immobilized carriers that have different sedimentation rates of 0.4 cm / second or more. It has been found that by providing a gradient in the distribution in the fluid tank, sufficient fluidity can be ensured while preventing the carrier of the oxidizing carrier from floating and flowing out, and the present invention has been completed.
[0006]
  Thus, according to the present invention, (A) the sedimentation rate in water is4.2-10cm /Second enzyme immobilization carrier orThe microorganism-immobilized carrier and (B) the sedimentation rate in water0.8-3.0cm /In secondsYes, and theEnzyme immobilization carrier or0.4 cm / sec or less smaller than the sedimentation rate of the microorganism-immobilized carrier (A)Enzyme immobilization carrier orConsisting of a mixture of microbial immobilization carriers,The solidWith the support (A)The solidEnzyme in which floating and outflow in water are prevented, characterized in that the volume ratio of the carrier to the regularizing carrier (B) is in the range of 20/80 to 90/10 as (A) / (B)Immobilization carrierAlternatively, a microbial immobilization carrier mixture is provided.
[0007]
  Further, according to the present invention, (A) the sedimentation rate in water is4.2-10cm /Second enzyme immobilization carrier orThe microorganism-immobilized carrier and (B) the sedimentation rate in water0.8-3.0cm /In secondsYes, and theEnzyme immobilization carrier or0.4 cm / sec or less smaller than the sedimentation rate of the microorganism-immobilized carrier (A)Enzyme immobilization carrier orConsisting of a mixture of microbial immobilization carriers,The solidWith the support (A)The solidAn enzyme characterized in that a carrier mixture having a carrier volume ratio with the regularizing carrier (B) in the range of 20/80 to 90/10 in terms of (A) / (B) is used as a carrier for water treatment.Immobilization carrierAlternatively, a water treatment method using a microorganism-immobilized carrier is provided.
[0008]
Hereinafter, the immobilized carrier mixture and the water treatment method of the present invention will be described in more detail.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The enzyme or microorganism-immobilized carrier used in the method of the present invention (hereinafter sometimes abbreviated as “carrier”) is not particularly limited in its material, shape and the like as long as the sedimentation rate can be controlled. For example, (1) hydrophilic polymer gel such as ethylene glycol gel or polyvinyl alcohol gel; (2) (a) hydrophilic photocurable resin having at least two ethylenically unsaturated bonds in one molecule; An aqueous liquid composition comprising (b) a photopolymerization initiator and (c) a water-soluble polymeric polysaccharide capable of gelation by contact with an alkali metal ion or a polyvalent metal ion, The composition is dropped into an aqueous medium containing a valent metal ion to gel the composition, and then the resulting granular gel is irradiated with actinic rays to cure the photocurable resin in the granular gel. Photocuring gel that; ▲ 3 ▼ (d) inorganic powder or granular material in these gels, can include those formed by incorporating a specific gravity adjusting agent such as (e) inorganic-based micro hollow beads.
[0010]
Among these, the photocuring gel (2) and the photocuring gel (2) containing a specific gravity adjusting agent can be preferably used.
[0011]
Hereinafter, the photocurable gel {circle around (2)} that can be preferably used and the carrier containing a specific gravity adjusting agent in the photocured gel {circle around (2)} will be described.
[0012]
Hydrophilic photocurable resin (a):
The hydrophilic photocurable resin which is the component (a) for producing the photocurable gel (2) is a hydrophilic photocurable resin having at least two ethylenically unsaturated bonds in one molecule. An ionic or nonionic hydrophilic group having an average molecular weight of 300 to 30,000, preferably 500 to 20,000, sufficient to disperse in water, such as a hydroxyl group, a carboxyl group, a phosphate group, or a sulfonic acid Preferred are those having a group, an amino group, an ether bond, etc. in the molecule and cured to a substantially water-insoluble resin when irradiated with an actinic ray having a wavelength of about 200 to 600 nm. used.
