A wastewater treatment method based on a vanadium-based energy storage medium-microbial fuel cell coupled energy storage system

Abstract

The application discloses a kind of based on vanadium-based energy storage medium-microbial fuel cell coupling's energy storage system's wastewater treatment method, it is related to the technical field of chemical wastewater treatment, including the following steps: preparation is carried out to vanadium-based energy storage medium part, preparation is carried out to microbial fuel cell part, coupling system's assembly, experimental operation, parameter adjustment and optimization and data analysis and result evaluation, vanadium-based energy storage medium-microbial battery coupling system structure design can be realized in the application wastewater purification and CO2 reduction two functions, due to the intrinsic safety of vanadium-based energy storage medium and long life, can store unstable low efficiency chemical energy, solve the inefficiency and instability problem of microbial fuel cell, and vanadium-based energy storage medium first as electrolytic cell cathode, end electrochemical reaction again as primary cell anode direct cycle use, electrode input cost is saved.This coupling system uses vanadium-based energy storage medium instead of oxygen evolution (OER) reaction, greatly improve energy efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chemical wastewater treatment, and in particular to a wastewater treatment method based on a vanadium-based energy storage medium-microbial fuel cell coupled energy storage system. BACKGROUND

[0002] Wastewater treatment process is an economic, reasonable, scientific and effective process method for municipal domestic sewage and industrial wastewater. Wastewater treatment is widely used in construction, agriculture, transportation, energy, petrochemical, environmental protection, urban landscape, medical treatment, catering and other fields. Common processes include oxidation method, MBR membrane-biological reactor method and microbial method. However, the above-mentioned process methods still have the following problems:

[0003] Among them, the conventional advanced oxidation method is widely used in wastewater treatment, but it has high cost, large consumption of oxidizing agent and serious waste of chemical energy. These problems lead to low energy efficiency and economic decline in the wastewater treatment process.

[0004] In addition, in the MBR membrane-biological reactor method, high concentration of mixed liquid suspended solids (MLSS) can easily cause membrane blockage, which requires frequent membrane cleaning and the use of a large amount of cleaning agent, which not only increases the operation cost, but also has a negative impact on the environment.

[0005] In addition, in the microbial method, the mismatch between the microbial electrolysis cell and the microbial fuel cell limits the CO2 reduction in the microbial electrolysis cell to an electrochemical reaction, and the reaction rate is slow. The microbial anode reaction in the microbial fuel cell is limited by microbial metabolism, and the reaction rate is also slow. The mismatch between the two limits the efficiency and stability of the wastewater resource recycling. SUMMARY

[0006] The present application aims to provide a wastewater treatment method based on a vanadium-based energy storage medium-microbial fuel cell coupled energy storage system to overcome the above-mentioned defects in the prior art.

[0007] A wastewater treatment method based on a vanadium-based energy storage medium-microbial fuel cell coupled energy storage system, comprising the following steps:

[0008] S1, corresponding preparation work is carried out on the vanadium-based energy storage medium part;

[0009] S1.1, prepare vanadium ion solution: prepare an appropriate amount of vanadium ion solution containing different oxidation states of V 2+ and V 3+ ;

[0010] S1.2, Preparation of anode and cathode: using good conductive material to prepare anode and cathode, and immerse them in anode and cathode electrolyte respectively, separate the cathode and anode by ion exchange membrane, the cathode is loaded with efficient carbon dioxide reduction catalyst, the CO2 reduction reaction generates formic acid, the anode is vanadium-based reversible redox electron pair, the oxidation reaction of vanadium energy storage medium occurs;

[0011] S1.3, Connection circuit: connect the anode and cathode through an external circuit to form a closed circuit;

[0012] S2, the corresponding preparation work of microbial fuel cell part;

[0013] S2.1, Preparation of anode and cathode: using good conductive material to prepare anode and cathode, and immerse them in anode and cathode electrolyte respectively, separate the cathode and anode by ion exchange membrane, the cathode is loaded with efficient carbon dioxide reduction catalyst, the CO2 reduction reaction generates formic acid, the anode is vanadium-based reversible redox electron pair, the oxidation reaction of vanadium energy storage medium occurs;

