JP2019169282A - Microorganism power generation device using disinfecting agent and method for operating microorganism power generation device using disinfecting agent - Google Patents

Abstract

To provide a method for operating a microorganism power generation device, maintaining power generation high over the long term by suppressing the growth of methanogens in an anode chamber.SOLUTION: A microorganism power generation device includes: an anode chamber 4 including an anode 6 and holding a liquid containing microorganism and electron donors; and a cathode chamber 3 separated from the anode chamber 4 with an ion permeable non-conductive membrane 2 interposed therebetween. Organic matter-containing raw water is supplied in the anode chamber 4 and a fluid containing electron donors is supplied in the cathode chamber 3 so that power is generated. In the microorganism power generation device, disinfecting agents are intermittently added into the anode chamber 4, and the inside of the anode chamber 4 is intermittently aerated by inert gas from an aeration pipe 17.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power generation apparatus that utilizes a metabolic reaction of a microorganism and a method for operating the microorganism power generation apparatus. In particular, the present invention relates to a microbial power generation apparatus that extracts, as electric energy, a reducing power obtained when an organic substance is oxidatively decomposed into microorganisms, and a method for operating the microbial power generation apparatus.

  As power generation devices using microorganisms, Patent Documents 1 and 2 describe devices in which a cathode chamber and an anode chamber are partitioned by an electrolyte membrane.

  Patent Document 1 describes that by adjusting the pH in the anode chamber to 7 to 9, it is possible to prevent the pH from being lowered due to the generation of carbon dioxide gas accompanying the microbial reaction in the anode chamber and to increase the power generation efficiency. ing.

JP 2009-152097 A JP 2000-133326 A

  When the microorganism power generation device is operated for a long period of time, the power generation microorganisms grow on the electrode surface, but if the microorganisms become excessively attached to the electrode surface, the contact efficiency with the substrate and the conductivity of the electrode surface decrease, and the power generation amount is reduced. Decrease. In severe cases, there was a problem that the anode chamber was blocked and the substrate could not be supplied.

  An object of the present invention is to provide a microbial power generation apparatus and a microbial power generation method capable of suppressing excessive adhesion of microorganisms in an anode chamber and stably obtaining a high power generation amount for a long period of time.

  The microbial power generation device of the present invention has an anode chamber having an anode and holding a liquid containing a microorganism and an electron donor, and a cathode chamber separated from the anode chamber by a porous non-conductive film. In the microbial power generation apparatus for generating power by supplying organic substance-containing raw water to the anode chamber and supplying a fluid containing an electron acceptor to the cathode chamber, a sterilizing agent supplying means for supplying the sterilizing agent to the anode chamber is provided. It is characterized by that.

  In one aspect of the invention, the bactericidal agent is hydrogen peroxide, hypochlorous acid or hypochlorite.

  In one aspect of the present invention, there is provided means for supplying an inert gas to the anode chamber.

  An operation method of a microbial power generation device of the present invention includes an anode chamber having an anode and holding a liquid containing a microorganism and an electron donor, and a cathode chamber separated from the anode chamber via a porous non-conductive film. In a method for operating a microbial power generation apparatus that supplies raw material-containing raw water to the anode chamber and supplies a fluid containing an electron acceptor to the cathode chamber to generate electric power, a disinfectant is intermittently provided in the anode chamber. It is characterized by supplying.

  In one embodiment of the present invention, the sterilizing agent is supplied to the anode chamber at a frequency of once every 2 hours to 30 times for 1 minute to 1 hour.

  In one embodiment of the present invention, an inert gas is supplied continuously or intermittently into the anode chamber.

  In the present invention, the bactericide is preferably supplied intermittently to the anode chamber. Thereby, excessive adhesion of the power generation microorganisms to the anode surface is suppressed, and a high power generation amount can be stably maintained. In addition, in the anode chamber under anaerobic conditions, methane-producing bacteria may grow in addition to power-generating bacteria, which may reduce power generation efficiency. Bacterial growth is further suppressed, and the power generation efficiency can be kept high.

It is a cross-sectional schematic diagram of the microbial power generation device which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram of the microbial power generation device which concerns on one Embodiment of this invention.