[0013]
As such a photo-curing resin, those known for immobilization carriers of enzymes or microbial cells can be used (for example, Japanese Patent Publication No. 55-40, Japanese Patent Publication No. 55-20676, Japanese Patent Publication No. 55-20676). As representative examples thereof, high acid value unsaturated polyesters, high acid value unsaturated epoxides, anionic unsaturated acrylic resins, cationic unsaturated acrylic resins, Polyesters of polyethylene glycol and / or polypropylene glycol and (meth) acrylic acid, polyethylene glycol and / or polypropylene glycol and 2-hydroxyethyl (meth) acrylate are diisocyanates such as tolylene diisocyanate, xylylene diisocyanate and isophorone diisocyanate. Bonded through compounds Urethanization adducts, unsaturated celluloses, unsaturated polyamides, and the like. The photocurable resins as exemplified above can be used alone or in combination of two or more. Among these photocurable resins, those that can be particularly preferably used in the present invention include urethanated adducts of polyethylene glycol and / or polypropylene glycol and 2-hydroxyethyl (meth) acrylate.
[0014]
Photopolymerization initiator (b):
A photoinitiator (b) is mix | blended in order to accelerate | stimulate the photopolymerization reaction of the said hydrophilic photocurable resin (a). Photopolymerization initiators that can be used are those that decompose upon light irradiation to generate radicals, which become polymerization initiation species and cause a crosslinking reaction between the photocurable resins. For example, benzoin, acetoin Α-carbonyl alcohols such as; benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, anisoin ethyl ether, and acyloin ethers such as pivaloin ethyl ether; polycyclic aromatic compounds such as naphthol and hydroxyanthracene; Α-substituted acyloins such as methylbenzoin and α-methoxybenzoin; azoamide compounds such as 2-cyano-2-butylazoformamide; metal salts such as ferric chloride; mercaptans, disulfides, halogen compounds, dyes And the like.
[0015]
Water-soluble polymer polysaccharide (c):
The water-soluble polymer polysaccharide (c) is a water-soluble polymer capable of changing to a water-insoluble or sparingly soluble gel when contacted with an alkali metal ion or a polyvalent metal ion in an aqueous medium. A polysaccharide having a number average molecular weight generally in the range of about 3,000 to 2,000,000, in particular 5,000 to 1,000,000, and an alkali metal ion or polyvalent metal ion; Those having a solubility of usually at least about 10 g / l (25 ° C.) in a water-soluble state before contact are preferably used.
[0016]
Specific examples of the water-soluble polymeric polysaccharide having such properties include alkali metal salts of alginic acid, carrageenan and the like.
[0017]
These water-soluble polymeric polysaccharides are dissolved in an aqueous medium, in the case of carrageenan, by contacting with an alkali metal ion such as potassium ion or sodium ion, and in the case of an alkali metal salt of alginic acid, Contact with at least one polyvalent metal ion of alkaline earth metal ions such as magnesium ion, calcium ion, strontium ion and barium ion; or other polyvalent metal ions such as aluminum ion, cerium ion and nickel ion Can be gelled.
[0018]
Preparation of photocured gel (2):
The photocuring gel (2) is prepared, for example, by mixing an aqueous liquid composition containing the components (a), (b) and (c) in an aqueous medium containing alkali metal ions or polyvalent metal ions. It can be done by dripping and granulating and curing it.
[0019]
The mutual use ratios of the components (a), (b) and (c) are not strictly limited and can vary widely depending on the type of each component, but in general, (a) It is appropriate to use the components (b) and (c) in the following proportions with respect to 100 parts by weight of the component hydrophilic photocurable resin.
[0020]
Photopolymerization initiator (b): 0.5 to 5 parts by weight, preferably 1 to 3 parts by weight,
Water-soluble polymer polysaccharide (c): 0.5 to 15 parts by weight, preferably 1 to 8 parts by weight.
[0021]
An aqueous liquid composition is prepared by dissolving or dispersing the components (a) to (c) described above in an aqueous medium. The solid content concentration of the liquid composition is generally 5 to 30% by weight, particularly 8 to 25% by weight. When the carrier contains a specific gravity adjusting agent such as (d) inorganic powder and (e) inorganic micro hollow beads in the photocuring gel (2), the above (a) to ( A specific gravity adjuster may be further contained in the aqueous liquid composition containing the component c).
[0022]
The aqueous liquid composition thus prepared is then dripped into an aqueous medium containing the above-mentioned types of alkali metal ions or polyvalent metal ions, thereby causing the liquid composition to form a gel. It is done. The concentration of alkali metal ions or polyvalent metal ions that cause gelation varies depending on the type of water-soluble polymeric polysaccharide, but generally ranges from 0.01 to 5 mol / l, preferably from 0.05 to 3 mol / l. Is within.
