78 results about "Microbial electrolysis cell" patented technology

A method for producing product gas (PG) comprising methane is disclosed, the method comprising the steps of providing a biomass (BM), subjecting the biomass (BM) to an anaerobic digestion to produce biogas (BG) and a biomass digestate (BMD), separating the biomass digestate (BMD) into a liquid digestate fraction (LDF) and a solid digestate fraction (SDF), and subjecting the liquid digestate fraction to microbial electrolysis cell (MEC) processing to produce methane and / or hydrogen gas. Also, a system for producing product gas (PG) comprising methane is disclosed.

The invention relates to a system for producing methane through biogas reflux coupling microbial electrolysis cell (MEC) enhanced anaerobic digestion and application. A reactor system comprises an MEC anaerobic digestion system and a biogas reflux system. The MEC anaerobic digestion system is provided with a biological anode plate and a biological cathode plate, electroactive microorganisms attached to the biological anode plate convert organic matters into carbon dioxide and generate electrons, and electroactive microorganisms attached to the biological cathode plate convert carbon dioxide into methane; a secondary biogas separation tank is adopted for biogas separation in the biogas backflow system, carbon dioxide in the biogas is more effectively separated out, and the carbon dioxide intermittently flows back to a biological cathode plate of the MEC anaerobic digestion system after being collected. Compared with the prior art, the anaerobic digestion treatment of the organic solid waste is realized, and the in-situ upgrading of the biogas is also realized; and the separated carbon dioxide reflux can be efficiently methanated, so that the emission of the carbon dioxide is reduced, the in-situ treatment of the carbon dioxide is realized, the intermediate links are reduced, and the cost is reduced.

The invention discloses a three-stage coupling continuous enhanced hydrogen production method. The method comprises the following steps: step 1, preparing an oxygen-free environment; step 2, enrichment and propagation of hydrogenogens; step 3, enrichment and propagation of photosynthetic bacteria; step 4, performing enzymolysis saccharification on the kitchen garbage; 5, carrying out anaerobic dark fermentation to produce hydrogen; step 6, carrying out anaerobic light fermentation to produce hydrogen; and 7, continuously culturing to produce hydrogen. According to the continuous culture principle, hydrogen is continuously and efficiently produced through the dark fermentation tank, the light fermentation tank and the microbial electrolysis cell at the same time, and the method has the advantages of low cost, short fermentation time, complete process and high yield. And when the hydrogen production rate of dark fermentation begins to decrease, the substrate is continuously circulated, and the volatile organic acid generated by terminal metabolism of dark fermentation is consumed by light fermentation, so that the feedback inhibition effect of the volatile organic acid on hydrogenogens is effectively solved. The utilization range of the substrate of the microbial electrolysis cell is wide, thorough oxidation of residual organic matters is realized under the assistance of electricity-producing microorganisms, and the problem of incomplete dark-light coupling anaerobic fermentation can be effectively solved.

The invention relates to the technical field of microbial electrochemistry, in particular to a microbial fuel cell self-driven microbial electrolysis cell system and application thereof. The microbial fuel cell self-driven microbial electrolysis cell system comprises a microbial electrolysis cell (MEC) and a microbial fuel cell (MFC) for supplying power to the MEC; an anode electrode of the MFC is a mixed strain immobilized modified carbon felt electrode, and a cathode electrode of the MFC is a modified carbon felt electrode; an anode electrode and a cathode electrode of the MEC are independently selected from one of a modified carbon felt electrode or a mixed strain immobilized modified carbon felt electrode; the mixed strain is a strain obtained by mixing shewanella and sludge bacteria; the anode electrode of the MEC is connected with the cathode electrode of the MFC, and the anode electrode of the MFC is connected with the cathode electrode of the MEC; the bipolar chambers of the MFC are both in an anaerobic state, and the bipolar chambers of the MEC are both in an anoxic state. The advantages of an MFC-MEC system are fully utilized, external power supply is not needed, the MFC supplies energy to the MEC to promote reverse flow of electrons, and electric energy is utilized in situ.

