JPH08224076A - Bioreactor - Google Patents

Abstract

PURPOSE: To provide a bioreactor which can remove or increase specific components in the solution to be treated without addition of an energy substance. CONSTITUTION: In this bioreactor, an,ammonium oxidizing bacterium or denitrifying bacterium is immobilized on a synthetic resin carrier such as a photosetting resin and the resin is formed in tubes or films and an liquid or gaseous energy substance such as ethanol or a hydrogen gas is allowed to flow on one face of the bacterium-immobilized carrier, while the solution to be treated is brought into contact with the other face to increase or remove a specific component in the solution. 1 is the experimental tank, 2 is a water bath for keeping warm the air stone and the experimental tank, 3 is a culture medium (solution to be treated), 4 is an air pump, 5 is an air stone, 6 is a pipe and 8 is a stirring blade. The ethanol solution is circulated through the pipe 14 using the pump 13 to remove the nitrogen in the culture medium 3.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a bioreactor for efficiently removing a specific component in a liquid to be treated, for example, a nitrogen component such as ammonia contained in water such as waste water by microorganisms.

[0002]

2. Description of the Related Art Nitrogen compounds such as ammonia flowing into lakes and closed seas are one of the main causative substances of eutrophication. Therefore, the drainage standard for nitrogen is strengthened,
At present, discharge into rivers and sea areas is under severe control.

At present, a biological denitrification method is widely used as a method for removing nitrogen compounds in waste water. However, in the existing wastewater treatment equipment using the biological denitrification method, an aerobic tank (nitrification reaction) and an anaerobic tank (denitrification reaction) are used.
Therefore, there is a problem that the device becomes large and complicated. Also, it is necessary to add organic substances such as alcohol to the denitrification tank as an energy source for the denitrification reaction.
It is necessary to install a re-aeration tank to remove the alcohol remaining in the treated water. In addition, pH adjustment is required,
There are also problems such as low utilization efficiency of the added alcohol and high operating costs.

[0004]

The present invention relates to a bioreactor capable of removing or increasing a specific component in a liquid to be treated by using a microorganism. For example, there are problems in a conventional nitrogen treatment device. It is intended to provide a new nitrogen-removing bioreactor that can efficiently perform nitrification and denitrification reaction in one reaction tank, and can efficiently supply energy source substances to denitrifying bacteria and the like. Is.

[0005]

Means for Solving the Problems As a result of various researches, the present inventor has made a film of an immobilized carrier in which an ammonia-oxidizing bacterium and / or a denitrifying bacterium is embedded in a carrier such as a synthetic polymer or a natural polymer. It was found that nitrogen can be removed efficiently by molding it into a sheet, tube, etc., and contacting the liquid to be treated on one surface of this carrier for immobilizing bacteria and contacting the energy source substance of the bacteria on the other surface, and also for other microorganisms. The present invention has been completed by finding out that it can be similarly applied. Therefore, the present invention provides an immobilization carrier having one or more microorganisms immobilized on a synthetic or natural polymer carrier such as a photocurable resin or agarose, which is effective for removing a target component in a liquid to be treated. The present invention relates to a bioreactor, wherein one surface is brought into contact with a liquid to be treated and the other surface is brought into contact with an energy source substance of the microorganism.

As a specific example of the present invention, it is effective for removing nitrogen or nitrogen components in a liquid to be treated such as ammonia-oxidizing bacteria and denitrifying bacteria on a synthetic or natural polymer gel carrier such as photocurable resin and agarose. Bioreactor for removing nitrogen, wherein one surface of an immobilization carrier on which one or more kinds of various microorganisms are immobilized is brought into contact with a liquid to be treated and the other surface is brought into contact with an energy source substance of the microorganism. Can be mentioned. In the present invention, the microorganisms effective for removing nitrogen or nitrogen components in the liquid to be treated are preferably ammonia-oxidizing bacteria and / or denitrifying bacteria, and the carrier may be further immobilized with nitrite-oxidizing bacteria. Good.

