Microbial power generation device and operation method thereof

Abstract

A microbial power generation device comprises: an anode chamber (4) having an anode (6) and holding a liquid containing microorganisms and an electron donor, and a cathode chamber (3) separated from the anode chamber (4) via an ion-permeable non-conductive membrane (2). Raw water containing organic matter is supplied to the anode chamber (4), and a fluid containing an electron acceptor is supplied to the cathode chamber (3) to generate electricity. In the microbial power generation device, the anode chamber (4) is intermittently aerated by oxygen-containing gas from a diffusion pipe (17).

Description

Technical Field

[0001] The present invention relates to a power generation device utilizing the metabolic reaction of microorganisms and an operating method thereof. In particular, the present invention relates to a microbial power generation device that extracts reducing power obtained by oxidizing and decomposing organic matter as electrical energy and an operating method thereof. Background Art

[0002] As power generation devices using microorganisms, Patent Documents 1 and 2 describe devices in which a cathode chamber and an anode chamber are divided by an electrolyte membrane.

[0003] Patent Document 1 describes that by adjusting the pH in the anode chamber to 7 to 9, a pH drop caused by carbon dioxide gas generated in association with a microbial reaction in the anode chamber is prevented, thereby improving power generation efficiency.

[0004] Patent document 1: Japanese Patent Laid-Open No. 2009-152097;

[0005] Patent document 2: Japanese Patent Application Publication No. 2000-133326.

[0006] During the long-term operation of the microbial power generation device, in the anode chamber under anaerobic conditions, methanogens will proliferate using organic matter as a substrate. Since organisms other than power generation microorganisms proliferate on the electrode surface, the internal resistance increases, and the organic matter that should be used for power generation reaction is consumed by methanogens, resulting in a decrease in power generation efficiency. Summary of the invention

[0007] An object of the present invention is to provide a microbial power generation device and an operating method thereof, which can suppress the proliferation of methane-producing bacteria in an anode chamber of the microbial power generation device and obtain high power generation in a stable manner for a long period of time.

[0008] The microbial power generation device of the present invention includes an anode chamber having an anode and holding a liquid containing microorganisms and an electron donor, and a cathode chamber separated from the anode chamber by a porous non-conductive membrane, and raw water containing organic matter is supplied to the anode chamber, and a fluid containing an electron acceptor is supplied to the cathode chamber to generate electricity. The microbial power generation device is characterized in that it includes: an oxygen supply unit that intermittently supplies oxygen to the anode chamber.

[0009] In one embodiment of the present invention, the oxygen supply unit is an oxygen-containing gas aeration unit.

[0010] In one aspect of the present invention, the oxygen supply means is a supply means for oxygen-dissolved water.

[0011] The method for operating a microbial power generation device of the present invention comprises an anode chamber having an anode and holding a liquid containing microorganisms and an electron donor, and a cathode chamber separated from the anode chamber by a porous non-conductive membrane, and raw water containing organic matter is supplied to the anode chamber, and a fluid containing an electron acceptor is supplied to the cathode chamber to generate electricity. The method for operating the microbial power generation device is characterized in that oxygen is intermittently supplied to the anode chamber.

[0012] In one embodiment of the present invention, the oxygen-containing gas is supplied to the anode chamber at a frequency of once every 2 hours to 30 days for 30 seconds to 12 hours each time.

[0013] In one aspect of the present invention, oxygen is supplied so that the dissolved oxygen concentration in the anode chamber becomes 2 mg / L to 8 mg / L.

[0014] Effects of the Invention

[0015] In the present invention, oxygen is intermittently supplied to the anode chamber. This can suppress the growth of methane-producing bacteria, which are strictly anaerobic bacteria. There are also facultative anaerobic bacteria among the power generation microorganisms that can survive under aerobic conditions, and thus the power generation reaction in the anode chamber can be stably maintained. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic cross-sectional view of a microbial power generation device according to an embodiment of the present invention.