The invention provides a kitchen garbage biomass energy resource cascade recovery system, which comprises a pretreatment unit, a biomass energy resource cascade recovery unit, a biomass energy resource cascade recovery unit and a biomass energy resource cascade recovery unit, and is characterized in that the pretreatment unit is used for pretreating kitchen garbage and straws to obtain slurry and solids; the solid phase treatment unit comprises a biological hydrolysis device, a biological fermentation device and a biological decomposition device which are connected in sequence; the biological hydrolysis device is connected with the pretreatment unit; the product utilization unit is connected with the biological decomposition device; the liquid phase treatment unit comprises a dark fermentation hydrogen production device, a microbial electrolysis cell hydrogen production device and an anaerobic digestion methane production device which are connected in sequence; the dark fermentation hydrogen production device is connected with the pretreatment unit; and the tail water utilization unit is connected with the anaerobic digestion methane production device. The gas, the liquid and the solid generated by the recovery system are subjected to effective energy recovery and maximum resource utilization, no three wastes are generated, and the recovery system can be widely applied to the fields of agriculture, environmental protection, energy and the like.

To provide a novel microorganism having higher current generating ability, a microbial fuel cell composition and microbial electrolysis cell composition comprising the microorganism, as well as a microbial electrolysis cell and microbial electrolysis cell using the microorganism.SOLUTION: Provided are: a microorganism, a Geobacter sp. strain 60473; a microbial fuel cell composition comprising the Geobacter sp. strain 60473 and an organic substance; a microbial fuel cell in which the Geobacter sp. strain 60473 is used to decompose the organic substance as a fuel; a microbial electrolysis cell composition comprising the Geobacter sp. strain 60473 and the organic substance; and a microbial electrolysis cell in which the Geobacter sp. strain 60473 is used to decompose the organic substance as the fuel.SELECTED DRAWING: None

The invention discloses a system for improving pollution reduction and carbon reduction of a constructed wetland-microbial electrolysis cell by adding fulvic acid and an operation method thereof, and belongs to the field of ecological environment governance, the system comprises a water inlet system, a purification system, a water outlet system, an adder and an intelligent detection system; the purification system comprises more than one purification unit, and different connection relations are constructed through opening and closing of valves; wastewater input from the water inlet system is discharged from the water outlet system after reaching the standard through the adsorption-electrolysis purification effect of the purification system, the intelligent detection system dynamically judges whether fulvic acid needs to be added or not and the adding amount according to the water quality condition of inlet water, meanwhile, the operation mode is accurately adjusted, the treatment effect is remarkably improved, and carbon emission is remarkably reduced. The method has the advantages of being good in treatment effect, stable in operation, convenient to operate and run and the like, particularly realizes precise dynamic addition according to different working conditions to improve the pollution and carbon reduction effect of the constructed wetland, and has the advantages of high intelligence, low carbon and greenness.

A wastewater stream is flowed from a separator to an anode side of a microbial electrolysis cell (MEC). The wastewater stream includes water and hydrocarbons. The separator is positioned in a gas-oil separation plant. The MEC electrolyzes the hydrocarbons to produce hydrogen ions. A membrane separates the MEC into the anode side and a cathode side. The membrane allows the hydrogen ions and water molecules to pass through the membrane from the anode side to the cathode side, thereby forming a treated wastewater stream at the cathode side. The MEC combines the hydrogen ions at the cathode side to produce hydrogen gas. The treated wastewater stream and a hydrogen gas stream is discharged from the cathode side. The hydrogen gas stream includes the hydrogen gas produced by the MEC. The hydrogen gas stream is oxidized into water. Electrical power is generated in response to oxidizing the hydrogen gas into water.