In the present invention, as the ammonia-oxidizing bacteria, the denitrifying bacteria, and the nitrite-oxidizing bacteria, those conventionally known in the field of this kind can be used. More specifically, for example, as the ammonia-oxidizing bacteria, Nitrosomonas europaea IFO-14298, Nitrosomonas europaea, N.marina , Nitrosococcus oceanus , N.mobilis, Nitrosococcus sp.DA-001 (FERM P-12904) , Nitrosospira briensis, Nitrosolobus multiformis, Nitrosovibrio tenuis, deificative fungus, and denitrifying fungi -6892 *, Paracoccus denitrificans *, Alcaligenes eutrophus *, A.faecalis Alcaligenes sp. Ab-A-1, Ab-A-2, GA-2-1 ( FERMP-138
62, P-13860, P-13861 ) Pseudomonas denitrificans, Thiosphaera pantotropha, Thiobacillus denitrificans **, and nitrite-oxidizing bacteria include Nitrobacter winogradskyi N.hamburgensis Nitrospina gracilis Nitrococcus mobilis Nitrospira marina . The underlined strains are strains applicable only to the treatment of seawater, and the other strains are strains applicable to the treatment of fresh water. N. europaea and N. winogradskyi are available in freshwater and seawater. The strain with the FERM number has been deposited by the applicant with the Institute for Microbial Technology and the deposit number is shown.
The bacteria marked with * are strains that can use hydrogen as an energy source instead of organic substances such as ethanol,
Bacteria marked with ** are strains that can use only sulfur as an energy source and can denitrify using sulfur compounds such as thiosulfate.

In the present invention, the above-mentioned strains may be immobilized alone or in combination with the same or different strains on a single carrier. When considering a microbial reaction system that also involves nitrite-oxidizing bacteria, like a general denitrification method, it is possible to use a mixed microbial system. It can also be fixed to. The present invention, in addition to the above-mentioned bacteria for removing nitrogen, as a strain capable of removing or increasing specific components in the liquid to be treated, microorganisms such as Achromobacter in activated sludge and Alcaligenes, and drainage. Microorganisms for removing phosphorus, iron bacteria and the like can be used as they are, or microorganisms that promote the reproduction of these microorganisms can be used.

As a carrier for immobilizing bacteria, polymer gels used for immobilizing microorganisms and enzymes can be used. Specifically, collagen, fibrin, albumin, casein, cellulose fiber, cellulose triacetate, agar, calcium alginate, carrageenan, natural polymers such as agarose, polyacrylamide, poly-2-hydroxyethyl methacrylic acid, polyvinyl chloride, Synthetic polymers such as γ-methylpolyglutamic acid, polystyrene, polyvinylpyrrolidone, polydimethylacrylamide, polyurethane, photocurable resins (polyvinyl alcohol derivatives, polyethylene glycol derivatives, polypropylene glycol derivatives, polybutadiene derivatives, etc.), or composites thereof Is mentioned. Among these carriers, a gel having a low strength such as a natural polymer may be used with an appropriate support or sandwiched between porous membranes. The shape of the immobilization carrier in the bioreactor may be a tube shape, a plate shape, a film shape, or the like, and may be a molded body having a specific shape.

The present invention is particularly suitable for removing nitrogen, which is formed into a tubular shape by immobilizing microorganisms such as ammonia-oxidizing bacteria and / or denitrifying bacteria on a polymer gel carrier having high strength such as photocurable resin. Bioreactors are preferred.
The hollow portion of the bacterium-immobilized carrier thus formed in a tube shape is allowed to circulate a liquid such as methanol or ethanol or a gas such as hydrogen gas so that a substance serving as an energy source for the immobilized bacterium can be replenished. It was done. The tube of the immobilization carrier does not have to be one, and the tubes of the immobilization carrier carrying the ammonia-oxidizing bacteria and the tubes of the carrier immobilizing the denitrifying bacteria may be alternately arranged in the treatment tank, Further, a plurality of carriers on which both bacteria are immobilized may be arranged. The tube need not be straight, but may be curved or spiral.

