Preliminary Study Of Microbial Fuel Cell And Photocatalytic Technology Applied To Wastewater Treatment

Nowadays energy and environmental issues were two biggest problems in the world. Microbial fuel cell(MFC) is a technology that could change chemical energy into electrical energy, which is able to meet these two requirements.In this study, we started the MFC system by inoculating the bacterial suspension of staphylococcus NJUST-1. Voltage was first detected at5days later, and was stable in10to15days. The CV analysis showed that the anode performance was increased by the bacterial load. We did a study of resuming start at the end of a cycle. The result showed that under the condition of incompletely replacing the anolyte, The presence of oxygen became the limiting factor, when oxygen was consumed, the system re-entered resuming start. Supplementing carbon source had little effect of voltage recovery and the loss of the bacterial in the solution affecting it but not serious. Transplantating the anode electrode could quickly start a new cell and the voltage of the original one revoved rapidly because it retained a large number of bacteria.Then we used glucose, actual sewage or actual industrial waste water to run the MFC system. We found that improving glucose concentration could stimulate Voltage rise,however,the accumulation of the metabolites would inhibit the production when the concentration reached a high level.The degradation and the electricity production of the actual sewage were also very well.Voltage reached500mV in3×5days.5days average degradation rate of COD was88%,ammonia nitrogen was84%. MFC had a weak performance of industrial wastewater, which could only produce less than50mV peak voltage,but it had a well performance of COD degradation,which showed that there was a lot of non-electricity production reaction in the degradation process.Photocatalyst degradation as an advanced oxidation method is increasingly being used in the field of water treatment.We prepared photocatalyst by coating ZnO on BC. The SEM results showed that the nanoparticles had uniform aspect ratio, which length was about2-4μm, diameter was about0.2-0.3μm, and there was no agglomeration. XRD results showed that the load is high. Photocatalytic degradation results showed that the removal efficiency of DDNP was98%, TNT was75%. Liquid Chromatography results showed that photocatalytic had a better degradation rate than MFC. We used the photocatalytic degradation as the pretreatment methods which could improve the electricity production performance of MFC.