蓄水绿化屋面对雨水径流中污染物的去除效果

Removal Efficiency of Pollutants in Rainwater Runoff by Green Water-storing Roof

屋面作为城区不透水区域的主要组成部分，是造成城市面源污染的重要因素之一。为此，根据屋面雨水径流的特点设计了蓄水绿化屋面系统，并通过比较屋面雨水和城市蓄水绿化屋面处理后出水的水质情况，分析了其对污染物的去除效果。结果显示，城市蓄水绿化屋面对屋面雨水径流中的SS、COD、TN、TP有明显的去除效果，去除率分别可达（80％～90％）、（50％-70％）、（50％-70％）、（40％～70％）。雨水径流经过城市蓄水绿化屋面处理后，其水质可达到《城市污水再生利用城市杂用水水质》（GB／T18920-2002）的要求。该研究为城市屋面雨水资源化利用工程的实施提供了一定的理论依据。

As one of the main components of urban impervious area, roof is one of the factors leading to the urban non-point source pollution. A green water-storing roof system was designed according to the characteristics of roof rainwater runoff. The removal efficiency of pollutants was analyzed by comparing the quality of raw rainwater and treated effluent. The results show that the urban green water-storing roof has a high removal efficiency of SS, COD, TN and TP in roof rainwater runoff. The removal rates of SS, COD, TN and TP are 80% to 90%, 50% to 70%, 50% to 70% and 40% to 70% respectively. After treated by the green water-storing roof, the roof rainwater can meet the requirement of Reuse of Urban Recycling Water-Water Quality Standard for Urban Miscellaneous Water Consumption （GB/T 18920 -2002）. The study provides some theoretical basis for the urban roof rainwater resource utilization.