In the above, the carrier itself is formed into a tubular shape. However, the present invention is further characterized in that the ammonia-oxidizing bacterium and / or the deoxidizing agent is removed from the carrier on the open surface of a container such as a gutter-shaped container whose one surface is open. It is possible to form a layer of an immobilizing carrier on which immobilizing bacteria such as nitrifying bacteria and to allow a liquid or gas such as an ethanol solution or hydrogen gas to flow in the space on the back surface of the layer of the immobilizing carrier. In this case, the container is not limited to a gutter-shaped one, and the immobilization carrier is molded into a shape in which the tube is divided into two along its axis, and one surface is covered with a glass plate, a plastic plate, or a plastic film, The inside of the container is divided by a large number of plate-shaped immobilization carriers, an ethanol solution is passed between the immobilization carriers and the liquid to be treated is passed between the immobilization carriers. It may be formed in various shapes such as. It is preferable that the surface of the immobilization carrier is larger and is in contact with the liquid to be treated.

The thickness of the immobilization carrier is not particularly limited, and can be arbitrarily selected within the range where the denitrification reaction is efficiently performed according to the properties of the liquid to be treated and the required strength. Usually, a thickness of about 0.5 to 10 mm, especially about 1 mm is preferable. The amount of bacteria to be immobilized on the carrier and the ratio of ammonia-oxidizing bacteria to denitrifying bacteria are arbitrarily set depending on the liquid to be treated such as wastewater to be treated. As the energy source material for the immobilization carrier, an organic solution such as glucose or an effluent containing an organic matter can be used in addition to the above alcohol solution such as methanol and ethanol, hydrogen gas and the like. Alternatively, a sulfur or sulfur compound solution can be used as an energy source using autotrophic sulfur-oxidizing bacteria. The energy source substance may be diluted with an appropriate medium according to the property of the immobilization carrier before use. When supplying the energy source substance, these liquids or gases may be subjected to temperature control such as heating or cooling, if necessary. The energy source substance may be supplied from the outside of the system by a circulation system, or by a batch system in which the required amount is filled in the closed space on one surface of the immobilization carrier.

[0013]

EXAMPLES The present invention will be described below with reference to experimental examples and examples, but the present invention is not limited to these examples.

Experimental Example 1) Test strain and its culture Nitrosomonas europ as nitrifying bacteria (ammonium oxidizing bacteria)
aea IFO-14298, Paracoccus denitrifica as a denitrifying bacterium
ns JCM-6892 was used. For culture, N. europaea is IFO Me
dium List No.240, P.denitrificans JCM Medium List
A liquid medium based on No. 22 (Nutrient agar No. 2) was used. The composition of the medium is shown in Table 1. After shaking (110 rpm) culture at 30 ° C, the cells were harvested by centrifugation and phosphate buffer (9 g / l Na ₂ HPO ₄ · 12H ₂ O, 1.5 g / l KH ₂ PO ₄ , pH).
Washed 3 times with 7.5). The washed cells were 8 mg dry wt./ml for N. europaea and 33 mg dry wt./ for P. denitrificans.
The suspension was suspended in phosphate buffer so that the volume of each suspension became 1 ml.

[0015]

[Table 1] * 1: Phenol Red (phenol red) was added to IFO medium No. 240 as a pH indicator, and the pH was adjusted by appropriately adding Na ₂ CO ₃ instead of CaCO ₃ . * 2: Agar was removed from JCM medium No. 22 and used as a liquid medium.

2) Immobilization method 9 ml of the photocurable resin PVA-SbQ (SPP-H-13, manufactured by Toyo Gosei Co., Ltd.) was added to the above-mentioned N. europaea bacterial suspension 1
2 ml of P. denitrificans suspension was mixed and immobilized. When immobilizing N. europaea alone, P. denitrif
Instead of the icans bacterial suspension, 2 ml of phosphate buffer was added. The mixed solution of the bacterial cells and the resin was used as a mold using a glass dish containing a plastic petri dish and a glass rod, and was irradiated with light under a metal halogen lamp for 1 hour to form a film-shaped immobilized carrier (diameter 5 cm, thickness 5 mm). And a tubular fixed carrier (outer diameter 12 mm, inner diameter 5 mm, length 125 mm).
In order to supply the ethanol solution to the inside of the tubular immobilization carrier, a silicone tube having an outer diameter of 4 mm and an inner diameter of 2 mm was adhered to the front and rear of the tubular immobilization carrier using a photocurable resin.