[0014] S2.2, Preparation of microbial suspension: collect microbial suspension from appropriate environment;

[0015] S2.3, Assembly of microbial fuel cell: install the anode and cathode in a sealed electrolytic cell, separate the cathode and anode by ion exchange membrane, and connect an external circuit, the organic pollutants in the anode wastewater undergo oxidation reaction to generate CO2, the cathode undergoes reduction reaction of vanadium energy storage medium;

[0016] S3, Assembly of coupling system: place vanadium-based energy storage medium and microbial fuel cell in the same system, so that they can share the same electrolytic cell, ensure appropriate link between the two systems, and ensure that vanadium-based reversible redox electron pair can be switched between microbial fuel cell and vanadium-based energy storage medium, so that electrons and ions can be transmitted between them;

[0017] S4, Experimental operation: through charge calculation, inject organic wastewater into microbial fuel cell for microbial metabolic reaction and convert chemical energy into electrical energy, at the same time, circulate vanadium ion solution in vanadium-based energy storage medium to store electrical energy between anode and cathode, monitor the electrochemical indicators of energy storage medium system and microbial fuel cell, and evaluate the energy storage efficiency and stability;

[0018] S5, Parameter adjustment and optimization: adjust the temperature, PH value and wastewater load operation conditions of microbial fuel cell to optimize the performance of the cell, and adjust the vanadium ion concentration, circulation rate and circulation mode of vanadium-based energy storage medium to improve the energy storage efficiency and stability;

[0019] S6, data analysis and result evaluation: analyze the experimental data of the microbial fuel cell and the vanadium-based energy storage medium, including the variation trend and correlation of the current, voltage, vanadium ion concentration parameters, and evaluate the energy storage performance, electrochemical stability of the VEMS-MFC system, and the advantages and limitations compared with traditional microbial fuel cells.

[0020] Preferably, the material of the cathode in step S1.2 is a copper-based or tin-based nanomaterial.

[0021] Preferably, the anode and cathode materials in step S2.1 are carbon paper or carbon cloth.

[0022] Preferably, the electron transfer medium coated on the anode in step S2.1 is carbon felt.

[0023] Preferably, the microbial suspension in step S2.2 is collected from anaerobic sludge or soil samples.

[0024] The present application has the following advantages:

[0025] 1. The structure design of the vanadium-based energy storage medium-microbial cell coupling system can realize the functions of wastewater purification and CO2 reduction. The soluble organic matter in wastewater is oxidized to CO2 by the microbial electrode of the primary cell, and the generated CO2 can be collected and reduced at the cathode of the electrolytic cell, while the anode of the electrolytic cell undergoes a vanadium-based energy storage material oxidation reaction.

[0026] 2. Due to the intrinsic safety and long service life of the vanadium-based energy storage medium, it can store unstable and inefficient chemical energy, solving the problems of low efficiency and instability of microbial fuel cells. The vanadium-based energy storage medium is first used as the cathode of the electrolytic cell, and then as the anode of the primary cell for direct recycling after the electrochemical reaction is completed, saving the electrode input cost.

[0027] 3. The coupling system uses vanadium-based energy storage medium (redox couple / SSE electrode) to replace the oxygen evolution (OER) reaction, greatly improving the energy efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0028] Fig. 1 The schematic diagram of the vanadium-based energy storage medium part of the present application.

[0029] Fig. 2 The schematic diagram of the microbial fuel cell (MFC) part of the present application.

[0030] Fig. 3 The schematic diagram of the link between the vanadium-based energy storage medium part and the microbial fuel cell (MFC) part of the present application. DETAILED DESCRIPTION

[0031] The specific embodiments of the present application will be further described in detail below with reference to the drawings, and the description of the embodiments will help the skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solutions of the present application.