[0023]
The dropping of the aqueous liquid composition into the aqueous medium containing the alkali metal ion or the polyvalent metal ion is performed by, for example, a method of dropping the liquid composition from the tip of a syringe or the liquid composition using centrifugal force. It can be carried out by a method such as a method of scattering in a granular form, a method of atomizing the liquid composition from the tip of a spray nozzle and dropping it into a granular form. The size of the droplet to be dropped can be freely changed depending on the particle size desired for the carrier for immobilizing an enzyme or microorganism, but usually the diameter is about 0.1 mm to about 5 mm, preferably about 0. Conveniently, it is dropped as droplets in the range of 5 mm to about 4 mm.
[0024]
The granular gel produced as described above is directly dispersed in an aqueous medium or separated from the aqueous medium, and then irradiated with actinic rays to give a hydrophilic photocurable resin in the granular gel. Allow to cure. As a result, the granular gel is substantially insoluble in water, and a granular molded product for immobilizing an enzyme or microorganism can be obtained.
[0025]
The wavelength of the actinic ray that can be used for the above photocuring varies depending on the type of the photocurable resin contained in the granular gel, but in general, light having a wavelength in the range of about 250 to about 600 nm is used. It is advantageous to use a light source that emits for irradiation. Examples of such a light source include a low-pressure mercury lamp, a high-pressure mercury lamp, a fluorescent lamp, a xenon lamp, a carbon arc lamp, and sunlight. The irradiation time needs to be changed according to the light intensity of the light source, the distance from the light source, etc., but can generally be in the range of about 0.5 to about 10 minutes.
[0026]
The granular gel thus subjected to the irradiation treatment can be washed with water or an aqueous buffer solution and stored as such or lyophilized.
[0027]
  The immobilization carrier mixture that is prevented from floating and flowing out according to the present invention has a sedimentation rate in water of 3.3 cm / second or more, preferably 4.2 to 10 cm / second.Burden ofBody (A) and a sedimentation rate in water of 0.5 cm / sec or more, preferably 0.8 to 3.0 cm /In secondsYes, orBearing0.4 cm / sec or less smaller than the body (A), preferably 0.6 cm / sec or less smallerIIt consists of a body (B).
[0028]
When the sedimentation rate of the carrier (A) is smaller than 3.3 cm / second, it is difficult to suppress the floating and outflow of the carrier when separating the treated water and the microorganism-immobilized carrier. Further, when the difference between the sedimentation rate of the carrier (B) and the sedimentation rate of the carrier (A) is less than 0.4 cm / second, a carrier distribution gradient is not formed in the tank, and sufficient fluidity cannot be secured. Tend.
[0029]
Examples of the method for controlling the sedimentation rate of the carrier (A) and the carrier (B) in water include adjustment of the carrier specific gravity, adjustment of the carrier particle diameter, and control of the carrier shape. Adjustment and adjustment of the carrier particle size can be easily performed.
[0030]
The specific gravity of the carrier can be adjusted by adjusting the solid content concentration of the carrier, but a preferable method in terms of the strength and durability of the carrier is by blending various specific gravity adjusting agents. When a specific gravity adjusting agent is blended, the particle size of the specific gravity adjusting agent is preferably 80 μm or less from the viewpoint of workability during the production of the carrier. The amount of the specific gravity adjusting agent to be added varies depending on the type, but in general, it is preferably 120 parts by weight or less with respect to 100 parts by weight of the total solid content of the carrier from the viewpoint of carrier strength and durability.
[0031]
The specific gravity adjusting agent used for adjusting the specific gravity of the carrier (A) is usually preferably one that increases the specific gravity of the carrier (A) to increase the sedimentation rate of the carrier, and the specific gravity is 1.9 or more, preferably 2 Examples include inorganic powders (d) that are insoluble or sparingly soluble in water in the range of 0.0 to 4.5, such as heavy calcium carbonate, clay, white carbon, talc, barium carbonate, and oxalic acid. Various pigments such as aluminum, alumina, mica powder, silica (silica sand, meteorite powder) powder; colloidal silica, fine glass beads, etc., specifically, “Hi-micron HE-5” (manufactured by Takehara Chemical Industries, Ltd., Talc, specific gravity 2.67), "micro mica MK-100" (manufactured by Co-op Chemical, mica powder, specific gravity 2.7), "unibeads UB-03L", "same UB-23L", "same UB-34L" (More As for the deviation, Glass Co., Ltd. manufactured by Union Co., Ltd., specific gravity 2.5), “MB-20” (manufactured by Toshiba Barotini Co., Ltd., glass beads, specific gravity 2.5) can be used.