[0017] Figure 2 This is a schematic cross-sectional view of a microbial power generation device according to one embodiment of the present invention. DETAILED DESCRIPTION

[0018] Hereinafter, the present invention will be described in more detail.

[0019] Figure 1 This is a schematic cross-sectional view showing a schematic configuration of a microbial power generation device according to an embodiment of the present invention.

[0020] The tank body 1 is divided into a cathode chamber 3 and an anode chamber 4 by a separator 2 including a porous non-conductive membrane. In the cathode chamber 3, a cathode 5 including a conductive porous material is arranged in close contact with the separator 2. The cathode chamber 3 between the cathode 5 and the wall surface of the tank body 1 is filled with a cathode solution. In order to aerate the cathode solution, a diffusion pipe 7 is provided at the lower part of the cathode chamber 3. An oxygen-containing gas such as air is introduced into the diffusion pipe 7, and the aeration exhaust gas flows out from the gas outflow port 8 at the upper part of the cathode chamber. As the cathode solution evaporates or scatters with aeration, it decreases, so the cathode solution for replenishment is appropriately supplied from the supply port 16 having a valve 15.

[0021] 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 separator 2, so that protons (H + ).

[0022] The anode 6 composed of the porous material carries microorganisms. 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 inside of the anode chamber 4 is anaerobic.

[0023] The anode solution L in the anode chamber 4 circulates via the circulation outlet 9, the circulation pipe 10, the circulation pump 11 and the circulation return port 12. The circulation pipe 10 is provided with a pH meter 14 for measuring the pH of the liquid flowing out of the anode chamber 4, and is connected to a pipe 13 for adding a pH adjuster such as an alkali or an acid.

[0024] The anode chamber 4 is provided with a diffusion pipe 17, and by opening a valve 17a, the anode chamber 4 is aerated with an oxygen-containing gas. A gas outlet 18 having a valve 18a is provided at an upper portion of the anode chamber 4.

[0025] By supplying oxygen-containing gas such as air to the diffusion pipe 7, the cathode solution in the cathode chamber 3 is aerated, and the pump 11 is operated as needed to circulate the anode solution L, thereby performing (organic matter) + H2O → CO2 + H + +e - The electron e - The electric current flows to the cathode 5 via the anode 6 , the terminal 22 , the external resistor 21 , and the terminal 20 .

[0026] The protons H generated in the reaction + Move to cathode 5 through separator 2. In cathode 5, O2+4H + +4e - →2H2O reaction. This reaction generates an electromotive force between the cathode 5 and the anode 6, and current flows to the external resistor 21 via the terminals 20 and 22.

[0027] In the anode chamber 4, CO2 is produced by the decomposition reaction of organic matter caused by microorganisms, and the pH changes. Therefore, alkali or acid is added to the anode solution L in such a way that the pH detected by the pH meter 14 is preferably 7 to 9. The alkali or acid may be directly added to the anode chamber 4, but by adding it to the circulating water, the entire area in the anode chamber 4 can be maintained at pH 7 to pH 9 without local unevenness.

[0028] The valves 17a and 18a are intermittently opened to aerate the anode chamber 4 with oxygen-containing gas from the diffusion pipe 17, and exhaust gas is discharged from the gas outlet 18. This suppresses the growth of methanogens in the anode chamber 4. The aeration causes the anode chamber 4 to temporarily be in an aerobic state, and the power generation decreases. However, after the aeration is stopped and DO is consumed, the power generation recovers rapidly.

[0029] Figure 2 This is a schematic cross-sectional view of a microbial power generation device according to another embodiment of the present invention.

[0030] Two plate-like separators 31 are arranged parallel to each other in a substantially rectangular tank body 30 to form an anode chamber 32 between the separators 31 and two cathode chambers 33 are formed with the separators 31 interposed therebetween.