  Hereinafter, the present invention will be described in more detail.

  FIG. 1 is a schematic cross-sectional view showing a schematic configuration of a microbial power generation apparatus according to an embodiment of the present invention.

  The tank body 1 is partitioned into a cathode chamber 3 and an anode chamber 4 by a partition material 2 made of a porous non-conductive film. In the cathode chamber 3, a cathode 5 made of a conductive porous material is disposed so as to be in close contact with the partition material 2. The cathode chamber 3 between the cathode 5 and the wall surface of the tank body 1 is filled with the cathode solution. A diffuser tube 7 is provided in the lower part of the cathode chamber 3 so as to aerate the cathode solution. Oxygen-containing gas such as air is introduced into the aeration tube 7 and aeration exhaust gas flows out from the gas outlet 8 at the upper part of the cathode chamber. Since the cathode solution evaporates or scatters with aeration, the replenishment cathode solution is appropriately supplied from the replenishing port 16 having the valve 15.

An anode 6 made of a conductive porous material is disposed in the anode chamber 4. The anode 6 is in close contact with the partition material 2, and protons (H ⁺ ) can be transferred from the anode 6 to the partition material 2.

  Microorganisms are supported on the anode 6 made of this porous material. The anode solution L is introduced into the anode chamber 4 from the inlet 4a, and the waste liquid is discharged from the outlet 4b. The anode chamber 4 is anaerobic.

  The anode solution L in the anode chamber 4 is circulated through a circulation outlet 9, a circulation pipe 10, a circulation pump 11, and a circulation return 12. The circulation pipe 10 is provided with a pH meter 14 for measuring the pH of the liquid flowing out from the anode chamber 4 and connected with a pH regulator addition pipe 13 such as an alkali or an acid. In addition, a piping 19 for adding a bactericide is connected to the circulation piping 10. Note that the sterilizing agent addition pipe 19 may be directly connected to the anode chamber 4. However, the sterilizing agent can be supplied uniformly to the whole anode chamber 4 by adding the sterilizing agent to the circulating water.

  A diffuser pipe 17 is installed in the anode chamber 6, and the anode chamber 6 is aerated with an inert gas such as nitrogen by opening the valve portion 17 a. A gas outlet 18 having a valve 18 a is provided in the upper part of the anode chamber 6.

By supplying an oxygen-containing gas such as air to the aeration tube 7 to aerate the cathode solution in the cathode chamber 3, and operating the pump 11 as necessary to circulate the anode solution L,
(Organic) + H ₂ O → CO ₂ + H ⁺ + e ⁻
The reaction proceeds. The electrons e ⁻ flow to the cathode 5 through the anode 6, the terminal 22, the external resistor 21, and the terminal 20.

Proton H ⁺ generated by the above reaction moves to the cathode 5 through the partition material 2. In cathode 5,
O ₂ + 4H ⁺ + 4e ⁻ → 2H ₂ O
The reaction proceeds. Due to such a reaction, an electromotive force is generated between the cathode 5 and the anode 6, and a current flows to the external resistor 21 through the terminals 20 and 22.

  A disinfectant is preferably added to the anode chamber 4 preferably intermittently. Thereby, excessive adhesion of the power generation microorganisms to the anode surface is suppressed, and a high power generation amount can be stably maintained. In addition, in the anode chamber under anaerobic conditions, methane-producing bacteria may grow in addition to power-generating bacteria, which may reduce power generation efficiency. Bacterial growth is further suppressed, and the power generation efficiency can be kept high.

  As a bactericidal agent, an agent generally used as a slime control agent can be used. However, hydrogen peroxide, hypochlorous acid or a salt thereof, and the like can be used because of low cost and persistence and little influence on subsequent processing. Bromine acid or a salt thereof is preferred.

  The addition frequency of the sterilizing agent to the anode chamber is once every 2 hours to 30 days, preferably 6 hours to once a week, and the addition time per time is 1 minute to 1 hour, preferably 5 minutes to 30 minutes.

