The results of the 16th "WPG Cup" Excellent Paper Awards by Water & Wastewater Engineering journal were officially announced recently. The paper "Anaerobic-Oxic-Anoxic (AOA) Process in Wastewater Treatment: Principles, Developments, and Application" was awarded the only Special Prize of the past three editions of the competition. The corresponding author is Academician Yongzhen Peng, who is the leader of the National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology. The first author is postdoctoral researcher Xinjie Gao. The "WPG Cup" Excellent Paper Awards by Water & Wastewater Engineering journal were established in 2011, and held annually, which are recognized as one of the highest honors for scientific papers in China's water treatment industry.

The award-winning paper, "Anaerobic-Oxic-Anoxic (AOA) Process in Wastewater Treatment: Principles, Developments, and Application" provides a systematic review of the background, research process, and the full-cycle application of the AOA process. The study pointed out that the AOA process achieved advanced nitrogen and phosphorus removal without external carbon sources through three key features: (1) cancelling recirculation of nitrified liquor from the oxic zone to the anoxic zone, (2) a significantly shorter hydraulic retention time in the oxic zone compared to the anoxic zone, (3) full utilization of raw water carbon sources for nitrogen and phosphorus removal. In addition, the process boasts notable advantages, including low sludge production, reduced aeration energy consumption, and a simple process flow.

The paper also summarizes the nationwide applications of the AOA process. Since the completion of the first AOA municipal wastewater treatment plant in 2021, with a designed capacity of 30,000 m³/d, a total of 12 newly built or upgraded wastewater treatment plants across China have adopted the AOA process. These projects are located in Shenzhen and Zhongshan in Guangdong Province, Guiyang in Guizhou Province, and Yixing in Jiangsu Province.