北京市城镇污水再生利用现状与潜力分析

北京市水资源严重匮乏，污水再生利用是支撑城市可持续发展和生态文明建设的重要途径和必然选择。近年来，北京市总用水量逐年递增，其中生态用水量增幅最大，截至2018年已达到13.4亿m3，占全市用水总量的34.1%。同年，北京市城镇污水处理能力达到19.1亿m3，污水处理率达到93.4%，污水处理量达到16.7亿m3，90%以上处理出水的COD、氨氮、总磷指标均已达到GB/T 18921—2019《城市污水再生利用景观环境用水水质》（湖、库）。目前，北京市的污水再生利用率约为56.3%。如将以色列82%的污水再生利用率作为发展目标，未来仍然有4.9亿m3的增长空间（以2018年北京市污水处理量为计算依据），相当于2018年南水北调供水量的53%、全市生态用水量的37%。北京市农业、工业、生活和生态用水均存在再生水利用潜力。但污水再生水利用不同于常规水资源利用，目前利用体系仍有需要完善的部分，需要政策、科研、宣传教育等多方面提供支持。污水再生利用是解决北京市水资源短缺问题的重要途径，未来发展潜力巨大。

MUNICIPAL WASTEWATER RECLAMATION IN BEIJING:STATE-OF-THE-ART AND FUTURE POTENTIAL

The water source is in serious shortage in the city of Beijing, and wastewater reclamation is an important and inevitable approach to support the sustainable development and ecological civilization construction of Beijing. In recent years, the total water usage of Beijing increased gradually, especially the ecological water usage. Up to 2018, the ecological water use of Beijing increased to 1.34 billion m3, accounting for 34.1% of the total water usage. In 2018, the municipal wastewater treatment capacity of Beijing was 1.91 billion m3, wastewater treatment rate was 93.4%, and the amount of treated municipal wastewater was 1.67 billion m3. Furthermore, over 90% of the effluent from municipal wastewater treatment plants reached a superior water quality compared with The Reuse of Urban Recycling Water-Water Quality Standard for Scenic Environment Use (GB/T 18921-2019), in the aspects of COD, ammonia and total phosphorus. The current wastewater reclamation rate of Beijing was about 56.3%. Considering the wastewater reclamation rate of Israel (82%) as the development goal, and taking the wastewater treatment amount of Beijing in 2018 as the calculation basis, there was still over 0.49 billion m3 as the growth potential. This potential accounted for 53% of the ecological water use of Beijing, or 37% of the amount of South-to-North Water Transfer Project in 2018. There is potential for agricultural, industrial, municipal and ecological water reuse of Beijing. However, wastewater reclamation is different from conventional water resources utilization. The wastewater reuse system in Beijing still needs improvement, including political, research, publicity and educational supports. Ecological environment supplement with reclaimed water is necessary to solve water shortage of Beijing and has great potential in future development.