| Microbial fuel cell(MFC)is a new technology that uses bacteria to generate electricity.Electrochemically active bacteria are attached to the anode.The electrons generated by the substrate are transferred to the cathode through an external circuit,and eventually bind to the electron acceptor to form a loop.The bacteria achieve the removal of pollutants by decomposing the matrix when electricity is generated,so this technology has an important impact in alleviating the energy crisis and water environment pollution.During the expansion study in laboratory,the volume of the devices involved ranges from 1L to 100 L,and the power generation is within 0.2-200 W / m3.However,less research has taken into consideration both economic performance and operational performance,and no reliable energy storage equipment has been connected to conduct electrical energy utilization experiments.Therefore,the requirements for practical scale applications have not been met.In this paper,in order to solve such problems,suitable scalable MFC stack configurations were constructed,and the effects of different configurations and connection methods on the performance of the MFC stack were studied in combination with independently designed energy storage circuits,and a reliable MFC stack process plan was formed finally.Two different types of MFC single cells were designed and manufactured,including wide-type MFC and narrow-type MFC.The performance test was performed 60 days after startup,and the maximum power density(Pmax)of the wide-type MFC was found to be 55.12 W / m3,corresponding to an absolute power of about 0.44W;while the maximum power density of the narrow-type MFC was increased by 11.9% compared to the wide-type MFC with a better power generation performance.The narrow MFC had a smaller electrode pitch and a smaller internal resistance,so it exhibited better power generation performance.However,in terms of COD removal capacity,the COD removal rate of wide-type MFC was 94.3%,which was higher than that of narrow-type MFC.Therefore,wide-type MFC can be applied in the field of pollution removal,and narrow-type MFC can be applied in the field of energy recovery.A suitable MFC stack operation process for scale-up was developed,mainly by studying the performance of WMFCs and NMFCs stacks.Starting from the circuit connection method,the number of single battery connections,and the connection materials,the operating performance of the two stacks was tested.It was found that the parallel mode was more suitable for energy recovery of the MFC stack.In addition,in terms of connection materials,the stack performance of copper,brass,tin-plated copper,and tin-plated brass as parallel materials was studied.It was found that when the copper was switched to brass,the Pmax of WMFCs decreased by 5.09%;When the copper was switched to tin-plated copper,the Pmax of WMFCs decreased by 3.06%.In the investigation of the effect of material life on stack performance,it was found that the decrease in Pmax with the increase of the placement time under the condition of copper parallel connection was faster than that of the tin-plated copper parallel condition.Therefore,in combination with power generation performance,material life and economy,tin-plated copper is a suitable parallel material.Two 40 L stacks were constructed,and it was found that WMFCs are superior to NMFCs in terms of COD removal capacity and power generation efficiency,so WMFCs is a suitable stack for scaling up.An energy storage circuit that can recover the energy generated by MFC was designed.The main core components were two chips,TPS61200 and BL4056 B.After connecting to two 40 L stacks,it was found that WMFCs can charge the battery power from 0 to 100% after 2 cycles,and NMFCs can charge from 0 to 83%,so WMFCs have better power generation efficiency.In the economic analysis,it was found that the preferred MFC stack operation process scheme had a cost reduction of 42.25% compared to a typical PS-MFC,which can be reduced to the level of ?40425/ m3. |
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