[0031] In the anode chamber 32, an anode 34 made of a porous material is arranged in close contact with each separator 31. The anode 34 is gently (for example, at 0.1 kg / cm 2 The following pressure) is pressed to the separator material.

[0032] In the cathode chamber 33, a cathode 35 made of a porous material is arranged in contact with the separator 31. The cathode 35 is pressed by a spacer 36 made of rubber or the like and is gently (for example, at 0.1 kg / cm 2 The cathode 35 is pressed with a pressure of 0.1% or less to be in close contact with the separator 31. In order to improve the close contact between the cathode 35 and the separator 31, the two may be welded or partially bonded with an adhesive.

[0033] The cathode 35 and the anode 34 are connected to an external resistor 38 via a terminal 37 and a terminal 39 .

[0034] The cathode chamber 33 between the cathode 35 and the side wall of the tank body 30 is filled with a cathode solution. A diffuser 51 is provided at the lower part of each cathode chamber 33 to aerate the cathode solution. Aeration exhaust flows out from a gas outlet 52 at the upper part of the cathode chamber 33. Although not shown in the figure, a replenishing port is provided in order to replenish the cathode solution to each cathode chamber 33.

[0035] The anode solution L is introduced into the anode chamber 32 from the inlet 32a, and waste liquid flows out from the outlet 32b. The inside of the anode chamber 32 is anaerobic.

[0036] The anode solution in the anode chamber 32 circulates through the circulation outlet 41, the circulation pipe 42, the circulation pump 43 and the circulation return port 44. The circulation pipe 42 is provided with a pH meter 47 and is connected to an alkali addition pipe 45. The pH of the anode solution flowing out of the anode chamber 32 is detected by the pH meter 47, and an alkali such as an aqueous sodium hydroxide solution is added so that the pH is preferably 7 to 9.

[0037] The anode chamber 32 is provided with a diffusion pipe 57, and by opening a valve 57a, the anode chamber 32 is aerated with an oxygen-containing gas. A gas outlet 58 having a valve 58a is provided at an upper portion of the anode chamber 32.

[0038] exist Figure 2 In the microbial power generation device, oxygen-containing gas is also supplied to the diffusion pipe 51 to aerate the cathode solution in the cathode chamber 33, and the anode solution is circulated in the anode chamber 32, preferably the anode solution is circulated, thereby generating a potential difference between the cathode 35 and the anode 34, and current flows to the external resistor 38.

[0039] The valves 57a and 58a are intermittently opened to aerate the anode chamber 32 with the oxygen-containing gas from the diffusion pipe 57, and the exhaust gas is discharged from the gas outlet 58. Thus, the growth of the methane-producing bacteria in the anode chamber 32 is suppressed.

[0040] exist Figure 1 , Figure 2 In the embodiment, the diffusion pipe is arranged in the cathode chamber 3 and the cathode chamber 33, and the cathode solution is aerated in the cathode chamber 3 and the cathode chamber 33, but the cathode solution in the cathode chamber can also be introduced into other aeration chambers for aeration.

[0041] exist Figure 1 , Figure 2 In the microbial power generation device shown, by intermittently aerating the inside of the anode chamber 4 and the anode chamber 322 as described above, a decrease in power generation due to the proliferation of methane-producing bacteria is prevented, and the power generation efficiency can be stably maintained.

[0042] The oxygen-containing gas may be any of air, oxygen, oxygen-enriched air, etc., but is preferably air.

[0043] The frequency of supplying oxygen-containing gas to the anode chamber is once every 2 hours to 30 days, and the supply time of oxygen-containing gas each time is preferably 30 seconds to 12 hours, more preferably once every 6 hours to 3 days, and each time is 1 minute to 2 hours.

[0044] Preferably, the oxygen-containing gas is supplied so that the dissolved oxygen concentration in the anode chamber is 2 mg / L to 8 mg / L, particularly 4 mg / L to 8 mg / L.