3) Experiment 1: Denitrification Experiment with Membrane-Immobilized Carrier The membrane-immobilized carrier prepared by embedding N. europaea alone and N. europaea and P. denitrificans prepared at the same time in the above Example were simultaneously encapsulated. The nitrification and denitrification rates were measured for the embedded membranous immobilized carrier. A schematic diagram of the experimental apparatus is shown in FIG. In the figure, 1 is an experimental tank, 2 is a water bath (water bath) for keeping the experimental tank 1 warm, and 3 is a medium. The test film-shaped immobilization carrier 10 was formed in a fixture 9 such as a fixing frame or a petri dish, and immersed in the medium 3. The medium 3 is aerated by ejecting air from an air stone 5 by an air pump 4 and agitated by a stirrer 7. 6 is a pipe, and 8 is a stirring blade. The experiment was performed under the condition of 30 ° C., and aeration (100 ml / min) and stirring by the stirrer 7 (300 rpm) were performed at the same time. The experimental medium 3 was 0.2 gN / 1 (NH ₄ ) ₂ SO ₄ , 0.2 g / l Mg in the above-mentioned phosphate buffer.
SO ₄ · 7H ₂ O, trace elements (trace element) solution (ZnSO ₄ 10
0mg / l, MnCl ₂ 30mg / l, H ₃ BO ₃ 300mg / l, CoCl ₂・ 6H ₂ O 200
mg / l, CuCl ₂・ 2H ₂ O 10mg / 1, NiCl ₂・ 6H ₂ O 20mg / l, Na ₂ MoO ₄
・ 2H ₂ O 30 mg / l) 1 ml / l was added to the 200 ml solution,
Ammonia, nitrous acid, and nitric acid concentrations in the medium were measured over time. In addition, ethanol was added for denitrification to the immobilization carrier in which N. europaea and P. denitrificans were embedded at the same time. The method of adding ethanol was 99.5% in the experimental medium.
0.5 ml of ethanol (final concentration 0.25%) was added directly, and 9 ml of ethanol was added to 0.125 ml (4 ml) every 24 hours in 5 ml of phosphate buffer injected to the back side of the immobilization carrier (gap between the dish). The total daily addition amount of 0.5 ml) was added in two ways.

4) Experiment 2: Denitrification experiment using tubular immobilization carrier The nitrification and denitrification rates of the tubular immobilization carrier in which N. europaea and P. denitrificans were simultaneously embedded were measured. A schematic diagram of the experimental apparatus is shown in FIG. In FIG. 2, 11 is a tubular immobilization carrier, 11a is a silicone tube adhered to both ends of the tubular immobilization carrier 11, 12 is an ethanol solution, 13 is a circulation pump, 14 is a pipe, and others are described in FIG. The same reference numerals are used for the same items. The experiment was performed under the condition of 30 ° C, and the aeration and the stirrer 7 were used.
The stirring was carried out in the same manner as in the case of the film-shaped immobilized carrier. Experimental medium 3 was 0.1 gN / 1 in the above-mentioned phosphate buffer.
_{(NH 4) 2 SO 4,} 0.2 g / l MgSO 4 · 7H 2 O, trace elements (trace el
ement) Solution 200 ml solution containing 1 ml / l was used to measure the concentration of ammonia, nitrous acid, nitric acid and TOC in the medium over time. In the inside of the tubular immobilization carrier 11, 9
The pump 13 was set (5 ml / h) so that 10 ml of phosphate buffer solution (final concentration of ethanol 0.5% and 1.0%) supplemented with 0.05 ml and 0.1 ml of 9.5% ethanol was circulated. In addition, the generated gas was collected and analyzed.