The invention discloses a CSTR-based three-dimensional electrode MEC-fluidized bed reactor for anaerobic fermentation of cow dung and application, and belongs to the technical field of microbial electrochemistry. The reactor comprises a reactor main body, a feed port, a discharge port, a gas outlet and a stirring device, an anode and a cathode are arranged in the reactor main body, a conductive three-dimensional particle electrode filler is filled between the anode and the cathode to form a three-dimensional electrode system, and the anode and the cathode are connected with an external power supply. The three-dimensional electrode system is constructed, so that the reaction specific surface area and the electron transfer efficiency are greatly increased, the stimulation effect of a low-voltage electric field is amplified to the whole reaction space, and the technical bottlenecks of low mass transfer efficiency, low methane yield, easiness in system instability and the like in the traditional cow dung anaerobic digestion are solved. Compared with the traditional anaerobic digestion and two-dimensional microbial electrolysis cell, the two-dimensional microbial electrolysis cell disclosed by the invention can obviously improve the methane yield and the system operation stability, and has an excellent engineering application prospect.

The application discloses application of microbial electrochemical coupling anaerobic reaction reinforced biological methane synthesis in carbon neutralization. A microbial electrolysis cell is composed of an anode chamber, a cathode chamber and a proton exchange membrane, the anode chamber and the cathode chamber are connected through the proton exchange membrane, a mixed solution of sewage, ionic liquid and a solution of first methanogenic microorganisms is used as a substrate in the anode chamber, a mixed solution of culture medium, ionic liquid and a solution of second methanogenic microorganisms is used as a substrate in the cathode chamber, under the action of an external power source, the sewage in the anode chamber is degraded to generate electrons and H + , H + CO2 in the cathode chamber is converted into methane under the action of microorganisms; the first ionic liquid or the second ionic liquid is an amino acid anion type ionic liquid. The microbial electrolysis cell is convenient to operate and maintain and has a small floor area.

This invention discloses an anaerobic bio-fermentation process for the targeted degradation of municipal sewage sludge, belonging to the field of sludge treatment technology. The process includes: pretreatment and targeted activation of components; staged hydrolysis and acidification for targeted production of short-chain fatty acids; methanogenic fermentation mediated by conductive materials coupled with a microbial electrolysis cell for assistance; multi-parameter dynamic control based on online monitoring and intelligent algorithms; magnetic separation, recovery, and recycling of magnetic conductive materials; in-situ biogas purification and product gradient reflux; solid-liquid separation and residue resource utilization. This invention achieves kinetic matching and metabolic enhancement of hydrolysis and acidification and methanogenesis through the deep linkage of four modules: targeted hydrolysis and acidification, enhanced direct interspecies electron transfer via a microbial electrolysis cell, magnetic material circulation, and intelligent control. Compared with existing technologies, the methane yield is increased by more than 40%, propionic acid accumulation is below 50 mg / L, the fermentation cycle is shortened to 8-10 days, and system energy consumption is reduced by 20%.

The present invention refers to a method to produce methane or at least one other synthesis product by methanogenic microorganisms in a microbial electrolysis cell (MEC), while applying a separated nutrient feeding supply in a discrete or a continuous manner.

The invention discloses application of microbial electrochemical coupling anaerobic reaction enhanced biological methane synthesis in carbon neutralization. A microbial electrolysis cell is composed of an anode chamber, a cathode chamber and a proton exchange membrane, the anode chamber and the cathode chamber are connected through the proton exchange membrane, and a mixed solution of sewage, ionic liquid and a first methanogenic microbial solution serves as a substrate in the anode chamber. In the cathode chamber, a mixed solution of a culture medium, an ionic liquid and a second methanogenic microorganism solution serves as a substrate, under the action of an external power supply, sewage is degraded in the anode chamber to generate electrons and H < + >, the H < + > enters the cathode chamber through a proton exchange membrane, and CO2 is converted into methane under the action of microorganisms in the cathode chamber; the first ionic liquid or the second ionic liquid is amino acid anionic ionic liquid. The microbial electrolysis cell provided by the invention is convenient to operate and maintain and small in occupied area.