[0045] In the above embodiment, the oxygen-containing gas is supplied to the anode chamber through the diffuser pipe 17 and the diffuser pipe 57, but the aeration tank may be provided in the circulation pipe 10 and the circulation pipe 42 of the anode solution to perform aeration with the oxygen-containing gas. The circulation pipe 10 and the circulation pipe 42 may be connected to the oxygen-containing gas inflow pipe, and a line mixer may be provided in the circulation pipe on the downstream side of the oxygen-containing gas inflow pipe. Furthermore, oxygen-dissolved water may be flowed into the anode chamber or the circulation pipe.

[0046] Next, the microorganisms, anode solution, cathode solution, etc., as well as separators, and suitable materials for the anode and cathode, etc. of the microbial power generation device of the present invention are described.

[0047] The microorganisms that generate electric energy by being contained in the anode solution L are not particularly limited as long as they have the function of being electron donors. For example, the microorganisms that can be mentioned include: microorganisms belonging to the genus Saccharomyces, the genus Hansenula, the genus Candida, the genus Micrococcus, the genus Staphylococcus, the genus Streptococcus, the genus Leuconostoa, the genus Lactobacillus, the genus Corynebacterium, the genus Arthrobacter, the genus Bacillus, the genus Clostridium, the genus Neisseria, the genus Escherichia, the genus Enterobacter, the genus ), Serratia, Achromobacter, Alcaligenes, Flavobacterium, Acetobacter, Moraxella, Nitrosomonas, Nitorobacter, Thiobacillus, Gluconobacter, Pseudomonas, Xanthomonas, Vibrio, Comamonas, and Proteus (Proteus vulgaris) bacteria, filamentous fungi, yeast, etc. The activated sludge obtained from a biological treatment tank for treating organic matter such as sewage, the microorganisms contained in the outflow water from the initial sedimentation tank of sewage, the anaerobic digestion sludge, etc., which is the sludge containing such microorganisms, is supplied to the anode chamber in the form of inoculation, so that the microorganisms are retained in the anode. In order to improve the power generation efficiency, the amount of microorganisms retained in the anode chamber is preferably high, for example, the microorganism concentration is preferably 1g / L to 50g / L.

[0048] As the anode solution L, a solution having a composition required for power generation and capable of maintaining microorganisms or cells is used. For example, when power generation of the respiratory system is performed, a culture medium having a composition of an energy source and nutrients required for the metabolism of the respiratory system, such as bouillon culture medium, M9 culture medium, L culture medium, malt extract, MY culture medium, nitrifying bacteria selective culture medium, etc., can be used as the anode solution. In addition, organic wastes such as sewage, organic industrial drainage, and domestic garbage can be used.

[0049] The anode solution L may contain an electron mediator in order to more easily extract electrons from microorganisms or cells. Examples of the electron mediator include compounds having a thionine skeleton such as thionine, dimethyl disulfonated thionine, new methylene blue, and toluidine blue O, compounds having a 2-hydroxy-1,4-naphthoquinone skeleton such as 2-hydroxy-1,4-naphthoquinone, brilliant cresyl blue, gallocyanine, resorufin, alizarine brilliant blue, phenothiazinone, phenazine ethosulfate, safranin-O, dichlorophenol indophenol, ferrocene, benzoquinone, phthalocyanine, benzyl viologen, and derivatives thereof.

[0050] If a material that enhances the power generation function of the microorganisms, such as an antioxidant such as vitamin C, or a function-enhancing material that only enables a specific electron transfer system or substance transfer system in the microorganisms is dissolved in the anode solution L, electricity can be obtained more efficiently, which is preferred.

[0051] The anode solution L may also contain a phosphate buffer as necessary.

[0052] The anode solution L is a solution containing organic matter. As the organic matter, there is no particular limitation as long as it is an organic matter that is decomposed by microorganisms, and for example, water-soluble organic matter, organic matter particles dispersed in water, etc. can be used. The anode solution can also be organic waste liquid such as sewage, food factory drainage, etc. In order to improve the power generation efficiency, the organic matter concentration in the anode solution L is preferably a high concentration of about 100 mg / L to 10000 mg / L.