  The concentration added to the anode chamber inflow water depends on the type of the bactericidal agent, but is preferably 10 to 3,000 mg / L, more preferably 100 to 500 mg / L, hypochlorous acid or hypochlorous acid, as long as it is hydrogen peroxide. If it is a chlorate, Preferably it is 10-3,000 mg-effective chlorine / L, More preferably, it is 100-500 mg-effective chlorine / L.

In the anode chamber 4, the pH tends to change due to the generation of CO ₂ by the decomposition reaction of organic substances by microorganisms. Therefore, an alkali or an acid is added to the anode solution L so that the detected pH of the pH meter 14 is preferably 7-9. The alkali or acid may be added directly to the anode chamber 6, but by adding to the circulating water, the entire area in the anode chamber 4 can be maintained at pH 7 to 9 without partial deviation.

  Further, the valves 17 a and 18 a are opened continuously or intermittently, the inside of the anode chamber 6 is aerated by the inert gas from the diffuser tube 7, and the exhaust gas is caused to flow out from the gas outlet 18. As a result, shearing force due to gas is applied to the anode surface, and the effect of suppressing excessive adhesion of the biofilm is enhanced. In addition, when oxygen is used as an electron acceptor in the cathode chamber, the aerobic slime An effect of removing oxygen penetrating from the cathode chamber to the anode chamber, which leads to performance degradation due to proliferation or the like, is also achieved. Nitrogen is suitable as the inert gas, but is not limited thereto.

  FIG. 2 is a schematic cross-sectional view of a microbial power generation device according to another embodiment of the present invention.

  Two plate-shaped partition members 31 are arranged in parallel with each other in a substantially rectangular parallelepiped tank body 30, thereby forming an anode chamber 32 between the partition members 31, 31. Two cathode chambers 33 and 33 are formed by separating the partition member 31 from the partition member 32.

An anode 34 made of a porous material is disposed in the anode chamber 32 so as to be in close contact with each partition material 31. The anode 34 is lightly pressed against the partition material (for example, at a pressure of 0.1 kg / cm ² or less).

A cathode 35 made of a porous material is disposed in the cathode chamber 33 in contact with the partition material 31. The cathode 35 is pressed by a spacer 36 made of rubber or the like and is pressed lightly (for example, at a pressure of 0.1 kg / cm ² or less) against the partition material 31 to be in close contact therewith. In order to improve the adhesion between the cathode 35 and the partition material 31, they may be welded or partially bonded with an adhesive.

  The cathode 35 and the anode 34 are connected to an external resistor 38 via terminals 37 and 39.

  The space between the cathode 35 and the side wall of the tank body 30 is filled with the cathode solution. A diffuser tube 51 is installed in the lower part of each cathode chamber 33 so that the cathode solution can be aerated. The aerated exhaust gas flows out from the gas outlet 52 at the top of the cathode chamber 33. Although not shown, a replenishing port is provided for each cathode chamber 33 so as to replenish the cathode solution.

  An anode solution L is introduced into the anode chamber 32 from the inlet 32a, and the waste liquid flows out from the outlet 32b. The anode chamber 32 is anaerobic.

  The anode solution in the anode chamber 32 is circulated through a circulation outlet 41, a circulation pipe 42, a circulation pump 43, and a circulation return port 44. A sterilizing agent adding pipe 61 is connected to the circulating pipe 42. The circulation pipe 42 is provided with a pH meter 47 and an alkali addition pipe 45 is connected thereto. The pH of the anode solution flowing out from the anode chamber 32 is detected by a pH meter 47, and an alkali such as an aqueous sodium hydroxide solution is added so that this pH is preferably 7-9.

  A diffuser pipe 57 is installed in the anode chamber 32, and the anode chamber 32 is aerated with an oxygen-containing gas by opening the valve 57a. A gas outlet 58 having a valve 58 a is provided in the upper part of the anode chamber 32.

  2, the oxygen-containing gas is supplied to the diffuser pipe 51 to aerate the cathode solution in the cathode chamber 33, and the anode solution is circulated through the anode chamber 32, preferably the anode solution is circulated. As a result, a potential difference is generated between the cathode 35 and the anode 34, and a current flows through the external resistor 38.

  A disinfectant is preferably added intermittently from the pipe 61, the valves 57a and 58a are intermittently opened, the inside of the anode chamber 32 is aerated by the inert gas from the air diffuser 57, and the exhaust gas is discharged from the gas outlet 58. Spill.

