LU502179B1 - Modular self-assembly microbial fuel cell - Google Patents

Abstract

A modular self-assembly microbial fuel cell formed by connecting a plurality of identical square cell units in series, each cell unit comprises an anode chamber and a cathode chamber separated along the diagonal of the battery cell with a proton exchange membrane is arranged in between. The anode chambers and cathode chambers of two adjacent battery cells are connected, and a proton exchange membrane is arranged between them. The invention nests and melts the multi-stage MFC anode chamber and the cathode chamber with each other, and realizes the maximum reduction of the internal resistance of the system. The single-stage MFC forms bidirectional intercommunication and transmission of protons with each other, the cross section of the transmission channel of protons between the anode chamber and the cathode chamber is greatly expanded, the proton transmission efficiency can be obviously improved.

Description

Description Modular self-assembly microbial fuel cell

TECHNICAL FIELD The application belongs to the technical field of waste water resource utilization and new energy resources development, and in particular to a modular self-assembly microbial fuel cell.

BACKGROUND In recent years, Microbial Fuel Cell (MFC) has been widely concerned by researchers at home and abroad, and laboratory-scale research results emerge in endlessly. The wastewater contains rich organic matter, which is removed purposefully as the target pollutant in the water treatment project. However, a large amount of organic matters contained in the wastewater can be completely supplied to the electricity-generating microorganisms as the biomass raw material of MFC. The electricity-generating microorganisms convert chemical energy into electrical energy through metabolism and can output through external circuits, thus realizing the double benefits of wastewater treatment and electrical energy production.

The microbial fuel cell is calculated according to Nernst equation, and the voltage generated by the aerobic biological cathode microbial fuel cell is generally lower than 0.8V. However, due to the key factors such as internal resistance and materials of microbial fuel cells, the commonly generated open circuit voltage (OCV) is significantly reduced, and the output voltage value is only about half of the theoretical value. The output voltage of the system can be effectively improved by effectively coupling the microbial fuel cells and constructing the microbial fuel cell stack.

At present, researches on modular self-assembly microbial fuel cells have not been reported, and no researchers have applied this new battery pack process to treat wastewater.

SUMMARY Aiming at defects of the prior art, designing the MFC battery pack as multi-stage series connection, and separating diagonally each unipolar cathode chamber from the 08178 anode chamber, which solves the technical problems of low self-produced electric energy, incomplete wastewater treatment and the like of the traditional microbial fuel cell.

The specific contents of the application are as follows: A modular self-assembly microbial fuel cell is formed by connecting a plurality of identical square cell units in series, each cell unit comprises an anode chamber and a cathode chamber, the anode chamber and the cathode chamber are separated along the diagonal of the battery cell, a proton exchange channel is arranged between the anode chamber and the cathode chamber, and the proton exchange channel is a proton exchange membrane; the anode chambers and cathode chambers of two adjacent battery cells are connected, and a proton exchange channel is arranged between them, and the proton exchange channel is a proton exchange membrane.

The bottom surface of the cube cell is preferably a cube.

Further, the proton exchange membrane is a cation exchange membrane.

The two sides of the proton exchange channel are sealed by stainless steel plate frame or flange; a cation exchange membrane is embedded in the proton exchange channel port to realize the unilateral proton transfer from the anode chamber to the cathode chamber; the cation exchange membrane simultaneously block that diffusion of dissolved oxygen and anion in the cathode chamber to the anode chamber, and maintains the aerobic state of the cathode chamber and the anaerobic state of the anode chamber.

Further, the electrodes of the anode chamber are stainless steel spiral wires, and the electrodes of the anode chambers of a plurality of battery cells are connected with each other and coupled to form a battery pack anode. The exposed stainless steel spiral wire is connected with titanium wire outdoors, which leads directly to the data acquisition system.

