State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
J Environ Sci (China). 2010;22(1):40-6. doi: 10.1016/s1001-0742(09)60072-3.
The characteristics of urban runoffs and their impact on rainwater utilization and storm pollution control were investigated in three different functional areas of Zhengzhou City, China. The results showed that in the same rain event the pollutant loads (chemical oxygen demand (COD) and total suspended solids (TSS)) in the sampling areas were in the order of industrial area > commercial area > residential area, and within the same area the COD and TSS concentrations of road runoffs were higher than those of roof runoffs. The first flush effects in roof and road runoffs were observed, hence the initial rainwater should be treated separately to reduce rainwater utilization cost and control storm pollution. The initial roof rainfall of 2 mm in residential area, 5 mm in commercial area and 10 mm in industrial area, and the initial road rainfall of 4 mm in residential area and all the road rainfall in commercial and industrial areas should be collected and treated accordingly before direct discharge or utilization. Based on the strong correlation between COD and TSS (R2, 0.87-0.95) and the low biodegradation capacity (biochemical oxygen demand BOD5/COD < 0.3), a sedimentation process and an effective filtration system composed of soil and slag were designed to treat the initial rainwater, which could remove over 90% of the pollutant loads. The above results may help to develop better rainwater utilization and pollution control strategies for cities with water shortages.
本研究调查了中国郑州市三个不同功能区的城市径流特征及其对雨水利用和雨水污染控制的影响。结果表明，在同一降雨事件中，采样区域的污染物负荷（化学需氧量（COD）和总悬浮固体（TSS））顺序为工业区>商业区>居民区，且在同一区域，道路径流的 COD 和 TSS 浓度高于屋顶径流。观察到屋顶和道路径流的初期冲刷效应，因此应单独处理初期雨水，以降低雨水利用成本并控制雨水污染。在居民区应收集和处理初始屋顶降雨 2mm，商业区初始屋顶降雨 5mm，工业区初始屋顶降雨 10mm，且居民区初始道路降雨 4mm 和商业区和工业区的所有道路降雨都应收集和相应处理，然后再直接排放或利用。基于 COD 和 TSS 之间的强相关性（R2，0.87-0.95）和低生物降解能力（BOD5/COD<0.3），设计了沉淀过程和由土壤和炉渣组成的有效过滤系统来处理初期雨水，可去除超过 90%的污染物负荷。以上结果可能有助于为缺水城市制定更好的雨水利用和雨水污染控制策略。