  In FIGS. 1 and 2, the aeration tube is disposed in the cathode chambers 3 and 33 and the cathode solution is aerated in the cathode chambers 3 and 33, but the cathode solution in the cathode chamber is introduced into another aeration chamber. It may be aerated.

  Next, in addition to the microorganisms, anode solution, cathode solution, and the like of the microorganism power generation apparatus of the present invention, suitable materials for the partition material, anode, and cathode will be described.

  The microorganism that produces electric energy by being contained in the anode solution L is not particularly limited as long as it has a function as an electron donor. For example, Saccharomyces, Hansenula, Candida, Micrococcus, Staphylococcus, Streptococcus, Leuconostoa, Lactobacillus, Corynebacterium, Arthrobacter, Bacillus, Clostridium, Neisseria, Escherichia, Enterobacter, Serratia, Aigenes Examples include bacteria, filamentous fungi, and yeasts belonging to the genera Gluconobacter, Pseudomonas, Xanthomonas, Vibrio, Comamonas, and Proteus (Proteus vulgaris). The activated sludge obtained from a biological treatment tank that treats organic matter-containing water such as sewage as sludge containing such microorganisms, microorganisms contained in the effluent from the first sedimentation basin of sewage, anaerobic digested sludge, etc. The chamber can be fed and microorganisms can be retained on the anode. In order to increase the power generation efficiency, the amount of microorganisms retained in the anode chamber is preferably high, and for example, the microorganism concentration is preferably 1 to 50 g / L.

  As the anode solution L, a solution that retains microorganisms or cells and has a composition necessary for power generation is used. For example, when generating electricity in the respiratory system, the anode solution may be an energy source necessary for performing respiratory metabolism such as bouillon medium, M9 medium, L medium, Malt Extract, MY medium, and nitrifying bacteria selection medium. A medium having a composition such as nutrients can be used. In addition, organic waste such as sewage, organic industrial wastewater, and garbage can be used.

  The anode solution L may contain an electron mediator in order to make it easier to extract electrons from microorganisms or cells. Examples of the electron mediator include compounds having a thionin skeleton such as thionine, dimethyldisulfonated thionine, new methylene blue and toluidine blue-O, and 2-hydroxy-1,4-naphthoquinone such as 2-hydroxy-1,4-naphthoquinone. Examples include compounds having a skeleton, brilliant cresyl blue, galocyanine, resorufin, alizarin brilliant blue, phenothiazinone, phenazine esosulphate, safranin-O, dichlorophenolindophenol, ferrocene, benzoquinone, phthalocyanine, or benzyl viologen and their derivatives. be able to.

  Furthermore, if materials that increase the power generation function of microorganisms, such as antioxidants such as vitamin C, or materials that increase the function of only specific electron transfer systems or substance transfer systems in microorganisms, are dissolved, power can be more efficiently generated. Is preferable.

  The anodic solution L may contain a phosphate buffer as necessary.

  The anode solution L contains an organic substance. The organic substance is not particularly limited as long as it can be decomposed by microorganisms. For example, water-soluble organic substances, organic fine particles dispersed in water, and the like are used. The anodic solution may be an organic effluent such as sewage or food factory effluent. The organic substance concentration in the anode solution L is preferably a high concentration of about 100 to 10000 mg / L in order to increase the power generation efficiency.

  The temperature of the anode solution is preferably about 10 to 70 ° C.

  The catholyte solution is preferably neutral or alkaline, for example, pH 6.0 to 9.0, and may contain a buffer in order to keep the pH in such a range.

  Further, the cathode solution may contain a redox reagent such as potassium ferricyanide, manganese sulfate, manganese chloride, ferric chloride, ferric sulfate as an electron acceptor. In this case, the redox reagent concentration in the cathode solution is preferably about 10 to 2,000 mM.

  The catholyte solution may also contain a chelating agent. By blending a chelating agent, tetravalent manganese can be present in a dissolved state, and the effect of increasing the speed of the reduction reaction can be obtained.

