在微生物燃料电池生物阴极实现硝化过程的试验研究

Experimental study on the nitrification process in the bio-cathode of microbial fuel cells

微生物燃料电池(MFCs)去除废水中有机物已经进行了大量研究,然而MFCs去除营养盐的能力较弱是将来产业化的障碍之一。研究了以铁锰氧化细菌为催化剂的生物阴极稳定产电的同时实现生物硝化反应的可行性以及其影响因素,并对生物阴极中的铁锰氧化细菌以及硝化细菌进行了计数。以铁锰氧化细菌为催化剂的生物阴极MFCs的启动时间为150～200h,运行稳定时,最高电压达600 mV。研究表明,该生物阴极在稳定产电的同时实现了生物硝化反应,其NO3--N的生成速率为0.792mg/(L.h),NO2--N最高质量浓度为1.56mg/L;阴极进水中NH4+-N以及DO浓度均是重要影响因素;对生物阴极中的铁锰氧化细菌以及硝化细菌计数结果表明,铁锰氧化细菌为7.5×106 MPN/mL,硝化细菌为9.3×105 MPN/mL。

Oxidation of organic substrate in microbial fuel cells （MFCs） was verified in last years. However,the poor capacity of MFCs in nitrification limits its future industrialization. In this thesis,the bio-cathode MFCs with fer- ro/manganese-oxidizing bacteria as catalyst was established to investigate the feasibility of achieving the nitrification as well as power generation. In addition, the amount of ferro/manganese-oxidizing bacteria and nitrifying bacteria in the bio-cathodes were counted. Results showed that 150-200 hours was needed to start the bio-cathode MFCs. The maximum voltage was 600 mV when the bio-cathode MFCs was operated stably. The nitrification rate was 0. 792 mg/（L ~ h）, while the highest concentration of NO^--N was 1.56 mg/L. The influent N H＋ -N, dissolved oxygen （DO） concentrations played an important role in the operation of the bio-cathode. The amount of ferro/manganese-oxidizing bacteria and nitrifying bacteria in the biocathode were 7.5 ×10^6 and 9.3 ×10^5 MPN/mL respectively.