5) Analytical method The concentrations of ammonia and nitrite in the medium solution were measured by indophenol blue absorptiometry and naphthylamine absorptiometry. Nitric acid concentration is ion chromatograph analyzer (IC-500P, manufactured by Yokogawa Electric), TOC concentration is combustion-
An infrared type total organic carbon analyzer (TOC-500, manufactured by Shimadzu Corporation), and the composition of the generated gas was analyzed by a gas chromatoanalyzer with a PID detector (G-3000, manufactured by Hitachi Ltd.).

Results 1) Denitrification by a membrane-like immobilized carrier In order to confirm that nitrification and denitrification reaction occur simultaneously, N.
Membrane-shaped immobilization carrier embedded with europaea, or N. europaea
The nitrification and denitrification rates of a membranous co-immobilized carrier in which P. and P. denitrificans were simultaneously embedded were measured. In the immobilized carrier in which N. europaea was embedded, the ammonia concentration in the experimental medium 3 decreased with time and the nitrite concentration increased (Fig. 3A). On the other hand, in the immobilization carrier in which N. europaea and P. denitrificans were embedded at the same time, the ammonia concentration in the experimental medium decreased with time, but the nitrite concentration slightly increased from the 2nd day, but the experiment was completed. Sometimes decreased (Figure 3B). This tendency was the same even when the ethanol supply method was changed (Fig. 3C). Nitrate was not detected in any of the experimental media. In addition, the nitrification rate (NH ₄ → NO ₂ ) and denitrification rate (NO ₂ → N ₂ ) calculated from the concentration of ammonia and nitrite in the experimental medium after 13.5 hours from the start of the experiment on each immobilized carrier are shown in the table. 2 shows. The nitrification rate was higher in the immobilized carrier in which N. europaea and P. denitrificans were simultaneously embedded than in the immobilized carrier in which N. europaea was embedded alone. Also N. europaea
In the immobilization carrier in which P. and P. denitrificans were embedded at the same time, no difference was observed in the nitrification rate and the denitrification rate when ethanol was added to the experimental medium or injected between the immobilization carrier and the dish.

[0021]

[Table 2] The nitrification rate and denitrification rate were calculated from the concentration of inorganic nitrogen in the medium after 13.5 hours. * 1: 0.25% (V / V) ethanol was directly added to the medium. * 2: A 2.5% (V / V) ethanol solution was added to the side opposite to the medium.

2) Denitrification by a tubular immobilization carrier In a tubular immobilization carrier in which N. europaea and P. denitrificans were embedded at the same time, a denitrification experiment was conducted by circulating an ethanol solution in the tube. As in the case of the membranous immobilized carrier, the concentration of ammonia in the experimental medium decreased with time. The nitrite concentration increased slightly after the second day, but disappeared with ammonia at the end of the experiment (Fig. 4). Nitrate was not detected in the experimental medium. The TOC concentration in the experimental medium increased from the beginning of the experiment to 58 mg-C / l at the end of the experiment. However, when the ethanol concentration was lowered to 0.5%, the activity did not change, and the TOC concentration was 40 mg · C / l at the start of the experiment, but it did not rise further (Fig. 5). Gas generation due to the denitrification reaction was observed only in the tube. The collected gas was nitrogen, and no intermediate product of denitrification such as nitrous oxide was detected.

As can be seen from the above experimental results, N. euro
It was shown that by immobilizing paea and P. denitrificans at the same time, nitrification and denitrification reactions occur at the same time, and the nitrification activity is improved as compared with the case of N. europaea alone (Fig. 3, Table 2). It is known that P. denitrificans has no denitrifying activity under aerobic conditions. However,
The reason why the nitrification and the denitrification reaction occur simultaneously in the bioreactor of the present invention is that the supply of oxygen into the resin as a carrier is limited, and N. europaea consumes the oxygen, so that the anaerobic reaction required for the denitrification reaction is It is considered that the target site was created. In addition, the improvement of nitrification activity by simultaneous immobilization is described in N.
P. co-immobilized with nitrous acid, a reaction product of europaea.
It is considered that this is because the denitrification by denitrificans promptly removes it.