[0032]
On the other hand, the specific gravity adjusting agent used for adjusting the specific gravity of the carrier (B) is usually preferably one that reduces the specific gravity of the carrier (B) to reduce the sedimentation rate of the carrier, and has a specific gravity of 0.2 to 0.8. Preferably, a completely closed inorganic micro hollow bead (e) of 0.3 to 0.6 is suitable. When the specific gravity adjusting agent for the carrier (B) has a specific gravity of less than 0.2, production problems such as easy separation will easily occur when added to the carrier, while the specific gravity is 0.9. If it exceeds, the effect of reducing the specific gravity of the carrier will be reduced. Specific examples of the specific gravity adjusting agent for the carrier (B) include hollow glass beads and hollow celite. Specifically, “Filite 200/7”, “300/7” (all of which are Nippon Ferrite Co., Ltd.) Manufactured, hollow glass beads, specific gravity 0.7), “Santurite Y02”, “Same Y04”, “Same Y0C” (all from Sanki Kogyo Co., Ltd., hollow Celite), “Fuji Balloon S-35”, “S-40”, “S-45”, “H-30”, “H-35”, “H-40X” (all of these are hollow glass beads manufactured by Fuji Silysia Chemical Ltd.), “Q-Ce1570” (manufactured by Toshiba Barotini Co., Ltd., hollow glass beads, specific gravity 0.34) can be used.
[0033]
Adjustment of the carrier particle size for controlling the sedimentation rate of the carrier is, for example, in the case of forming gelled particles by dropping the liquid composition and gelling in the liquid, such as in the production of photocured gel (2). By adjusting the inner diameter of the nozzle used when dropping the liquid composition, it can usually be easily adjusted within the range of 2.5 mm to 5.4 mm. In order to increase the sedimentation rate, the particle size is increased. To decrease the sedimentation rate, the particle size may be decreased.
[0034]
In order to control the sedimentation rate of the carrier, individual methods of adjusting the specific gravity of the carrier and adjusting the particle size of the carrier can be used, but these methods can be combined and other methods can be used. It may be used.
[0035]
Enzymes or microorganisms are attached to or included in each enzyme or microorganism-immobilized carrier of the carriers (A) and (B). The enzyme or microorganism that can be attached or entrapped is not particularly limited, and can be used depending on the purpose. Representative examples of the enzymes include lactate hydrogenase (1 · 1 · 2 · 3), lipase (3 · 1.1.3), cholesterol esterase (3 · 1 · 1 · 13), β-galactosidase (3 · 2.1.23), A.I. T.A. P. Examples include ase (3, 6, 1, 3). In addition, as the above-mentioned microorganism, either an anaerobic microorganism or an aerobic microorganism can be used. Examples include yeasts such as Candida; bacteria such as Zymomonas, Nitrosomonas, Nitrobacter, Paracoccus, Vibrio, Methanosarcina, and Bacillus.
[0036]
In order to attach these enzymes or microorganisms to a carrier, the carriers and the enzymes or microorganisms can be attached to the surface of the carrier by bringing them into contact with a liquid such as water. In the case where enzymes or microorganisms are preliminarily immobilized and immobilized in a carrier, for example, the carrier is a photocuring gel (2) or a photocuring gel (2) containing a specific gravity adjusting agent. In addition, an enzyme or a microorganism can be mixed and immobilized in an aqueous liquid containing the components (a), (b), (c) and, if necessary, a specific gravity adjusting agent.
[0037]
In the water treatment using the carrier mixture of the present invention, for example, an enzyme or a microorganism-immobilized carrier mixture is added to water to be treated such as waste water in a container or a tank, and air is blown to increase the oxygen concentration in the water, followed by stirring. It can be carried out by a method such as decomposing by contacting a substrate with an enzyme or a microorganism on the carrier by aeration.
