技术标准视角下我国污水处理厂尾水人工湿地设计分析

Design analysis of constructed wetlands for treatment of terminal effluent of wastewater treatment plants from technical standard perspective

人工湿地已逐渐应用于我国污水处理厂提标改造和尾水资源化利用工程实践中,并成为一项备受关注的技术。为指导和规范国内各地区污水处理厂尾水人工湿地工程的设计和建设,国家和地方相关职能部门及专业协会发布实施了多部尾水人工湿地技术标准。在全面梳理国内外尾水人工湿地工程应用现状和当前指导尾水人工湿地设计、建设的相关技术标准实施情况的基础上,对不同层面尾水人工湿地技术标准从工艺选型、设计参数等方面进行对比分析。依据尾水人工湿地碳水平调控策略的可行性、经济性并结合实际工程应用可达性的综合分析,确定湿地结构优化、工艺改进、耦合工艺是优化尾水人工湿地工程设计和强化其脱氮效能的较好策略和途径。为保障人工湿地工程安全和正常运营,建议人工湿地工程设计时应依据当地的水文条件,进行湿地的总水量平衡计算。未来应构建基于基质和水生植物选择、工程运营监测等方面的基础数据库,加强技术标准在尾水人工湿地全生命周期中的指导作用。

The constructed wetlands(CWs)technology has been gradually applied to the upgrading and reconstruction of wastewater treatment plants(WWTPs)and the utilization of terminal effluent of WWTPs in China,and has become an important technical research field.Some national and local responsible departments and professional associations have promulgated and implemented several technical standards,which are used to guide and standardize the design and construction of CWs for treatment of terminal effluent of WWTPs.The application status of CWs projects for treatment of terminal effluent of WWTPs at home and abroad and the implementation of relevant technical standards guiding the design and construction of CWs were summarized,and the process selection and structure design parameters in the technical standards of CWs at different levels were compared and analyzed.By comparing the feasibility and economy of the carbon level control strategies of CWs and the accessibility of the actual project applications,it was found that the wetland structure optimization,process improvement and coupling process were the better strategies and pathways to optimize the design of CWs projects and enhance their nitrogen removal efficiency.Meanwhile,in order to ensure the safety and normal operation of CWs projects,it was suggested that the total water balance of wetlands should be calculated under the local hydrological conditions during the design of CWs projects.It was necessary to build a basic database based on substrates and aquatic plant selection,engineering operation monitoring and other aspects to strengthen the guiding role of technical standards in the whole life cycle of CWs.