Abstract：
Achieving economic and efficient removal of nutrients in mainstream wastewater treatment plants (WWTPs) continues to be a challenging research topic. In this study, a continuous-flow anaerobic/aerobic/anoxic system with sludge double recirculation (AOA-SDR), which integrated partial nitrification (PN), endogenous denitrification (ED) and nitrite-type denitrifying phosphorus removal (nDNPR), was constructed to treat real carbon-limited municipal wastewater. The average effluent concentrations of total inorganic nitrogen (TIN) and PO43--P during the stable operation period were 1.8 and 0.3 mg/L, respectively. PN was achieved with an average nitrite accumulation ratio of 90.4 % by combined strategies. Adequate storage of polyhydroxyalkanoates and glycogen in the anaerobic zone promoted the subsequent nitrogen removal capacity. In the anoxic zone, nitrite served as the main electron acceptor for the denitrifying phosphorus removal process. Mass balance analysis revealed that nDNPR contributed to 23.6 % of TIN removal and 44.7 % of PO43--P removal. The enrichment of Nitrosomonas (0.45 %) and Ellin 6067 (1.31 %), along with the washout of Nitrospira (0.15 %) provided the bacterial basis for the successful implementation of PN. Other dominant endogenous heterotrophic bacteria, such as Dechlormonas (10.81 %) and Candidatus Accumulibacter (2.96 %), ensured simultaneous nitrogen and phosphorus removal performance. The successful validation of integrating PN, ED and nDNPR for advanced nutrient removal in the AOA-SDR process provides a transformative technology for WWTPs.
摘要：
在主流污水处理厂（WWTP）中实现经济有效的养分去除仍然是一个具有挑战性的研究课题。在这项研究中,具有污泥双重再循环的连续流厌氧/好氧/缺氧系统（AOA-SDR），综合部分硝化(PN)，内源反硝化(ED)和亚硝酸盐型反硝化除磷(nDNPR),是为了处理真正的碳限制城市污水而建造的。稳定运行期间总无机氮(TIN)和PO43--P的平均出水浓度分别为1.8和0.3mg/L,分别。通过组合策略，PN的平均亚硝酸盐积累率为90.4％。多羟基链烷酸酯和糖原在厌氧区的充足储存促进了随后的脱氮能力。在缺氧区，亚硝酸盐是反硝化除磷过程的主要电子受体。质量平衡分析表明，nDNPR对TIN的去除率为23.6％，对PO43--P的去除率为44.7％。Nitrosomonas(0.45%)和Ellin6067(1.31%)的富集,随着Nitrospira的清除（0.15％），为成功实施PN提供了细菌基础。其他优势内源性异养细菌，如Dechlormonas（10.81％）和念珠菌（2.96％），保证了同步脱氮除磷性能。整合PN的成功验证，在AOA-SDR过程中用于高级养分去除的ED和nDNPR为WWTP提供了变革性技术。