Further, the anode chamber is filled with graphite particles and activated carbon conductive particles with a filling rate of 100%. The mixed filler of the graphite and the activated carbon is used as a biological anode and is used as an electrogenic microorganism film-forming filler at the same time, to maintain high biological 1008178 activity in the room; the top of the packing 1s tightly packed with a porous mesh to prevent outflow of the packing with the treatment medium. It should be noted that any porous conductive material may be used to fill the anode chamber.

Further, the electrodes of the cathode chambers are conductive substrate catalytic films, and the electrodes of the cathode chambers of a plurality of battery cells are connected with each other and coupled to form a battery pack cathode. The cathode electrode of the chamber is connected with the data collection system by titanium wire; the cathode chamber is also used as an electric membrane bioreactor, the conductive base membrane is pressed into a flat membrane module, the outlet of the membrane module is connected with a vacuum pressure gauge, and the transmembrane pressure difference of the membrane module is monitored in real time; the outlet flow rate of the membrane module is regulated by a negative pressure suction pump.

Further, an external resistance is provided between the electrode of the anode chamber and the electrode of the cathode chamber in the battery cell.

Further, the cathode chamber is internally provided with a dissolved oxygen supplementing aeration device. The aeration device can be aeration stone (bar/head/pipe), which is externally connected with an aeration pump, and the gas flow rate is adjusted by the aeration pump.

Further, the anode chamber and the cathode chamber of the battery cell are separated by a separator, namely a single-stage chamber separator; the top of the partition board is provide with a plurality of triangular slots; the top of the anode chamber is sealed by a gland and provided with exhaust holes and an exhaust valve; the top of the cathode chamber is open, and the upper part of the outer side wall is provided with an overflow port; Inoculate aerobic activated sludge in the cathode room, and open an emptying port at the lower part of the cathode chamber.

The clapboard is equal to the anode chamber in height, a plurality of triangular hole grooves are arranged at the liquid level at the top of the clapboard to form a triangular weir overflow outlet, and the outlet water of the anode realizes natural dissolved oxygen through the porous overflow weir to improve the dissolved oxygen 08178 concentration level of the water body. An overflow port at the upper part of the outdoor side wall of the cathode is connected with an overflow pipe, and overflow water flows back to the original water tank to prevent the water level from being too high when the cathode membrane treatment efficiency is insufficient, and the overflow water 1s led back to the original water tank at the same time to form a sewage closed cycle treatment. The emptying port at the bottom of the cathode chamber can be used as both a sludge discharge port and a microorganism sampling port; the cathode room is equipped with on-line dissolved oxygen (DO) and pH monitoring probes to monitor the DO and pH changes in real time.

Further, a water separator is arranged at that bottom of the anode chamber, and the water inlet mode is push flow from bottom to top. The water separator can be connected with an external water inlet L-shaped bent pipe, and the height of the water inlet L-shaped bent pipe is higher than the anode chamber. The water inlet mode can prevent oxygen from entering and effectively maintain the anaerobic environment of the anode chamber. The inlet flow rate of the anode chamber is controlled and regulated by a flow meter.

Further, the lower part of the outer side wall of the anode chamber is provided with an emptying port, the emptying port is connected with an emptying pipe and provided with an emptying valve, and the emptying port simultaneously serves as a microbial sample sampling port of the anode chamber.

Further, a reference electrode is inserted into the upper part of the anode chamber, and the reference electrode is connected with a data collection system.

The application also provides a microbial fuel cell stack structure, which consists of more than two integrated multistage microbial fuel cell stacks connected in parallel with each other. The battery pack provided by the application has various combination modes, can be connected in series or in parallel, has a compact structure and is suitable for water treatment engineering effluent requirements.

