Microbial fuel cell and method for treating wastewater by using same

Abstract

The invention relates to a microbial fuel cell and a method for treating wastewater by using the same. The microbial fuel cell comprises a main reaction zone 1, a biological selection and adjustment zone 2, an overflow water outlet trough 3, a perforated water distribution pipe 4, a biological positive electrode 5, an air negative electrode 6, an electrode support 6a, an electrode clamping slot 6b, an positive and negative electrode jack sealing ring 7, a reference electrode 8, PH and DO electrode jacks 9-I and II, an outer resistor 10, a water inlet pipe 11, a monitoring hole 12, evacuation pipes 13 and 14, and a water outlet pipe 15. According to the microbial fuel cell and the method disclosed by the invention, negative electrode aeration of the MFC (microbial fuel cell) is ingeniously avoided by using a capillary action, the energy consumption is reduced and the oxygen mass transfer efficiency of a negative electrode of the MFC is improved; stable and high-efficient denitrification and carbon removal can be realized, the COD (Chemical Oxygen Demand) removal rate can reach 75% to 94.4%, and the TN (total nitrogen) removal rate is 42% to 99.9%.

Description

technical field [0001] The invention belongs to the technical field of sustainable biological treatment of wastewater, in particular to a microbial fuel cell and a method for treating wastewater. technical background [0002] The spread of the energy and environmental crisis is becoming a major bottleneck restricting human development in the 21st century. However, with the rapid development of my country's economy, a large amount of waste water is produced every year, polluting the environment and endangering the health of residents. Pollutants in wastewater are usually discharged after traditional biological anaerobic and aerobic aeration-physical and chemical treatment, but the removal of pollutants in the above process not only consumes a lot of energy, but also produces a large amount of sludge, resulting in high treatment costs and more importantly, pollution A large amount of chemical energy contained in the food is wasted in vain. Therefore, it is urgent to develop ...

AI Technical Summary

Problems solved by technology

[0003] Although MFCs technology has the advantages of both pollutant removal and energy recovery, there are still some problems: 1) The dual-chamber system requires an additional diaphragm, which is likely to cause a pH gradient on both sides of the membrane and weaken the metabolic activity of microorganisms, and it is expensive, increasing the cost ( Proton exchange membrane is about 4000~12000 RMB / m 2 ); 2) In the MFCs system without diaphragm, the cathode needs to use expensive precious metals as catalysts (the price of 5% platinum carbon is 118,980 yuan / kg); 3) Potassium ferricyanide, potassium permanganate or dichromic acid Potassium and other chemical oxidants are used as electron acceptors, which have pollution and regeneration problems, which are not conducive to practical application; oxygen, as an electron acceptor, has the advantages of wide source, cheap and easy to obtain, and the product is water-free pollution, etc., but the solubility of oxygen in water is limited. Dissolved oxygen utilization efficiency is low, resulting in a large amount of aeration energy consumption

Patent No. 201020139304.3 discloses an anammox microbial fuel cell, inoculated with anammox bacteria to start the denitrification of the microbial fuel cell, although aeration is not required, but the nitrification product nitrite needs to be added as an electron acceptor, and it is anaerobic Ammonium oxidizing bacteria have the disadvantages of slow growth, being easily affected by temperature, and demanding water requirements.

Patent No. 201010166534.3 discloses a rotating biological cathode microbial fuel cell and its sewage treatment method, but the rotating biological cathode not only needs kinetic energy to drive, but also the rotation of the electrode easily entrains oxygen and transfers to the bottom anode, thereby reducing its power generation performance

Patent No. 201310745120.X discloses a preparation method of air cathode sheets of microbial fuel cells, but the preparation procedures of the diffusion layer and the catalytic layer are relatively cumbersome, which limits its practical application

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