Insights into nitrogen removal from domestic wastewater by a novel divided-flow aerobic–anoxic reactor without external carbon source
摘要
This study evaluates the performance of a novel aerobic postanoxic baffled reactor designed for nitrification and denitrification of domestic wastewater without an external carbon source. Instead, the raw wastewater is divided between the aerobic zone at the beginning of the plug flow and the postanoxic zone. The reactor was installed at a wastewater treatment plant to feed on real domestic wastewater from the primary settling tank. The performance of the reactor was evaluated under varying flow distribution ratios, ammonia loadings, and with the inclusion of biological media to assess treatment efficiency in subsequent compartments of the baffled reactor. The key parameters, such as COD, TN, NH₄+, and NO₃−, were monitored along the reactor. Results revealed that dividing the flow and adding biological media significantly improved NH₄+ and NO₃− removal, indicating enhanced nitrification and denitrification. The reactor maintained its performance at different influent ammonia concentrations reaching 400 mg/L when an 80% aerobic to 20% anoxic flow distribution was employed. High-throughput sequencing identified dominant bacterial communities contributing to nitrogen transformations. These findings provide critical insights into optimizing reactor configurations for sustainable wastewater treatment.