The application has the following beneficial effects: The application breaks through the structural design of the conventional microbial fuel cell, innovatively nests and melts the multi-stage MFC anode chamber 08178 and the cathode chamber with each other, obviously reduces the spacing between the anode chamber and the cathode chamber, greatly reduces the spacing between the cathode membrane and the proton exchange membrane, and realizes the maximum reduction of the internal resistance of the system. The single-stage MFC forms bidirectional intercommunication and transmission of protons with each other, the cross section of the transmission channel of protons between the anode chamber and the cathode chamber is greatly expanded, the proton transmission efficiency can be obviously improved, the electrochemical reaction rate at the electrode reaction interface is effectively improved, and the transmission efficiency of electrons between the two chambers is improved. The structure of that integrate multistage microbial fuel cell stack is self-contained, associated with each other and capable of produce mutual promotion.

The wastewater is subject to the integrated MFCU multistage continuous treatment, so that the multistage MFC continuous treatment of pollutant is realized, the biological degradation efficiency of organic matters is high, and difficult-to-degrade pollutants such as ammonia nitrogen, total phosphorus and the like are treat alternately through anaerobic and aerobic processes, so that the removal efficiency is synchronously improved.

The MFCU designed by the application can realize unit expansion and increase or decrease the single-stage MFC reaction module according to the original water pollution load and effluent requirement; in actual operation, not only series operation but also parallel operation can be realized, and the operation mode can realize convenient switch; at the same time, according to the needs of wastewater treatment functions, the modularization can be realized to increase the reaction stages and effectively increase or decrease the operation reaction process. The outstanding features of the MFCU modular multi-stage structure design are the significant reduction of the cell spacing, the significant shortening of the proton transfer channel, and the significant acceleration of the electrochemical reaction rate on the electrode surface.

The compact structure design of the battery pack, all the functional components 08178 adopt cheap materials, the operation is simple and convenient, and the engineering applicability is strong; the integrated multi-stage microbial fuel cell stack can realize continuous and high-efficiency treatment of wastewater, increase and decrease reaction modules according to system load and effluent water quality, has relatively strong anti-pollution load capacity, low wastewater treatment cost and can realize continuous and economic operation.

BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a frame diagram of a modular self-assembly microbial fuel cell system; FIG. 2 is a schematic diagram of proton channel structure; FIG. 3 is an electric energy output diagram of the modular self-assembly microbial fuel cell in the embodiment; FIG. 4 is a diagram of COD (chemical oxygen demand) treatment performance of modular self-assembly microbial fuel cell in the embodiment; in FIG. 1 and FIG. 2: 1. Anode chamber; 2. Cathode chamber; 3. Single-stage chamber partition; 4. Interstage plate; 5. Proton exchange channel; in FIG. 3, the abscissa represents time, unit d; the ordinate represents the voltage, unit v; the triangle, the square and the circle respectively represent the cell voltage, the anode potential and the cathode potential; in FIG. 4: The abscissa indicates time, unit D; the ordinate represents the influent concentration and removal efficiency, unit mg/L and %; square and dot respectively represent influent concentration and removal efficiency of COD.

DESCRIPTION OF THE APPLICATION The principles and features of the application will be described with reference to the following examples, which are only used to explain the application, but not to limit the scope of the application.

The three-stage reaction series of the battery pack is taken as an example, and the MFC reaction module can be flexibly increased or decreased according to engineering requirements in the application.

As shown in FIG. 1 and FIG. 2, the structural dimension of the cuboid integrated multistage microbial fuel cell stack is 60 cm x 20 cm x 50 cm (length x width x 1008178 height), the single-stage MFC has a capacity of 20 cm x 20 cm x 50 cm (length x width x height), there are three MFC levels in the battery pack, namely three single cells, a diagonal plate is divide in the single-stage MFC, two chambers are respectively used as a single-stage anode chamber and a cathode chamber, the double chambers have equal capacity, and each chamber accounts for 10 L; the bottom of the battery pack is provided with a chassis with a tray structure, which is convenient for transporting and disassembling, and the height of the anchor is 8 cm.