The application discloses a BOD real-time online monitoring device and relates to the technical field of water quality monitoring.The device comprises two monitoring units, each of which comprises a water inlet pump, a biological reactor and a water outlet pump which are sequentially connected through pipelines; the biological reactor is a microbial electrolysis cell; the biological reactor comprises a closed shell, a cylindrical cathode and an anode which is arranged in the cathode are arranged in the shell, and an electroactive biofilm is grown on the anode; the water inlet pump is communicated with a water inlet of the shell, and the water outlet pump is communicated with a water outlet of the shell; a data acquisition module is electrically connected with the cathode and the anode; a data processing module is electrically connected with the data acquisition module; a display screen is electrically connected with the data processing module; and a power supply is used for supplying power to the cathode, the anode, the data acquisition module and the display screen. The application realizes real-time online monitoring of BOD.

The invention relates to a liquid electrode suitable for amplification of a microbial electrolysis cell and a carbon sequestration device of the liquid electrode, and belongs to the field of microbial electrochemical application. The liquid electrode is composed of a solid electrode and humic acid dissolved in a reaction system. As an electron shuttle and a pseudocapacitance energy storage medium, humic acid can efficiently receive electrons from a solid-state electrode and uniformly transmit the electrons to microorganisms in a dissolved state at a long distance in the space of the reactor; therefore, the scale effect problem that the electron transfer efficiency is reduced due to the fact that the size of the microbial electrolysis cell is increased, the electrode distance is increased and the electrode area per unit volume is reduced is fundamentally solved. The carbon sequestration device constructed on the basis of the liquid electrode integrates an autogenous dynamic membrane component taking a stainless steel mesh as a base material and a reverse osmosis product recovery system. The dynamic membrane can effectively intercept humic acid and microorganisms, selectively discharge small molecular products and relieve product inhibition; and the reverse osmosis system realizes high-efficiency recovery and process closed loop of products, and achieves zero emission.

The application discloses a temperature compensation type electrode pluggable microbial electrolysis cell water quality sensing device, which comprises a microbial electrolysis cell, a temperature sensor, an electrochemical workstation and an upper computer. The microbial electrolysis cell adopts a three-electrode system, the electrochemical workstation is used for collecting original current signals related to water quality output by the microbial electrolysis cell and transmitting original electric signal data to the upper computer. The temperature sensor is used for detecting the temperature of a solution in a working electrode area and transmitting a temperature analog signal to a temperature acquisition card for conversion, and transmitting converted digital signals to the upper computer. The upper computer establishes a temperature compensation model based on the characteristics of electrochemical microorganisms, calculates current signals after temperature compensation according to original current signals and measured temperature data, and judges water quality conditions according to the current signals after compensation.

The present disclosure provides a sewage treatment system and method for achieving nitrification based on a microbial electrolysis cell, the sewage treatment system including a microbial electrolysis cell; a constant voltage power supply, providing a constant voltage for the microbial electrolyte; an anaerobic ammonium oxidation reactor, connected to the water outlet of the microbial electrolysis cell, for performing an anaerobic ammonium oxidation reaction; wherein an anode and a cathode are provided in the microbial electrolysis cell, respectively connected to the positive and negative poles of the constant voltage power supply; an anode water inlet and a cathode water inlet are provided at corresponding positions of the anode and the cathode in the microbial electrolysis cell; the anaerobic ammonium oxidation reactor is provided with a bottom water inlet, an upper reflux port and a top water outlet. The sewage treatment system provided by the present disclosure has a high degree of integration, reduces the floor space, and has a low operating cost. The combined treatment of the microbial electrolysis cell and the anaerobic ammonium oxidation reactor effectively solves the problem of insufficient carbon source in the denitrification of low carbon-nitrogen ratio sewage.