[0038]
The mixing ratio of the carrier (A) and the carrier (B) in the enzyme or microorganism-immobilized carrier mixture of the present invention is 20/80 to 90/10 in volume ratio of carrier (A) / carrier (B), preferably It can be set within the range of 35/65 to 80/20. As a result, the carrier can be prevented from floating and flowing out, and sufficient carrier fluidity can be ensured. When the volume ratio of the carrier (A) is lower than the above ratio, the carrier tends to float and flow out. On the other hand, when the volume ratio of the carrier (A) is higher than the above ratio, sufficient fluidity of the carrier in water is obtained. There is a tendency to disappear. 1 type of said support | carrier (A) may be sufficient, and what combined 2 or more types may be sufficient. Further, the carrier (B) may also be one kind or a combination of two or more kinds.
[0039]
The carrier mixture of the present invention can prevent the floating or outflow of the enzyme or microorganism-immobilized carrier in water, and can secure the fluidity of the carrier in water. Therefore, the fluidized bed bioreactor or the stirring type fermentation is supported. In a tank etc., it can apply suitably for water treatment, for example.
[0040]
The water treatment method of the present invention can be applied to any water treatment system that uses an enzyme or a microorganism-immobilized carrier, with no particular limitation on the content and scale of the treatment. The effect is particularly great in an easy nitrification tank. In addition, the scale of the water treatment system is not particularly limited. In particular, in a relatively small treatment system that treats manure and / or household wastewater of 50 or less people, the surface of the water treatment system will rise and flow out. Since this problem is difficult to solve technically and costly, there is a great advantage in applying the water treatment method of the present invention.
[0041]
【Example】
The present invention will be described more specifically with reference to examples.
[0042]
Production of microorganism-immobilized carrier
Production Example 1
100 parts by weight of a photocurable resin prepolymer obtained by reacting 2,000 g of polyethylene glycol having a molecular weight of about 4,000, 222 g (1 mol) of isophorone diisocyanate and 130 g (1 mol) of 2-hydroxyethyl methacrylate, and benzoin isobutyl ether 2 parts by weight, 100 parts by weight of a 2% aqueous sodium alginate solution, “MB-20” (trade name, manufactured by Toshiba Ballotini, specific gravity 2.5, glass beads having an average particle diameter of 10 to 12 μm), 45 parts by weight, and distilled water 100 When an aqueous liquid composition obtained by thoroughly mixing parts by weight was dropped into a 1 molar calcium chloride aqueous solution from the tip of the syringe at a liquid surface height of 10 cm, a granular material was obtained.
[0043]
This granular material is taken up in a Petri dish having a flat bottom surface, and irradiated with an actinic ray having a wavelength of 300 to 400 nm from the upper and lower surfaces of the Petri dish for 3 minutes. The specific gravity is 1.06, the particle diameter is 4.5 mm, and the sedimentation speed in water is 6. A microorganism-immobilized carrier (A-1) having a thickness of 7 cm / second was obtained.
[0044]
Production Example 2
In Production Example 1, instead of 45 parts by weight of “MB-20”, 7 parts by weight of “Q-Ce1570” (trade name, manufactured by Toshiba Barotini Co., Ltd., specific gravity 0.34, fine hollow glass beads having a particle diameter of 1 to 50 μm) Except for blending, the same operation as in Production Example 1 was performed to obtain a microorganism-immobilized carrier (B-1) having a specific gravity of 1.01, a particle diameter of 4.5 mm, and a sedimentation speed of 3.0 cm / sec in water.
[0045]
Production Example 3
In Production Example 1, as an aqueous composition, 100 parts by weight of a 25% aqueous solution of a photocurable resin obtained by adding 101.1 g (1 mol) of N-methylolacrylamide to 500 g of polyvinyl alcohol having a polymerization degree of 500 was added to benzoin. Except for using an aqueous liquid composition obtained by uniformly mixing 0.5 parts by weight of isobutyl ether and uniformly mixing and dispersing 100 parts by weight of a 3% κ-carrageenan aqueous solution and 65 parts by weight of “MB-20”. The same operation as in Production Example 1 was performed to obtain a microorganism-immobilized carrier (A-2) having a specific gravity of 1.08, a particle size of 3.6 mm, and a sedimentation speed of 5.6 cm / second in water.