Single-stage anode chamber: The bottom surface of that single-stage anode chamber is an isosceles right-angle triangle, the length of the right-angle side is 20 cm, the height of the chamber is 50 cm, and the out plate of the right-angle side is protected from light by using shading pap; a water separator is arranged in the center of the anode chamber, the diameter of the main water diversion pipe is 15 cm, the diameter of the branch water diversion pipe is 10 cm, and the outlet aperture of the branch water diversion pipe is 2 cm; the water separator is provided with that bottom of a pipe support fix chamber, a main pipe is connected with the bottom by an external thread, the exposed bottom of the external thread of the water dividing main pipe is 4 cm, an |-shaped bent pipe is led from the outside of the bottom to the top of the chamber, the exposed top is 4 cm, and the bent pipe is fixed with the chamber wall by adhesive welding; the inlet flow of the anode chamber is controlled by a rotameter, and the inlet flow of the battery pack is a bottom push flow type; the lower part of the outdoor side wall of the anode is provided with an evacuation port, which is connected with an evacuation pipe, the diameter of which is 15 cm, and is externally connected with an evacuation valve, and the evacuation pipe is also used as a microbial sampling port in the anode chamber; a stainless steel spiral wire is inserted from the top of the anode chamber at the center of the anode chamber, the material is 316 L, the wire diameter is 2 cm, and the spiral radius is 5 cm, the stainless steel spiral wire is used as the anode of the MFC, the top of the anode wire chamber is exposed and connected with the titanium wire, and a data acquisition system is introduced; the anode chamber is filled with conductive particles of activated carbon and graphite, the particle size is 3-5 mm, the mixing volume ratio is 2:1, and the 1008178 filling rate is 100%. The mixed filler is used as MFC biological anode, and at the same time, it is used as the filler for biofilm formation of electricity-producing microorganisms. To prevent the outflow of graphite and activated carbon, the top of the packing layer is compacted and sealed with porous mesh, the mesh number of which is 8 meshes; a 232 calomel reference electrode is inserted below the top of the anode chamber filler, and an electrode line is connected with a data collection system; the anode of the three-stage MFC anode chamber is interconnected and coupled to form a battery pack anode; the gland at the top of the anode chamber is sealed with preset vent holes and vent valves, the diameter of the vent holes is 3 mm; the anode chamber and cathode chamber in the unipolar battery are separated by a single-stage chamber partition board, and a plurality of triangular slots are preset at the liquid level at the top of the partition board. The slot holes are equilateral triangles, with a side length of 4 mm and a triangular slot spacing of 1 cm. The anode chamber is designed as a triangular weir to discharge water, and the anode outlet water will naturally dissolve oxygen after flowing through the weir.

Single-stage cathode chamber: the bottom of the single-stage cathode chamber is an isosceles right triangle, with a right-angled side length of 20 cm, a total chamber height of 50 cm, and an effective medium level control height of 30 cm; the single-stage cathode chamber is adjacent to the double anode chamber; An aerator is arranged at the center of the cathode chamber, the diameter of the aerator is 10 cm, an aeration oxygen-increasing pump is externally arranged, and the aeration amount is controlled by a gas flow meter; the carbon fiber-based conductive catalytic membrane module in the cathode chamber serves as a single-stage MFC cathode electrode and simultaneously serves as a filtering unit of an electromembrane bioreactor; the membrane component is externally connected with a titanium wire and is connected with a data acquisition system, and an external resistor is additionally arranged between a unipolar MFC internal anode and a membrane cathode; the cathode of that multi-stage MFC conductive film are connected with each other to form the cathode of the battery pack; the membrane component is used for pumping out water by a negative pressure pump, a vacuum pressure gauge monitors that transmembrane 08178 pressure difference in real time, and a water outlet flow meter control the water yield; the cathode chamber is inoculated with aerobic activated sludge with a sludge concentration of 4 g/L; the lower part of the cathode chamber is additionally provided with an emptying port which serves as a sludge discharge port and a microbial sampling port of the cathode chamber; the upper part of the outdoor side wall of the cathode is provided with an overflow port, which is connected with an overflow pipe, the diameter of which is 12 (mm), and the overflow pipe leads directly to the original water tank; dissolved oxygen (DO) and pH value on-line monitoring probes are preset in the cathode chamber to monitor DO and pH value changes in real time.