  Any chelating agent can be used without limitation as long as it forms a chelate compound with manganese ions. Specifically, ethylenediaminetetraacetic acid (EDTA), 1,2-dihydroxyanthraquinone-3-yl-methylamino-N, N′-diacetic acid, 5,5′-dibromopyrogallolsulfophthalein, 1- (1- Hydroxy-2-naphthylazo) -6-nitro-2-naphthol-4-sulfonic acid sodium salt, cyclo-tris- [7- (1-azo-8-hydroxynaphthalene-3,6-disulfonic acid)] 6 sodium salt 4-Methylumbelliferone-8-methyleneiminodiacetic acid, 3-sulfo-2,6-dichloro-3 ′, 3 ″ -dimethyl-4′-fuxone-5 ′, 5 ″ -dicarboxylic acid trisodium salt Salt, 3,3′-bis [N, N-di (carboxymethyl) aminomethyl] thymol sulfonephthalein, sodium salt, 7- (1-naphthylazo) -8-hydroxyquinoline-5-sulfonic acid sodium salt 4- (2-pi Jiruazo) resorcinol, pyrocatechol sulfone phthalein, 3,3'-bis [N, N-di (carboxymethyl) aminomethyl] - ortho - cresol sulfonic phthalein, etc. disodium salt. The chelating agent is preferably a stable one that is not easily biodegradable.

  Air is suitable as the oxygen-containing gas supplied to the cathode. The exhaust gas from the cathode chamber may be deoxygenated as necessary, and then vented to the anode chamber to be used for purging dissolved oxygen from the anode solution L. The supply amount of the oxygen-containing gas may be such that DO is detected (for example, 0.5 mg / L or less) when the dissolved oxygen (DO) concentration of the cathode solution is measured.

  As the partition material, paper, woven fabric, non-woven fabric, so-called organic membrane (microfiltration membrane), honeycomb molded body, lattice-shaped molded body and the like made of a porous non-conductive material can be used. As the partition material, a material made of a hydrophilic material is used because of easy proton movement, or a microfiltration membrane in which a hydrophobic membrane is made hydrophilic is preferable. When using a hydrophobic material, it is good to process it so that water can pass easily as shapes, such as a woven fabric, a nonwoven fabric, and a honeycomb. Specific examples of the non-conductive material include polyethylene, polypropylene, polycarbonate, polyethersulfone (PES), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyvinyl alcohol (PVA), and cellulose. Cellulose acetate and the like are preferable. In order to facilitate the permeation of protons, the partition material is preferably a thin material having a thickness of 10 μm to 10 mm, particularly about 30 to 100 μm.

  When organic wastewater is used as the anode solution, in order to prevent clogging due to suspended substances, etc., the partition material is excellent in water permeability with a thickness of about 1 to 10 mm, such as a honeycomb or lattice. Is preferred. When waste water is not used as the anode solution, the partition material is optimally paper having a thickness of 1 mm or less in terms of thickness and price. Moreover, since the microfiltration membrane which hydrophilized PES and PVDF is very thin, it is suitable as a partition material in the case of calculating | requiring high output. Furthermore, a nonwoven fabric made of polyethylene or polypropylene is preferable in terms of cost.

  The anode is preferably a porous body having a large surface area and a large number of voids and water permeability so that a large number of microorganisms can be retained. Specific examples include a conductive material sheet having a roughened surface and a porous conductor (for example, graphite felt, expanded titanium, expanded stainless steel, etc.) in which the conductive material is made into a felt-like porous sheet. . When such a porous anode is brought into close contact with the partition material, electrons generated by the microbial reaction can be passed to the anode without using an electron mediator, and the electron mediator can be dispensed with.

  The anode is preferably made of a fibrous body such as felt. When the anode has a thickness larger than the thickness of the anode chamber, the anode is compressed and inserted into the anode chamber, and comes into close contact with the partition material by its own restoring elasticity.

  A plurality of sheet-like conductors may be laminated to form an anode. In this case, the same kind of conductor sheets may be laminated, or different kinds of conductor sheets (for example, a graphite sheet having a rough surface and a graphite felt) may be laminated.