The present application belongs to the cross field of bioelectrochemistry, environment and energy, and particularly relates to a microbial electrolysis cell amplification device integrating sewage treatment and carbon dioxide reduction to acetic acid; the amplification device is composed of a series connection of microbial electrolysis cell small test devices, and electrically active acetic acid-producing bacteria and electric bacteria loaded with high-conductivity nanomaterials and magnetic nanomaterials are respectively modified on the surface of cathode and anode electrodes; the anode electric microorganism decomposes and metabolizes organic matters in sewage to realize sewage treatment; the cathode acetic acid-producing bacteria capture CO2, catalyze CO2, H + and electron into acetic acid to realize carbon dioxide reduction to acetic acid; the microbial electrolysis cell amplification device has simple preparation method, high structural stability, low cost and low energy consumption, can simultaneously realize large-scale sewage treatment and CO2 reduction, provides a new way for domestic sewage and carbon dioxide resource utilization, and has important significance for energy saving and emission reduction and environmental governance.

The invention discloses a hydrogen production method for treating etching solution wastewater by using a photo-assisted single-chamber microbial electrolytic cell, and relates to the technical field of microbial electrochemistry and photocatalysis, and the hydrogen production method comprises the following steps: S1, mixing an anolyte of a stably operated double-chamber microbial fuel cell with etching solution tail end wastewater, adding the mixture into a reactor, and regularly replacing the solution until the anode potential is stable; s2, domesticating two ends of the electrode by using a direct-current power supply and external voltage until the potential of the cathode is reduced, and completing the domestication of the anode; and S3, the photocathode adopts a photocatalytic material, and organic matters are mineralized and nickel ions are removed while hydrogen is produced under an external voltage condition. The photo-assisted microbial electrolytic tank integrates the advantages of water electrolysis hydrogen production, photocatalytic hydrogen production and microbial electrolytic tank hydrogen production, overcomes the defect that a photocatalyst for photocatalytic hydrogen production is unstable, reduces the energy consumption required by microbial electrolytic tank hydrogen production, and recovers heavy metal mineralized refractory organics in etching liquid tail end wastewater. The method is a clean, efficient and low-consumption mode for treating wastewater and simultaneously producing hydrogen.

The present invention provides a microbial electrolysis cell and a method for treating uranium-containing wastewater. The microbial electrolysis cell comprises an electrolysis cell; an electrolyte solution and uranium-containing wastewater are disposed within the electrolysis cell; a bioanode and a biocathode disposed within the electrolysis cell; and an external circuit connecting the bioanode and the biocathode. The microbial electrolysis cell is used to perform microbial electrochemical reduction of the uranium-containing wastewater. Compared with existing technologies, the present invention utilizes a microbial electrolysis cell to treat uranium-containing wastewater. This cell can reduce hexavalent uranium ions to a relatively low concentration by applying a relatively low external voltage, and has a wide pH range of applicability. Furthermore, the establishment of a biocathode accelerates the treatment of uranium-containing wastewater, improves treatment efficiency, and reduces operating costs. Furthermore, the microbial electrolysis cell can produce a large amount of hydrogen while treating the uranium-containing wastewater.

The invention discloses a method for degrading toluene in a microbial electrolytic cell, comprising the following steps: 1) using low-cost pulp as raw material, preparing a cellulose carbon aerogel / polypyrrole composite material (CA-ppy) by a sol-gel method and conductive polymer loading; 2) using the CA-ppy composite electrode material as a bioanode, constructing a packed bed microbial electrolytic cell for degrading toluene; 3) taming and starting the bioanode, forming an anode biofilm on the anode electrode, and taming electroactive microorganisms capable of degrading toluene; 4) investigating the performance of the microbial electrolytic cell in treating toluene under different potentials and residence times, and determining optimal operating parameters.

The invention discloses a method and a device for rapid enrichment culture of salt-tolerant electroactive HNAD target bacteria, and aims to solve the problems of low enrichment efficiency, long screening period and difficulty in pure bacteria separation of salt-tolerant HNAD florae in the prior art. The method is used for rapidly enriching and separating the salt-tolerant electroactive HNAD strain, so that the denitrification performance and the application potential of the strain in a high-salt environment are improved.

