单室微生物燃料电池产电与脱氮除磷的研究

Electricity generation and recovery of nitrogen and phosphorus in the single-chambermicrobial fuel cell

实验针对空气阴极型单室微生物燃料电池(Microbial Fuel Cell,MFC),研究其产电性能及对实验室模拟废水中有机物、氮和磷元素的去除效果.结果表明,在外电阻为1000Ω的情况下,该电池最大输出电压可达371 m V,最大输出功率密度可达301.6 m W·m^(-2),最大电流密度可达2.4 A·m^(-2),内阻为200Ω.当入水氨氮浓度为4 mmol·L^(-1)时,该电池的产电效果最好,对污染物的去除效果也较好.研究还发现,电池最佳运行周期为72 h,阳极室出水最佳曝气时间为6 h,阳极室出水COD、TN和TP的降解率分别为93.3%、19.7%和44.8%.将阳极液曝气处理后,相对于阳极室入水其TN和TP的总去除率分别可达79.6%和95.2%.另外,通过扫描电镜观察到MFC的阳极液中大多为球形菌,阴极电极表面有针状的结晶形成,经能谱测试为鸟粪石结晶.

An air-cathode single-chamber microbial fuel cell（ MFC） was investigated to study its power generation and the removal of organic matters,nitrogen and phosphorus in the simulated wastewater. With an external resistor of 1000 Ω,the maximum voltage of the MFC reached 371 m V. Besides,its maximum power density and maximum current density were 301.6 m W·m^-2and 2.4 A·m^-2. The internal resistance of the MFC was about 200 Ω from the test. The MFC generated electricity well when the concentration of the NH4 Cl was 4 mmol·L^-1. Also,the degradation rate of pollutants was much better. It was concluded that the optimistic operation time of the MFC was 72 h and the best aeration time of the anolyte was 6 h. The degradation efficiency of chemical oxygen demand,total nitrogen and total phosphorus of the anode chamber effluent are 93.3%,19.7% and 44.8%. After the anolyte was aerated,the removal efficiency of the total phosphorus and total nitrogen increased to 79. 6% and 95. 2% compared with the anode chamber influent. Moreover,through scanning electron microscope capable of energy dispersive spectroscopy（ SEM-EDS）,it was observed that the spherical bacteria accounted for the main part of the bacteria in the anode chamber. And the needle crystals of struvite on the cathode electrode surface of the MFC were also observed.