[0053] The temperature of the anode solution is preferably about 10°C to 70°C.

[0054] The cathode solution is neutral or alkaline, and preferably has a pH of 6.0 to 9.0, for example, and may contain a buffer solution in order to maintain the pH within this range.

[0055] The cathode solution may contain a redox reagent such as potassium ferricyanide, manganese sulfate, manganese chloride, ferric chloride, ferric sulfate, etc. as an electron acceptor. In this case, the concentration of the redox reagent in the cathode solution is preferably about 10 mM to 2000 mM.

[0056] The cathode solution may contain a chelating agent. By adding the chelating agent, tetravalent manganese can be present in a dissolved state, thereby achieving an effect of increasing the speed of the reduction reaction.

[0057] As the chelating agent, any chelating agent can be used without limitation as long as it can form a chelate compound with manganese ions. Specifically, ethylenediaminetetraacetic acid (EDTA), 1,2-dihydroxyanthraquinone-3-yl-methylamino-N,N'-diacetic acid, 5,5'-dibromo pyrogallol sulfonate (5,5'-Dibromo pyrogallol sulfophthalein), 1-(1-hydroxy-2-naphthylazo)-6-nitro-2-naphthol-4-sulfonic acid sodium salt, cyclotri-[7-(1-azo-8-hydroxynaphthalene-3,6-disulfonic acid)] hexasodium salt, 4-methylumbelliferyl-8-methyleneiminodiacetic acid, 3-sulfo-2,6-dichloro-3',3"-dimethyl-4'-fumarone-5',5"-dicarboxylic acid trisodium salt, 3,3'-bis[N,N-di(carboxymethyl)aminomethyl]thymolsulfonphthalein, sodium salt, 7-(1-naphthylazo)-8-hydroxyquinoline-5-sulfonic acid sodium salt, 4-(2-pyridylazo)resorcinol, catecholsulfonphthalein, 3,3'-bis[N,N-di(carboxymethyl)aminomethyl]-o-cresolsulfonphthalein, disodium salt, etc. The chelating agent is preferably a stable chelating agent that is not easily biodegradable.

[0058] Air is suitable as the oxygen-containing gas supplied to the cathode chamber. The exhaust gas from the cathode chamber may be deoxygenated as needed and then ventilated to the anode chamber for purging dissolved oxygen from the anode solution L. The supply amount of the oxygen-containing gas may be such that the dissolved oxygen (DO) concentration of the cathode solution can be detected (e.g., less than 0.5 mg / L) when the DO concentration is measured.

[0059] As the separator, paper, woven fabric, nonwoven fabric, so-called organic membrane (precision filtration membrane), honeycomb molded body, lattice molded body, etc. including porous non-conductive materials can be used. As the separator, in terms of the ease of proton movement, it is preferred to use a material composed of a hydrophilic material or a precision filtration membrane obtained by hydrophilizing a hydrophobic membrane. In the case of using a hydrophobic material, it is preferably processed into a shape such as a woven fabric, a nonwoven fabric, a honeycomb, etc. so that water can pass easily. As the non-conductive material, specifically, polyethylene, polypropylene, polycarbonate, polyethersulfone (PES), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyvinyl alcohol (PVA), cellulose, cellulose acetate, etc. are suitable. In order to make it easy for protons to pass through, the separator preferably has a thickness of 10μm to 10mm, especially a thin material of about 30μm to 100μm.

[0060] When organic wastewater is used as the anode solution, in order to prevent clogging caused by suspended matter, it is preferred to use a material such as a honeycomb or lattice with a thickness of about 1 mm to 10 mm and excellent water permeability as a separator. When wastewater is not used as the anode solution, paper with a thickness of less than 1 mm is most suitable as a separator in terms of thickness and price. In addition, since the precision filtration membrane obtained by hydrophilizing PES and PVDF is extremely thin, it is suitable as a separator when high output is required. In terms of cost, non-woven fabrics made of polyethylene or polypropylene are suitable.