Proton exchange channel: The clapboard between that single-stage MFC anode chamber and the cathode chamber are all provided with proton exchange channels, and the single-stage chamber clapboard between the single-stage MFC anode chamber and the cathode chamber is preset with the proton exchange channel size of 22 cm x 28 cm (length x height); the proton exchange channel uses a cation exchange membrane as an inter-chamber separator, and the cation exchange membrane is screwed tightly through a flange plate; Battery pack performance test: Inoculating electricity-producing microorganisms in the anode chamber; During the initial operation of the system, the flow rate of water into the battery pack is 2 L/h, which is continuously running for 10 days. After the anode potential stabilized, the flow rate of water was adjusted to 4 L/h; after 15 days of continuous operation, the battery pack performance is tested. The performance test results are shown in FIG. 3 and FIG. 4, which show that the system can stably generate electricity and efficiently treat wastewater.

The above is only a preferred embodiment of the present application, and it is not intended to limit the present application. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present application should be included in the scope of protection of the present application.

Claims (10)

Claims LU5021 79

1. A modular self-assembly microbial fuel cell, which is characterized by being formed by connecting a plurality of identical square cell units in series, each cell unit comprises an anode chamber and a cathode chamber, the anode chamber and the cathode chamber are separated along the diagonal of the battery cell, a proton exchange channel is arranged between the anode chamber and the cathode chamber, and the proton exchange channel is a proton exchange membrane; the anode chambers and cathode chambers of two adjacent battery cells are connected, and a proton exchange channel is arranged between them, and the proton exchange channel is a proton exchange membrane.

2. The modular self-assembly microbial fuel cell according to claim 1, which is characterized in that the proton exchange membrane is a cation exchange membrane.

3. The modular self-assembly microbial fuel cell according to claim 1, which is characterized in that the electrodes of the anode chamber are stainless steel spiral wires, and the electrodes of the anode chambers of a plurality of battery cells are connected with each other and coupled to form a battery pack anode.

4. The modular self-assembly microbial fuel cell according to claim 1, which is characterized in that the anode chamber is filled with graphite particles and activated carbon conductive particles.

5. The modular self-assembly microbial fuel cell according to claim 1, which is characterized in that the electrodes of the cathode chambers are conductive substrate catalytic films, and the electrodes of the cathode chambers of a plurality of battery cells are connected with each other and coupled to form a battery pack cathode.

6. The modular self-assembly microbial fuel cell according to claim 1, which is characterized in that an external resistance is provided between the electrode of the anode chamber and the electrode of the cathode chamber in the battery cell.

7. The modular self-assembly microbial fuel cell according to claim 1, which is characterized in that the cathode chamber is internally provided with a dissolved oxygen supplementing aeration device.

8. The modular self-assembly microbial fuel cell according to claim 1, which is characterized in that the anode chamber and the cathode chamber of the battery cell 08178 are separated by a separator, the top of the partition board is provide with a plurality of triangular slots; the top of the anode chamber is sealed by a gland and provided with exhaust holes and an exhaust valve; the top of the cathode chamber is open, and the upper part of the outer side wall is provided with an overflow port; inoculate aerobic activated sludge in the cathode room, and open an emptying port at the lower part of the cathode chamber.

9. The modular self-assembly microbial fuel cell according to claim 1, which is characterized in that a water separator is arranged at the bottom of the anode chamber, and the water inlet mode is push flow from bottom to top.

10. A microbial fuel cell stack structure, which consists of more than two integrated multistage microbial fuel cell stacks connected in parallel with each other.