  The anode preferably has a total thickness of 3 mm to 50 mm, particularly about 5 to 40 mm. When the anode is constituted by a laminated sheet, the laminated surface is preferably oriented in a direction connecting the liquid inlet and the outlet so that the liquid flows along a mating surface (laminated surface) between the sheets.

  The cathode is made of a felt-like or porous conductive material such as graphite felt, stainless steel foam, and titanium foam. In the case of a porous material, the void diameter is preferably about 0.01 to 1 mm. As the cathode, it is preferable to use a cathode in which these conductive materials are formed in a shape (for example, a plate shape) that is easily adhered to the partition material. When oxygen is used as an electron acceptor, an oxygen reduction catalyst is preferably used. For example, the catalyst may be supported using graphite felt as a base material. Examples of the catalyst include noble metals such as platinum, metal oxides such as manganese dioxide, and carbon-based materials such as activated carbon. Depending on the type of electron acceptor, for example, when a liquid containing potassium hexacyanoferrate (III) (potassium ferricyanide) is used, an inexpensive graphite electrode may be used as it is (without supporting platinum) as a cathode. The thickness of the cathode is preferably 0.03 to 50 mm.

  1 and 2 both show a microbial power generation apparatus in which a cathode solution is held in the cathode chamber, but the present invention is not limited to such a microbial power generation apparatus, and the cathode chamber is an empty room. The present invention can also be applied to an air cathode type microbial power generation apparatus that circulates air.

  Hereinafter, comparative examples and examples will be described.

[Comparative Example 1]
A 7 cm × 25 cm × 1 cm (thickness) anode chamber was filled with two 1 cm thick graphite felts to form an anode. A cathode chamber was formed on the anode chamber through a nonwoven fabric having a thickness of 30 μm. The cathode chamber also has a size of 7 cm × 25 cm × 1 cm (thickness), and was filled with two 10 mm thick graphite felts to form a cathode. A stainless steel wire was bonded to the graphite felt of the anode and the cathode with a conductive paste to form an electrical lead wire and connected with a resistance of 3Ω.

  Raw water containing 1,000 mg / L of acetic acid, 50 mM phosphate buffer and ammonium chloride was passed through the anode chamber, maintaining the pH at 7.5. This raw water was heated to 35 ° C. in a separate water tank in advance and then passed through the anode chamber at 70 mL / min, thereby heating the anode chamber to 35 ° C. Prior to the flow of the raw water, the effluent of another microbial power generation device was passed as an inoculum. A cathode solution containing 50 mM potassium ferricyanide and a phosphate buffer was supplied to the cathode chamber at a flow rate of 70 mL / min.

Power generation amount, 300 W / ^{m 3} at 1 week after passing water starts - anode chamber volume (. Which hereinafter referred to as W / ^{m 3)} to reach, but remained in the subsequent 6 weeks 280~330W / ^{m 3,} then 2 It decreased to 100 W / m ^{3 in a} week. When the device was disassembled and the anode was taken out, the graphite felt was covered with a thick biofilm, and it was confirmed that a water channel was formed in a part of the felt. It is thought that the amount of attached organisms increased to cover the negative electrode, and the flow of water and the contact efficiency with the substrate were reduced.

[Example 1]
With the same configuration as Comparative Example 1, one week passed after the start of water flow, and when it reached 300 W / m ³ , once every 12 hours for 10 minutes, the concentration after addition to the anode chamber inflow water was 100 mg / L. Hydrogen peroxide was added so that Immediately after the addition, the power generation amount decreased greatly, but recovered to the original value in about 30 minutes, and the power generation amount remained at 280 to 330 W / m ³ over the next five months. When the device was disassembled and the negative electrode was taken out, the amount of biofilm attached was small compared to the comparative example, and the state where water flowed into the graphite felt was maintained.

[Example 2]
With the same configuration as that of the comparative example, nitrogen gas was passed through the anode chamber with an air volume of 200 mL / min. When it reached 300 W / m ³ in one week after the start of water flow, hydrogen peroxide was added once a day for 10 minutes so that the concentration after addition to the anode chamber influent water was 100 mg / L. Immediately after the addition, the power generation amount decreased greatly, but recovered to the original value in about 30 minutes, and the power generation amount remained at 280 to 330 W / m ³ over the next five months. When the device was disassembled and the negative electrode was taken out, the amount of biofilm attached was small compared to the comparative example, and the state where water flowed into the graphite felt was maintained.