By the above experiment, the simultaneous immobilization of the ammonia-oxidizing bacteria and the denitrifying bacteria as well as the method of supplying ethanol to the denitrifying bacteria was investigated, and ethanol was supplied from the surface opposite to the surface of the immobilized carrier in contact with the experimental medium. It is also possible (Table 2). Further, by making the immobilization carrier into a tube shape, denitrification became possible by continuous supply of ethanol (Fig. 4). The ethanol supply method of the present invention is capable of directly supplying a high concentration of ethanol to the denitrifying bacteria in the immobilized carrier as compared with the conventional method of directly adding it to treated water, and the ethanol is consumed in the carrier, and thus in the experimental medium. Since it does not leak out, it is possible to omit the step of removing ethanol remaining in the treated water, which has been conventionally performed.

The amount of ethanol used in the above experiment corresponds to the case where ethanol is directly added to the waste water at a concentration of 0.025%, and low concentration ethanol can be efficiently used. Further, the TOC concentration in the experimental medium increased at the start of the experiment, but did not increase further (Fig. 5). The reason for this is considered to be that, immediately after immobilization, the consumption of ethanol was low until the denitrifying bacteria in the carrier consumed the organic substances brought in, and the ethanol leaked into the treated water. Therefore, T
The accumulation of OC can be prevented by examining the ethanol concentration and stabilizing the immobilization carrier.

FIG. 6 is a graph showing the results of another experimental example of the present invention, which is an example in which hydrogen gas is used as the energy source instead of ethanol. FIG. 6A shows the results of examining removal of nitrate nitrogen when a tubular immobilization carrier in which only denitrifying bacteria were immobilized in the above experiment was used, and nitrogen gas was supplied in the tube of the carrier instead of the ethanol solution. , In this case, nitric acid decreases due to the organic matter remaining in the cells during immobilization, but it does not decrease thereafter. On the other hand, when hydrogen gas was supplied instead of nitrogen gas as shown in FIG. 6B, the amount of nitrate nitrogen decreased with the passage of time. When hydrogen is used as an energy source for bacterial cells, unlike when using organic substances such as alcohol,
Since it has little effect on the human body, it can be used for treatment of tap water used as drinking water or treatment of groundwater. Further, since hydrogen gas does not leak out and does not need to be dissolved in water, it is effective in terms of safety and cost.

As can be seen from the above results, according to the bioreactor of the present invention, any energy source substance such as hydrogen gas and sulfur compounds can be used as the energy source of the bacterial cells in addition to alcohol. When hydrogen is used as the energy source substance, a hydrogen gas permeable plastic tube or the like is used, and a method such as forming an immobilization carrier layer on the outer peripheral surface of the hydrogen gas unnecessarily removes the gas from the treatment system. Means such as preventing leakage may be used. From these results, the tubular immobilization carrier of the present invention is extremely effective in reducing the size and efficiency of the system because it reduces the treatment cost and eliminates the need for integrating the nitrification tank and denitrification tank and the re-aeration tank. is there.

In the above experimental example, a straight tubular immobilization carrier was shown, but some of the application examples of the bioreactor of the present invention are shown below. Example 1 In FIG. 7, a large number of tube-shaped bacterium-immobilized carriers 21 are held by a support frame 22, and a passage in the tube-shaped carrier 21 is provided.
The energy source substance A is supplied to 21a. The structure is similar to that of a boiler or the like, and the energy source substance A is used instead of the heating medium of the boiler and can be used as a liquid to be treated outside the tube. In this case, the liquid to be treated may be flown into the tube and the outside of the tube may be used as the energy source substance A. Instead of the tubular immobilization carrier, a hollow plate-shaped carrier may be similarly fixed to the support frame and used. Example 2 FIG. 8 is an example in which the tubular immobilization carrier 21 has a spiral shape. It can be used in the same manner as in Example 1.