The invention discloses a modification method of a stainless steel mesh cathode and application of the stainless steel mesh cathode in sewage phosphorus recovery of a microbial electrolysis cell, and belongs to the field of sewage phosphorus recovery. The modification method of the stainless steel mesh cathode comprises the following steps: preparing a Ni-Co-Sn modified stainless steel mesh cathode by taking a stainless steel mesh as a cathode and adopting an electro-deposition method; electrolyte used in the electrodeposition method comprises sodium citrate, nickel sulfate, cobalt sulfate, stannous mono-sulphate, boric acid and sodium chloride. According to the method, the stainless steel mesh which is cheap and more beneficial to struvite crystal attachment is selected as the cathode, the stainless steel mesh cathode is modified through nickel, cobalt and tin, the phosphorus recovery rate is increased by improving the hydrogen evolution performance of the stainless steel mesh cathode, the reaction time is shortened, and the purpose of obtaining the high phosphorus recovery rate within a short time is achieved.

Disclosed are a microbial electrolysis cell suppressing methane generation and a method of producing hydrogen using the same, and more particularly microbial electrolysis cell technology, which prevents the growth of methanogens inside a reactor during operation of a microbial electrolysis cell by aerating a substrate for use in a microbial electrolysis cell with acetylene gas before supply of the substrate, thereby suppressing consumption of the hydrogen and substrate by methanogens, ultimately increasing the hydrogen yield and lifespan of the microbial electrolysis cell.

The invention discloses a microbial electrolysis cell device and method for purifying phosphorus pollution by utilizing agricultural waste biochar. The device comprises an electrolytic tank main body (1) and a circulating system. The electrolytic tank main body (1) is of a single-chamber structure, and the constant-voltage power supply (12) is connected with the anode bar (2) and the cathode bar (3). And the cathode bar (3) adopts a composite structure of a permeable electrode shell (31) and a biochar electrode (32), so that the electrode is convenient to replace and recycle. The device can be further provided with a monitoring system and a reaction maintaining system, and automatic regulation and control are achieved. The method comprises the steps of microbial inoculation and biofilm formation, pretreatment feeding, calcium source supplementation, electrolytic adsorption coupling phosphorus removal, calcium phosphate recovery and the like, and efficient phosphorus removal and phosphorus resource recovery are achieved through the synergistic effect of electrochemistry and biological adsorption under the condition of low voltage (0.5-1.5 V). The method is suitable for treating multi-source phosphorus-containing wastewater in agriculture, industry, life and the like.

The invention relates to the technical field of anaerobic digestion of crop straw raw materials, and particularly discloses a method for strengthening anaerobic methanation of crop straw based on biological micro-aerobic pretreatment combined with a microbial electrolysis cell. According to the method, crop straw is placed in a closed system added with calcium peroxide (CaO2) and inoculated sludge for biological micro-aerobic pretreatment. A micro-aerobic environment created by CaO2 is utilized to stimulate facultative hydrolytic bacteria to enrich and secrete a large amount of hydrolase, and the lignocellulose structure of the straw is efficiently cracked. After pretreatment, the system is transferred into a microbial electrolysis cell reactor, inhibition of residual oxidizing substances in pretreatment on methanogenic archaea is effectively eliminated by utilizing a cathode reduction effect, and meanwhile, electron transfer and methanogenic metabolism paths of the system are enhanced. Through a coupling strategy of'biological micro-aerobic pretreatment + microbial electrolysis cell ', synergistic improvement of hydrolysis and methanation processes is realized, and an innovative and feasible solution is provided for efficient anaerobic digestion of crop straws to produce methane.

The invention relates to the technical field of microbial electrolysis cell cathode preparation, and particularly discloses a nickel-based cathode capable of enhancing hydrogen production of a microbial electrolysis cell and a preparation method of the nickel-based cathode. The method comprises the following steps: adding nickel nitrate hexahydrate into water, and mixing to obtain a nickel nitrate solution; adding urea into the nickel nitrate solution, and stirring until the urea is dissolved to obtain a first mixed solution; and foamed nickel is pretreated and then added into the first mixed solution to be subjected to a heating reaction, the foamed nickel is taken out to be calcined after the heating reaction is finished, and then the nickel-based cathode capable of enhancing hydrogen production of the microbial electrolysis cell is obtained through post-treatment. The foamed nickel is used as a carrier, the urea is used as a precipitator, the nickel nitrate hexahydrate is used as a nickel source, and the nickel base is loaded on the surface of the foamed nickel, so that the overpotential of the hydrogen evolution reaction is further reduced, and the hydrogen evolution efficiency of the microbial electrolytic tank is greatly improved.