[0032] As shown in Figs. 1-3 , the present application provides a wastewater treatment method based on a vanadium-based energy storage medium-microbial fuel cell coupled energy storage system, comprising the following steps:

[0033] S1, corresponding preparation work is carried out on the vanadium-based energy storage medium part;

[0034] S1.1, prepare vanadium ion solution: prepare an appropriate amount of vanadium ion solution containing different oxidation states of V 2+ and V 3+ ;

[0035] S1.2, prepare anode and cathode: use materials with good electrical conductivity to prepare anode and cathode, wherein the material of the cathode is copper-based or tin-based nanomaterial, and they are respectively immersed in anode and cathode electrolyte, the cathode and the anode are separated by an ion exchange membrane, the cathode is loaded with efficient carbon dioxide reduction catalyst, and the anode is a vanadium-based reversible redox electron pair, which undergoes oxidation reaction of vanadium energy storage medium;

[0036] S1.3, connect the circuit: connect the anode and the cathode through an external circuit to form a closed circuit;

[0037] S2, corresponding preparation work is carried out on the microbial fuel cell part;

[0038] S2.1, prepare anode and cathode: use materials with good electrical conductivity to prepare anode and cathode, wherein the anode and cathode materials are carbon paper or carbon cloth, and the anode surface is coated with an electron transfer medium, which is carbon felt, and the cathode is a vanadium-based reversible redox electron pair;

[0039] S2.2, prepare microbial suspension: collect microbial suspension from appropriate environment, wherein the microbial suspension is collected from anaerobic sludge or soil sample;

[0040] S2.3, assemble microbial fuel cell: install the anode and the cathode in a sealed electrolytic cell, separate the cathode and the anode by an ion exchange membrane, and connect an external circuit, the organic pollutants in the anode wastewater undergo oxidation reaction to generate CO2, the cathode undergoes reduction reaction of vanadium energy storage medium, V 3+ is reduced to V 2+ , and V 2+ is transmitted to the vanadium-based energy storage medium part to be oxidized to V 3+ , and V 3+Transmission to the microbial fuel cell part;

[0041] S3, assembly of the coupling system: placing the vanadium-based energy storage medium and the microbial fuel cell in the same system, enabling them to share the same electrolytic tank, ensuring proper linking between the two systems, ensuring that the vanadium-based reversible redox electron pair can be switched between the microbial fuel cell and the vanadium-based energy storage medium, so that electrons and ions can be transmitted between them;

[0042] S4, experimental operation: by charge calculation, injecting organic wastewater into the microbial fuel cell for the microorganisms to carry out metabolic reactions and convert chemical energy into electrical energy, while circulating the vanadium ion solution in the vanadium-based energy storage medium to store electrical energy between the anode and the cathode, monitoring the electrochemical indicators of the energy storage medium system and the microbial fuel cell, such as current, voltage, ion concentration changes, and evaluating the energy storage efficiency and stability;

[0043] S5, parameter adjustment and optimization: adjusting the temperature, pH value and wastewater load operating conditions of the microbial fuel cell to optimize the performance of the battery, and adjusting the vanadium ion concentration, circulation rate and circulation mode of the vanadium-based energy storage medium to improve the energy storage efficiency and stability;

[0044] S6, data analysis and result evaluation: analyzing the experimental data of the microbial fuel cell and the vanadium-based energy storage medium, including the trends and correlations of current, voltage, vanadium ion concentration parameters, evaluating the energy storage performance, electrochemical stability of the VEMS (Vanadium-based Energy Storage Medium)-MFC system, and the advantages and limitations compared with traditional microbial fuel cells. It should be noted that the specific experimental operation steps and conditions may vary depending on the experimental equipment and research purposes, therefore, before conducting the experiment, it is recommended to refer to relevant scientific literature and experimental methods to obtain more detailed and accurate operation guidelines.

[0045] The above describes the present application in conjunction with the drawings, and it is obvious that the specific implementation of the present application is not limited to the above manner, as long as various non-essential improvements are made using the concept and technical solution of the present application, or the present application and technical solution are directly applied to other occasions without improvement, all within the scope of protection of the present application.