[0061] The anode is preferably a porous body with a large surface area, a large number of voids, and water permeability, so as to be able to hold a large number of microorganisms. Specifically, a sheet of a conductive material having at least a roughened surface or a conductive material made into a felt (felt) shape and other porous sheets (e.g., graphite felt, foamed titanium, foamed stainless steel, etc.) can be cited. When such a porous anode is brought into close contact with a separator, without using an electron mediator, the electrons generated by the microbial reaction will be transferred to the anode, so that an electron mediator is not required.

[0062] The anode preferably includes a fibrous body such as felt. When the anode has a thickness greater than that of the anode chamber, it is compressed and inserted into the anode chamber, and comes into close contact with the separator due to its own restoring elasticity.

[0063] The anode may be formed by stacking a plurality of sheet-like conductors. In this case, the same type of conductor sheets may be stacked, or different types of conductor sheets (eg, graphite felt and graphite sheets having a rough surface) may be stacked.

[0064] The overall thickness of the anode is preferably 3 mm to 50 mm, particularly preferably about 5 mm to 40 mm. In the case of forming the anode by stacking sheets, in order to allow the liquid to flow along the bonding surface (stacked surface) between the sheets, it is preferred that the stacked surface is oriented in the direction connecting the inlet and outlet of the liquid.

[0065] The cathode is composed of a felt-like or porous conductive material such as graphite felt, foamed stainless steel, foamed titanium, etc. In the case of a porous material, the diameter of the void is preferably about 0.01 mm to 1 mm. As a cathode, it is preferred to use a cathode obtained by molding these conductive materials into a shape (such as a plate) that is easy to be in close contact with the separator. In the case of using oxygen as an electron acceptor, it is preferred to use an oxygen reduction catalyst, for example, graphite felt is preferably used as a substrate to load the catalyst. As a catalyst, carbon materials such as noble metals such as platinum, metal oxides such as manganese dioxide, and activated carbon can be exemplified. Depending on the type of electron acceptor, for example, when using a liquid containing potassium hexacyanoferrate (III) (potassium ferrocyanide), a cheap graphite electrode can be used directly (without loading platinum) as a cathode. The thickness of the cathode is preferably 0.03 mm to 50 mm.

[0066] Figure 1 , Figure 2 In all the above, a microbial power generation device in which a cathode solution is held in a cathode chamber is shown, but the present invention is not limited to such a microbial power generation device, and can also be applied to an air cathode type microbial power generation device in which air is passed through the cathode chamber as an empty chamber.

[0067] Example

[0068] Hereinafter, comparative examples and examples will be described.

[0069] [Comparative Example 1]

[0070] In the anode chamber of 7cm×25cm×2cm (thickness), two sheets of 1cm thick graphite felt were overlapped to form an anode. In contrast to the anode chamber, a cathode chamber was formed via a non-woven fabric of 30μm thickness. The cathode chamber was also 7cm×25cm×2cm (thickness), and two sheets of 10mm thick graphite felt were overlapped to form a cathode. On the graphite felts of the anode and cathode, stainless steel wires were bonded with conductive paste as electrical lead wires, and connected with a resistance of 5Ω.

[0071] The anode chamber is fed with an anode solution containing 1000 mg / L acetic acid, 50 mM phosphate buffer and ammonium chloride, the pH of which is maintained at 7.5. The raw water is preheated to 35°C in another water tank and then fed to the anode chamber at 70 mL / min, thereby heating the temperature of the anode chamber to 35°C. Before the anode solution is fed, the outflow of another microbial power generation device is fed to the anode chamber as a bacterial culture. A cathode solution containing 50 mM potassium ferrocyanide and phosphate buffer is supplied to the cathode chamber at a flow rate of 70 mL / min.