Example 3 FIG. 9 shows an example in which a large number of tubular immobilization carriers 21 having one end closed are held by a support frame 22. Example 4 In FIG. 10, a large number of flat plate-shaped immobilization carriers 20 are arranged in parallel at appropriate intervals, and the energy source substance A and the liquid to be treated B are alternately passed between the flat plate-shaped carriers 20. Here is an example. In this case, the intervals between the carriers 20 do not have to be all the same, and may be set arbitrarily such that the passage of the energy source substance A is widened and the liquid to be treated B side is narrowed.

Embodiment 5 FIG. 11 shows that a pipe 23 is provided inside a pipe 23 such as a waste liquid treatment pipe.
Flat plate-shaped immobilization carrier 20 so as to be divided into two diametrical directions
In this example, the energy source substance A flows on one side of the carrier 20 and the liquid B to be treated flows on the other side. Also in the case of this example, as in the case of the fourth embodiment, the passage on one side may be widened and the other side may be narrowed.

[0031]

EFFECTS OF THE INVENTION The bioreactor of the present invention comprises a balance of the numbers of ammonia-oxidizing bacteria and denitrifying bacteria in the immobilization carrier, a ratio of aerobic and anaerobic parts in the immobilization carrier, concentration of bacteria and immobilization carrier layer. By appropriately selecting and setting the thickness, for example, adjustment of the wall thickness of the tube in the case of a tubular immobilization carrier, wastewater and the like can be treated more efficiently. When the bioreactor of the present invention is used as a continuous treatment tank, the treatment conditions such as the residence time in the treatment tank, the concentration of the circulating energy source substance, and the aeration amount in the treatment tank are appropriately selected as in the above. By setting the above, wastewater and the like can be treated more efficiently. In addition, a thin resin layer that does not inhibit the activity of bacteria is formed on at least the surface of the immobilization carrier that is in contact with the liquid to be treated, such as drainage, for the purpose of preventing leakage of bacteria from the immobilization carrier and providing strength. You may.

When the immobilization carrier is formed into a film shape, a sheet shape or a tube shape, in addition to the immobilization carrier alone, a suitable metal or plastic frame, for example, a lattice-shaped or honeycomb-shaped frame is used. By forming it in the gap, it can be made to have a predetermined size. The present invention has been described mainly for removing nitrogen in the liquid to be treated, but by using a similar bioreactor using various microorganisms, the components in the liquid to be treated can be removed without being affected by the energy source substance. In addition, by using a microorganism that releases a substance necessary for the growth of a specific microorganism in the liquid to be treated, it is possible to grow a specific microorganism in the liquid to be treated or increase a specific component. it can.

[Brief description of drawings]

FIG. 1 is a schematic view of an experimental device for a membranous immobilized carrier.

FIG. 2 is a schematic view of an experimental device for a tubular immobilization carrier.

FIG. 3 is a graph showing the effect of treating the membrane-shaped immobilized carrier with ammonia and nitrous acid.

FIG. 4 is a graph showing the effect of treating the tube-shaped immobilized carrier with ammonia and nitrous acid.

FIG. 5 is a graph showing TOC concentration in an experimental medium.

FIG. 6 is a graph showing the effect of removing nitrate nitrogen of a tubular immobilization carrier when hydrogen gas is used as an energy source.

FIG. 7 is a side view showing an example of the bioreactor of the present invention.

FIG. 8 is a side view showing an example of use of a tubular immobilization carrier.

FIG. 9 is a side view showing another example of use of the tubular immobilization carrier.

FIG. 10 is a perspective view showing an example of use of a flat immobilization carrier.

FIG. 11 is a perspective view showing another usage example of the flat plate-shaped immobilization carrier.

[Explanation of symbols]

 1 Experimental Tank 2 Water Bath 3 Experimental Medium 4 Air Pump 5 Air Stone 7 Stirrer 8 Stirring Blade 10 Membrane Immobilized Carrier 11 Tube Immobilized Carrier 11a Silicone Tube 12 Ethanol Solution 13 Circulation Pump 20 Flat Plate Immobilized Carrier 21 Tube Immobilized Carrier 22 support frame 23 tubular body

Claims (13)