[0046]
Production Example 4
In Production Example 3, instead of 65 parts by weight of “MB-20”, 2.5 parts by weight of “Filite300 / 7” (trade name, Nippon Ferrite Co., Ltd., specific gravity 0.7, hollow alumina silica having an average particle size of 75 μm) The same procedure as in Production Example 3 was carried out except that, to obtain a microorganism-immobilized carrier (B-2) having a specific gravity of 1.005, a particle size of 3.6 mm, and a sedimentation speed of 1.7 cm / sec in water.
[0047]
Production Example 5
The same procedure as in Production Example 1 was carried out except that “MB-20” was not blended in Production Example 1, and a microorganism-immobilized carrier having a specific gravity of 1.02, a particle size of 4.4 mm, and a sedimentation speed of 4.4 cm / second in water. (A-3) was obtained.
[0048]
Example 1
Flow of carrier using a mixture of 40 L of microorganism-immobilized carrier (A-1) obtained in Production Example 1 (liter, the same applies hereinafter) and 10 L of microorganism-immobilized carrier (B-1) obtained in Production Example 2 as a carrier. It used for the test.
[0049]
Example 2
A mixture of the microorganism-immobilized carrier (A-2) 25L obtained in Production Example 3 and the microorganism-immobilized carrier (B-2) 25L obtained in Production Example 4 was used as a carrier and subjected to a carrier flow test.
[0050]
Example 3
A mixture of the microorganism-immobilized carrier (A-2) 15L obtained in Production Example 3 and the microorganism-immobilized carrier (B-1) 35L obtained in Production Example 2 was used as a carrier and subjected to a carrier flow test.
[0051]
Example 4
A mixture of 35 L of the microorganism-immobilized carrier (A-3) obtained in Production Example 5 and 15 L of the microorganism-immobilized carrier (B-2) obtained in Production Example 4 was used for the carrier flow test.
[0052]
Comparative Example 1
50 L of the microorganism-immobilized carrier (A-1) obtained in Production Example 1 was used as a carrier and subjected to a carrier flow test.
[0053]
Comparative Example 2
50 L of the microorganism-immobilized carrier (B-1) obtained in Production Example 2 was used as a carrier and subjected to a carrier flow test.
[0054]
Carrier flow test
(1) Evaluation of carrier outflow prevention
A structure in which a carrier fluid tank (capacity 300L) and a carrier separation tank (capacity 100L) are adjacent to each other and are partitioned from the bottom to a height of 10 cm by a partition plate, and both tanks are connected so that water can pass through the bottom. And a test apparatus (see the drawing) in which a diffuser was installed at a position about 20 cm from the bottom and at the bottom. Here, the capacities of the carrier flow tank and the carrier separation tank were the capacities of the respective tanks that were isolated when the partition plate was extended vertically to the bottom.
[0055]
The tank is filled with tap water and the carrier 50L of each of the above examples or comparative examples, and the tap water is always supplied from the carrier flow tank side to the carrier separation tank side at a constant flow rate (about 10 L / min), and from the bottom. Air ventilation (about 80 L / min) was performed from the air diffuser installed at a position of 20 cm, and after 24 hours, the liquid in the upper part of the carrier flow tank was collected, and the apparent volume ratio of the carrier in the collected liquid was measured. From these values, the ability of the carrier to flow out to the separation tank was evaluated. In this test, the case where the apparent volume ratio of the carrier was 5% or more was evaluated as good (◯).
[0056]
(2) Evaluation of carrier fluidity
Using the test apparatus used for evaluating the carrier outflow prevention property, the tank is filled with tap water and the carrier 50L of each of the above examples or comparative examples, and water is not passed from the carrier flow tank side to the carrier separation tank side. Air flow (approximately 80 L / min) from the air diffuser installed at the bottom, and good fluidity (○) that can be visually observed that the carrier deposited within 30 minutes from the start of air aeration is sufficiently loosened did.
[0057]
The evaluation results in the carrier flow test are shown below.
[0058]
[Table 1]

[0059]
【The invention's effect】
The immobilization carrier mixture of the present invention can prevent the microbial immobilization carrier from floating and flowing out in water such as a fluidized bed bioreactor, and can ensure the fluidity of the microbial immobilization carrier in water.
[0060]
In addition, the water treatment system using the microorganism-immobilized carrier mixture of the present invention makes it possible to achieve both the prevention of floating and outflow of the carrier and the securing of sufficient fluidity, and the water treatment system of the present invention particularly supports the carrier by aeration. The effect can be greatly exerted in a nitrification tank where buoyancy and outflow of the slag easily occur. In particular, in a relatively small-scale treatment system for treating manure and / or household wastewater of 50 people or less, the problem of rising and outflow is difficult to solve technically and costly. The advantage of applying a water treatment system is great.