[0072] The power generation reached 300W / m in one week after water flow started. 3 - Anode chamber volume, 280W / m for the next 3 weeks 3 ~330W / m 3 After a week, it dropped to 100W / m 3 The acetic acid concentration in the treated water was almost unchanged. On the other hand, the current efficiency was 3 ~330W / m 3 The change period was 60% to 80%, and decreased to 10% to 20% as the power generation decreased. Therefore, it is considered that the methane-producing bacteria became dominant in the anode chamber about one month after the water flow started.

[0073] [Example 1]

[0074] The same as in Comparative Example 1, 28 days after the start of water flow, at 280 W / m 3 ~330W / m 3 The power generation capacity is less than 250W / m 3 After 2 hours of aeration at a flow rate of 300 mL / min, the power generation recovered to 300 W / m 3 When the power generation decreased again, the anode chamber was aerated with air as before and recovered, and then maintained at 300W / m for 1 week. 3 During this period, the current efficiency ranged from 50% to 70%.

[0075] [Example 2]

[0076] The structure is the same as that of Comparative Example 1. After one week from the start of water flow, the power generation reaches 300W / m 3 The anode chamber was aerated with air at a flow rate of 300 mL / min once a day for 10 minutes.

[0077] The power generation in the next 3 months is 300W / m 3 ~320W / m 3 , the current efficiency is stable at around 70%.

[0078] According to the above comparative examples and working examples, it was confirmed that the present invention can suppress the growth of methanogens in the anode chamber of the microbial power generation device, thereby stably obtaining high power generation for a long period of time.

[0079] Although the present invention has been described in detail using specific embodiments, it will be apparent to one skilled in the art that various modifications can be made without departing from the spirit and scope of the present invention.

[0080] This application is based on Japanese Patent Application No. 2018-055812 filed on March 23, 2018, the entire contents of which are incorporated herein by reference.

[0081] Description of Reference Numerals

[0082] 1, 30: tank body;

[0083] 2, 31: separation material;

[0084] 3, 33: cathode chamber;

[0085] 4, 32: anode chamber;

[0086] 5, 35: cathode;

[0087] 6, 34: anode;

[0088] 7, 17, 51, 57: air diffuser.

Claims

1. A microbial power generation device, comprising: an anode chamber having an anode and holding a liquid containing microorganisms and an electron donor, and a cathode chamber separated from the anode chamber by a porous non-conductive membrane, The anode chamber is supplied with raw water containing organic matter, and the cathode chamber is supplied with a fluid containing an electron acceptor to generate electricity. The microbial power generation device is characterized in that it includes: an oxygen supply unit for intermittently supplying oxygen into the anode chamber, Oxygen is supplied so that the dissolved oxygen concentration in the anode chamber becomes 2 mg / L to 8 mg / L.

2. The microbial power generation device according to claim 1, wherein: The oxygen supply unit is an aeration unit for an oxygen-containing gas.

3. The microbial power generation device according to claim 1, wherein: The oxygen supply unit is a unit for supplying oxygen-dissolved water.

4. A method for operating a microbial power generation device, the microbial power generation device comprising: an anode chamber having an anode and holding a liquid containing microorganisms and an electron donor, and a cathode chamber separated from the anode chamber by a porous non-conductive membrane, The anode chamber is supplied with raw water containing organic matter, and the cathode chamber is supplied with a fluid containing an electron acceptor to generate electricity. The method for operating the microbial power generation device is characterized in that: intermittently supplying oxygen into the anode chamber, Oxygen is supplied so that the dissolved oxygen concentration in the anode chamber becomes 2 mg / L to 8 mg / L.

5. The method for operating the microbial power generation device according to claim 4, wherein: The oxygen-containing gas is supplied to the anode chamber at a frequency of once every 2 hours to 30 days for 30 seconds to 12 hours each time.

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