Zhou Ming, Cao Jiashun, Qiu Yuanyuan, Lu Yanhong, Guo Jinyan, Li Chao, Wang Yantang, Hao Liangshan, Ren Hongqiang
Key Laboratory of Integrated Regulation and Resource Development On Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, China.
College of Environment, Hohai University, Nanjing, 210098, China.
Environ Sci Pollut Res Int. 2023 Apr;30(17):51245-51260. doi: 10.1007/s11356-023-25860-6. Epub 2023 Feb 21.
Three anodic biofilm electrode coupled CWs (BECWs) with graphite (E-C), aluminum (E-Al), and iron (E-Fe), respectively, and a control system (CK) were constructed to evaluate the removal performance of N and P in the secondary effluent of wastewater treatment plants (WWTPs) under different hydraulic retention time (HRT), electrified time (ET), and current density (CD). Microbial communities, and different P speciation, were analyzed to reveal the potential removal pathways and mechanism of N and P in BECWs. Results showed that the optimal average TN and TP removal rates of CK (34.10% and 55.66%), E-C (66.77% and 71.33%), E-Al (63.46% and 84.93%), and E-Fe (74.93% and 91.22%) were obtained under the optimum conditions (HRT 10 h, ET 4 h, CD 0.13 mA/cm), which demonstrated that the biofilm electrode could significantly improve N and P removal. Microbial community analysis showed that E-Fe owned the highest abundance of chemotrophic Fe(II) (Dechloromonas) and hydrogen autotrophic denitrifying bacteria (Hydrogenophaga). N was mainly removed by hydrogen and iron autotrophic denitrification in E-Fe. Moreover, the highest TP removal rate of E-Fe was attributed to the iron ion formed on the anode, causing co-precipitation of Fe(II) or Fe(III) with PO-P. The Fe released from the anode acted as carriers for electron transport and accelerated the efficiency of biological and chemical reactions to enhance the simultaneous removal of N and P. Thus, BECWs provide a new perspective for the treatment of the secondary effluent from WWTPs.
构建了分别与石墨（E-C）、铝（E-Al）和铁（E-Fe）耦合的三个阳极生物膜电极连续流湿地（BECWs）以及一个对照系统（CK），以评估不同水力停留时间（HRT）、通电时间（ET）和电流密度（CD）条件下污水处理厂（WWTPs）二级出水对氮和磷的去除性能。分析了微生物群落和不同的磷形态，以揭示BECWs中氮和磷的潜在去除途径及机制。结果表明，在最佳条件（HRT 10小时、ET 4小时、CD 0.13 mA/cm²）下，CK（总氮和总磷去除率分别为34.10%和55.66%）、E-C（66.77%和71.33%）、E-Al（63.46%和84.93%）和E-Fe（74.93%和91.22%）获得了最佳平均总氮和总磷去除率，这表明生物膜电极可显著提高氮和磷的去除效果。微生物群落分析表明，E-Fe拥有最高丰度的化学营养型亚铁（脱氯单胞菌属）和氢自养反硝化细菌（嗜氢菌属）。在E-Fe中，氮主要通过氢和铁自养反硝化作用去除。此外，E-Fe的最高总磷去除率归因于阳极形成的铁离子，导致亚铁或铁离子与磷酸根发生共沉淀。阳极释放的铁作为电子传输载体，加速了生物和化学反应效率，以增强氮和磷的同步去除。因此，BECWs为处理WWTPs的二级出水提供了新的视角。