[Brief description of the drawings]
FIG. 1 is a schematic diagram (side sectional view, schematic diagram from the top) showing an outline of a carrier flow test apparatus.
FIG. 2 is a schematic diagram of a carrier flow test apparatus at the time of evaluating the carrier outflow prevention property.
FIG. 3 is a schematic diagram of a carrier flow test apparatus at the time of carrier fluidity evaluation.

Claims (7)

(A) a sedimentation rate in water is 4.2 to 10 cm / sec enzyme immobilization carrier or microorganism immobilization pellets, the sedimentation rate in (B) in water is 0.8 to 3.0 cm / sec, and The enzyme- immobilized carrier or the microorganism-immobilized carrier (A) comprises a mixture of the enzyme- immobilized carrier or the microorganism-immobilized carrier that is 0.4 cm / second or more smaller than the sedimentation rate of the enzyme- immobilized carrier or the microorganism-immobilized carrier (A). (B) and the carrier volume ratio floating in water, characterized in that in (a) / (B) in the range of 20 / 80-90 / 10, outflow enzyme immobilization carrier or microorganism fixed is prevented Carrier mixture. The enzyme- immobilized carrier or microorganism-immobilized carrier (A) has a specific gravity of 2.0 to 4.5 and contains inorganic particles that are insoluble or hardly soluble in water. The mixture according to 1. Claim 1 or 2, wherein the enzyme-immobilized carrier or microorganism-immobilized carrier (B) is one which contains an inorganic substance infinitesimal hollow beads having a specific gravity within the range of 0.2 to 0.8 Mixture of. The enzyme- immobilized carrier or the microorganism-immobilized carrier (A) is (a) a hydrophilic photocurable resin having at least two ethylenically unsaturated bonds in one molecule, (b) a photopolymerization initiator, (c) water-soluble polymeric polysaccharide capable of gelation upon contact with an alkali metal ion or polyvalent metal ion,及beauty (d) to and water has a specific gravity of 2.0 to 4.5 of the insoluble or sparingly soluble An aqueous liquid composition comprising an inorganic powder granule is dropped into an aqueous medium containing alkali metal ions or polyvalent metal ions to gel the composition into granules, and then the resulting granular gel is treated with actinic rays. The mixture according to any one of claims 1 to 3, wherein the mixture is an enzyme-immobilized carrier or a microorganism-immobilized carrier obtained by irradiating a photocurable resin in the granular gel by irradiation. . The enzyme- immobilized carrier or the microorganism-immobilized carrier (B) is (a) a hydrophilic photocurable resin having at least two ethylenically unsaturated bonds in one molecule, (b) a photopolymerization initiator, (c) inorganic matter infinitesimal hollow beads having a specific gravity within the range of alkali metal ions or water-soluble polymeric polysaccharide capable of gelation upon contact with a polyvalent metal ion,及beauty (e) 0.2 to 0.8 An aqueous liquid composition comprising the above is dropped into an aqueous medium containing alkali metal ions or polyvalent metal ions to gel the composition, and then the resulting granular gel is irradiated with actinic rays. The mixture according to any one of 1 to 4, which is an enzyme- immobilized carrier or a microorganism-immobilized carrier obtained by curing the photocurable resin in the granular gel. (A) a sedimentation rate in water is 4.2 to 10 cm / sec enzyme immobilization carrier or microorganism immobilization pellets, the sedimentation rate in (B) in water is 0.8 to 3.0 cm / sec, and The enzyme- immobilized carrier or the microorganism-immobilized carrier (A) comprises a mixture of the enzyme- immobilized carrier or the microorganism-immobilized carrier that is 0.4 cm / second or more smaller than the sedimentation rate of the enzyme- immobilized carrier or the microorganism-immobilized carrier (A). An enzyme- immobilized carrier or microorganism characterized in that a carrier mixture having a carrier volume ratio with (B) in the range of 20/80 to 90/10 in (A) / (B) is used as a carrier for water treatment. Water treatment method using immobilized carrier.   The water treatment method according to claim 6, wherein the carrier mixture is used in a nitrification tank with aeration.

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