Claims

1. A wastewater treatment method based on a vanadium-based energy storage medium-microbial fuel cell coupled energy storage system, characterized in that: The method comprises the following steps: S1, corresponding preparation work is carried out on the vanadium-based energy storage medium part; S1.1, Preparation of vanadium ion solution: Prepare a proper amount of vanadium ion solution containing different oxidation states of V 2+ and V 3+ ; S1.2, the anode and the cathode are prepared: the anode and the cathode are prepared by using materials with good electrical conductivity, and they are respectively immersed in the anode and cathode electrolyte, the cathode and the anode are separated by an ion exchange membrane, the cathode is a high-efficiency carbon dioxide reduction catalyst, the carbon dioxide reduction reaction occurs to generate formic acid, and the anode is a vanadium-based reversible redox electron pair, and the oxidation reaction of the vanadium energy storage medium occurs; S1.3, the circuit is connected: the anode and the cathode are connected through an external circuit to form a closed circuit; S2, corresponding preparation work is carried out on the microbial fuel cell part; S2.1, the anode and the cathode are prepared: the anode and the cathode are prepared by using materials with good electrical conductivity, and the surface of the anode is coated with an electron transfer medium, and the cathode is a vanadium-based reversible redox electron pair; S2.2, the microbial suspension is prepared: the microbial suspension is collected from a suitable environment; S2.3, the microbial fuel cell is assembled: the anode and the cathode are installed in a sealed electrolytic cell, the cathode and the anode are separated by an ion exchange membrane, and an external circuit is connected, the organic pollutants in the anode wastewater undergo oxidation reaction to generate CO2, and the cathode undergoes reduction reaction of vanadium energy storage medium; S3, assembly of the coupling system: the vanadium-based energy storage medium and the microbial fuel cell are placed in the same system, so that they can share the same electrolytic cell, and ensure that the vanadium-based reversible redox electron pair can be switched between the microbial fuel cell and the vanadium-based energy storage medium, so that electrons and ions can be transmitted between them; S4, experimental operation: through charge calculation, organic wastewater is injected into the microbial fuel cell for metabolic reaction of microorganisms, and chemical energy is converted into electrical energy, at the same time, vanadium ion solution in the vanadium-based energy storage medium is circulated to store electrical energy between the anode and the cathode, the electrochemical indexes of the energy storage medium system and the microbial fuel cell are monitored, and the energy storage efficiency and stability are evaluated; S5, parameter adjustment and optimization: the temperature, pH value and wastewater load operating conditions of the microbial fuel cell are adjusted to optimize the battery performance, and the vanadium ion concentration, circulation rate and circulation mode of the vanadium-based energy storage medium are adjusted to improve the energy storage efficiency and stability; S6, data analysis and result evaluation: the experimental data of the microbial fuel cell and the vanadium-based energy storage medium are analyzed, including the change trend and correlation of current, voltage, vanadium ion concentration parameters, the energy storage performance, electrochemical stability of the VEMS-MFC system are evaluated, and the advantages and limitations compared with traditional microbial fuel cell are evaluated.

2. The method according to claim 1, wherein the vanadium-based energy storage medium-microbial fuel cell coupled energy storage system is characterized in that: The material of the cathode in step S1.2 is copper-based or tin-based nanomaterial.

3. The method of wastewater treatment based on a vanadium-based energy storage medium-microbial fuel cell coupled energy storage system according to claim 1, characterized in that: The anode and cathode materials in step S2.1 are carbon paper or carbon cloth.

4. The method of claim 1, wherein the vanadium-based energy storage medium-microbial fuel cell coupled energy storage system is characterized by: The electron transfer medium coated on the anode in step S2.1 is carbon felt.

5. The method of wastewater treatment based on a vanadium-based energy storage medium-microbial fuel cell coupled energy storage system according to claim 1, characterized in that: The microbial suspension in step S2.2 is collected from anaerobic sludge or soil samples.

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