Abstract: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. Key words:toilet wastewater/ single-chamber membrane-free microbial electrolysis cell/ applied voltage/ denitrification.
图1单室微生物电解池结构示意图 Figure1.Schematic diagram of the structure of single-chamber MEC
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1.School of Environment and Safety Engineering, Changzhou University, Changzhou 213164, China 2.Yixing Eco-Sanitary Manufacture Co.Ltd., Yixing 214205, China Received Date: 2019-06-25 Accepted Date: 2019-10-08 Available Online: 2020-05-06 Keywords:toilet wastewater/ single-chamber membrane-free microbial electrolysis cell/ applied voltage/ denitrification Abstract: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.
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