单室无膜微生物电解池对厕所废水的脱氮处理

微生物电解池(MEC)能有效应用于污水处理。以尿液为主的厕所废水具有C/N低、含氮量高的特点，采用单室无膜MEC以间歇进水方式处理宜兴某景区厕所废水，研究了不同溶解氧、外加电压下的脱氮效果。实验结果表明，在控制较低溶解氧(DO<1 mg·L−1)条件下，外加电压为0.8 V时的脱氮效果最好，氨氮去除率为99.56%，总氮去除率为70.51%，${rm{NO}}_2^ - $-N最大累积量为46.94 mg·L−1，浊度去除率为96.76%。菌群高通量分析结果显示，MEC电解池阳极优势菌群为Thauera、Phycisphaera和Nitrospiral等，其相对丰度分别为28.7%、20.8%、16.2%，其中Thauera是一种电活性菌群具有较高电化学活性的微生物；阴极优势菌群为Nitrosomonas和Thermomonas等，其相对丰度分别为18.6%和28.4%。单室无膜MEC脱氮工艺研究可为厕所废水处理提供技术参考。

Denitrification treatment of single-chamber membrane-free microbial electrolysis cell for toilet wastewater

Microbial electrolysis cell (MEC) can be effectively used in sewage treatment. Toilet wastewater dominated by urine has the characteristics of low C/N and high nitrogen content. A single chamber membrane-free MEC was used to treat toilet wastewater in Yixing scenic spot by intermittent feeding protocol. The denitrification effect under different dissolved oxygen and applied voltage was studied. The experimental results showed that under the condition of low dissolved oxygen (DO<1 mg·L−1) and applied voltage of 0.8 V, MEC achieved the best denitrification effect, the ammonia nitrogen removal rate was 99.56%, the total nitrogen removal rate was 70.51%, the maximum accumulation of ${rm{NO}}_2^ - $-N was 46.94 mg·L−1, and the turbidity removal rate was 96.76%. The results of high throughput microflora analysis showed that the dominant bacterial at anode of MEC were Thauera, Phycisphaera and Nitrospiral, and their relative abundance ratios were 28.7%, 20.8% and 16.2%, respectively. Of which Thauera was a kind of microorganism with high electrochemical activity. Nitrosomonas and Thermomonas were the dominant bacterialat cathode of MEC, their relative abundance ratios were 18.6% and 28.4%, respectively. Therefore, single-chamber membrane-free MEC denitrification process can be considered as a technical reference for toilet wastewater treatment.