The invention discloses a preparation method of a zirconium-based metal organic framework loaded cobalt-aluminum layered double hydroxide with oxygen reduction, hydrogen evolution and oxygen evolution performances, and the preparation method comprises the following steps: taking a hexagonal cobalt-aluminum layered double hydroxide as a substrate, and fusing an octahedral zirconium metal organic framework to form a unique layered framework heterostructure. The structure is beneficial to enhancing the electrochemical performance and promoting the interaction between the electron active materials. Meanwhile, obvious hexagonal cobalt-aluminum layered double hydroxides exist on the surface of the zirconium-based metal organic framework loaded cobalt-aluminum layered double hydroxides. The observation result proves that the cobalt-aluminum layered double hydroxide is successfully deposited on the zirconium metal organic framework, and the formation of the zirconium-based metal organic framework loaded cobalt-aluminum layered double hydroxide is verified. As a three-function catalyst with efficient catalytic performance in oxygen reduction, hydrogen evolution and oxygen evolution reaction, the material fully shows excellent catalytic performance in practical application of microbial fuel cells and microbial electrolytic cells. The unique structure provides abundant active sites, and the electron transfer rate is obviously enhanced, so that the overpotential of the microbial electrolysis cell is effectively reduced, and the overall energy efficiency and operation stability of the system are improved. The invention provides a key material solution for developing a high-performance and low-cost bioelectrochemical system, and has important significance for promoting the development of a green energy technology and an environment restoration technology.

The invention aims to provide a pretreatment device for synchronously and intensively preparing biodiesel by utilizing microalgae to generate electricity, and belongs to the field of biomass energy production. The invention belongs to a microbial electrochemical coupling system, and adopts a microbial fuel cell (MFC) and a microbial electrolytic cell (MEC) as main structures. Anode microorganisms in the microbial fuel cell MFC take microalgae as a substrate, generate electricity through metabolism, and synchronously transmit electric energy to the microbial electrolytic cell MEC through a series lead to serve as an external power supply of the microbial electrolytic cell MEC; during continuous operation, algae liquid is fed into the MEC under the rate control of the pump, the MEC realizes microalgae wall breaking pretreatment through electric fermentation, and grease extraction is enhanced. According to the invention, the dependence of the traditional MEC process on external energy is broken through, the self-production and self-use of the capacity of the device are realized, the manual requirement for replacing the anolyte can be effectively reduced, and the microalgae biodiesel preparation pretreatment under continuous operation is realized.

The invention discloses a microbial electrolysis cell of a graphene electrode and a riverway in-situ remediation method of the microbial electrolysis cell, and belongs to the technical field of biological electrolysis cells. The microbial electrolysis cell is provided with a graphene-coated bimetallic oxide array electrode, a titanium mesh is used as an electrode substrate, an electro-catalytic material is Graphene-coated NiO / ZnO, and the surface of the electrode is of a three-dimensional space structure. The microbial electrolysis cell is applied to in-situ remediation of a water body in a riverway. When the microbial electrolysis cell is used for repairing the river water body, the microbial electrode is beneficial to rapid formation of a biological membrane, and a large number of microorganisms are accumulated on the surface of the electrode in the wastewater treatment process; meanwhile, the graphene and bimetallic coupling electrode reduces the overpotential required by oxidation reduction of pollutants in wastewater. The metabolism of the electroactive microorganisms on the surface of the electrode is promoted by a proper external power supply, so that the overall efficiency of the microbial electrode disclosed by the invention is greatly improved.