[Claims] 1. A surface of an immobilizing carrier in which one or more kinds of microorganisms effective for removing a target component in a liquid to be treated are immobilized on a carrier such as a synthetic polymer or a natural polymer. A bioreactor characterized in that the treatment liquid is brought into contact with the other surface of the microorganism as an energy source substance. 2. As a microorganism effective for removing a target component of a carrier such as a synthetic polymer or a natural polymer, it is effective for removing nitrogen or nitrogen component in a liquid to be treated such as ammonia-oxidizing bacteria and denitrifying bacteria. One or more kinds of microorganisms are immobilized, and the liquid to be treated is brought into contact with one surface of the immobilized carrier and the energy source substance of the microorganism is brought into contact with the other surface to remove nitrogen or nitrogen components. The bioreactor according to claim 1, which is characterized. 3. A liquid to be treated is brought into contact with one surface of an immobilization carrier on which ammonia-oxidizing bacteria and / or denitrifying bacteria are immobilized as microorganisms effective for removing nitrogen or nitrogen components, and an energy source substance for bacterial cells is attached to the other surface. The bioreactor according to claim 2, wherein the bioreactor is brought into contact with the bioreactor. 4. The bioreactor according to claim 2, wherein nitrite-oxidizing bacteria are further immobilized. 5. The ammonia-oxidizing bacterium is Nitrosomonas europ.
aea IFO-14298, denitrifying bacteria Paracoccus denitrificans J
The bioreactor according to claim 2, which is CM-6892. 6. The carrier is a natural polymer such as collagen, fibrin, albumin, casein, cellulose fiber, agar or agarose, polyacrylamide, poly-2.
-Hydroxyethyl methacrylic acid, polyvinyl chloride, polystyrene, polyurethane, a synthetic polymer of a photocurable resin (polyvinyl alcohol derivative, polyethylene glycol derivative, etc.), or a complex thereof. The bioreactor according to any one of claims 1. 7. The bioreactor according to claim 1, wherein the immobilized carrier has a tube shape, a plate shape, or a film shape. 8. The liquid or gaseous energy source substance such as ethanol or hydrogen gas is allowed to flow through the hollow portion of the tube-shaped bacterium-immobilized carrier. Bioreactor for nitrogen removal. 9. A container, such as a box or gutter, whose one surface is open, has a carrier such as a synthetic polymer or a natural polymer on which the microorganisms effective for removing the target component in the liquid to be treated are provided. Forming a layer of an immobilization carrier on which one or more types are immobilized,
A bioreactor characterized in that a liquid or gaseous energy source substance such as ethanol or hydrogen gas is allowed to flow in the space inside the container on the back surface of the layer of the immobilized carrier. 10. The inside of a body such as a box or a cylinder,
Ammonia-oxidizing bacteria on a carrier such as synthetic polymer, natural polymer,
A layer of an immobilizing carrier on which one or more kinds of microorganisms effective for removing a specific component in a liquid to be treated such as denitrifying bacteria is immobilized is divided into two or two or more layers of the immobilizing carrier. A bioreactor characterized in that a liquid to be treated is circulated on one side and an energy source substance of bacterial cells is circulated on the other side. 11. A microorganism which is effective for removing a target component in a liquid to be treated on a carrier such as a synthetic polymer or a natural polymer.
A method for treating a specific component in a liquid to be treated, which comprises immobilizing one or more species, and contacting the liquid to be treated on one surface of the immobilized carrier and bringing the energy source substance of the microorganism into contact with the other surface. 12. As a microorganism effective for removing a target component in a carrier such as a synthetic polymer or a natural polymer, it is effective for removing nitrogen or nitrogen component in a liquid to be treated such as ammonia oxidizing bacteria and denitrifying bacteria. Immobilize one or more microorganisms,
12. The treatment method according to claim 11, wherein the liquid to be treated is brought into contact with one surface of the immobilized carrier and the energy source substance of the microorganism is brought into contact with the other surface thereof to remove nitrogen in the liquid to be treated. 13. The treatment method according to claim 11, wherein the energy source substance of the microorganism that comes into contact with the other surface of the immobilization carrier is heated or cooled to adjust the temperature to a desired temperature and brought into contact with the immobilized carrier.