[Example 3]
In the same configuration as the comparative example, when 300 W / m ³ was reached in one week after the start of water flow, the concentration after addition to the anode chamber inflow water was 300 mg-effective chlorine / L once a week for 30 minutes. Sodium hypochlorite was added as follows. Immediately after the addition, the power generation amount decreased greatly, but recovered to the original value in 1 to 2 hours. Thereafter, the power generation amount remained at 280 to 330 W / m ³ over 5 months. When the device was disassembled and the negative electrode was taken out, the amount of biofilm attached was small compared to the comparative example, and the state where water flowed into the graphite felt was maintained.

  From the above comparative examples and examples, it is confirmed that the present invention suppresses excessive adhesion of microorganisms to the anode surface in the anode chamber of the microbial power generation apparatus, and can stably obtain a high power generation amount for a long period of time. It was done.

DESCRIPTION OF SYMBOLS 1,30 Tank 2,31 Partition material 3,33 Cathode chamber 4,32 Anode chamber 5,35 Cathode 6,34 Anode 7,17,51,57 Air diffuser 9,61 Piping for adding bactericide

In one aspect of the present invention, a bactericidal agent is supplied to the anode chamber at a frequency of once every 2 hours to 30 days for 1 minute to 1 hour.

Trachea 17 diffusing to the anode chamber 4 and is installed, the anode chamber 4 with an inert gas such as nitrogen is configured to be aerated by the valves 1 7a opened. A gas outlet 18 having a valve 18 a is provided in the upper part of the anode chamber 4 .

Further, the valves 17 a and 18 a are opened continuously or intermittently, the inside of the anode chamber 4 is aerated by the inert gas from the diffuser pipe 7, and the exhaust gas is caused to flow out from the gas outlet 18. As a result, shearing force due to gas is applied to the anode surface, and the effect of suppressing excessive adhesion of the biofilm is enhanced. In addition, when oxygen is used as an electron acceptor in the cathode chamber, the aerobic slime An effect of removing oxygen penetrating from the cathode chamber to the anode chamber, which leads to performance degradation due to proliferation or the like, is also achieved. Nitrogen is suitable as the inert gas, but is not limited thereto.

A diffuser tube 57 is installed in the anode chamber 32, and the anode chamber 32 is aerated with an inert gas by opening the valve 57a. A gas outlet 58 having a valve 58 a is provided in the upper part of the anode chamber 32.

Claims (7)

An anode chamber having an anode and holding a liquid containing a microorganism and an electron donor; and a cathode chamber separated from the anode chamber by a porous non-conductive membrane;
In the microbial power generation apparatus for supplying the organic material-containing raw water to the anode chamber and generating a power by supplying a fluid containing an electron acceptor to the cathode chamber,
A microbial power generation apparatus comprising a sterilizing agent supplying means for supplying a sterilizing agent into the anode chamber.   The microbial power generation apparatus according to claim 1, wherein the bactericide is hydrogen peroxide, hypochlorous acid or hypochlorite.   The microbial power generation apparatus according to claim 1 or 2, further comprising means for supplying an inert gas to the anode chamber. An anode chamber having an anode and holding a liquid containing a microorganism and an electron donor; and a cathode chamber separated from the anode chamber by a porous non-conductive membrane;
In the operation method of the microbial power generation apparatus for supplying the organic material-containing raw water to the anode chamber and supplying the fluid containing the electron acceptor to the cathode chamber to generate power,
A method for operating a microbial power generation apparatus, wherein a bactericide is intermittently supplied into the anode chamber.   The method for operating a microbial power generation apparatus according to claim 4, wherein the sterilizing agent is supplied to the anode chamber at a frequency of once every 2 hours to 30 times for 1 minute to 1 hour.   The method for operating a microbial power generation apparatus according to claim 4 or 5, wherein the bactericide is hydrogen peroxide, hypochlorous acid or hypochlorite.   The method for operating a microbial power generation device according to any one of claims 4 to 6, wherein an inert gas is supplied continuously or intermittently to the anode chamber.

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