折流式人工湿地对矿区降雨径流的净化研究

根据陕西省渭南市蒲白矿区降雨径流的水质和水量特征，采用新型折流式人工湿地对人工湿地不同运行阶段模拟降雨径流的净化效果进行了对比，分析了COD_Cr，SS，TN，TP，NH₄⁺-N以及重金属Pb，Zn，Cu在湿地系统中的沿程变化，探讨人工湿地的主要去除机制。结果表明:人工湿地对COD_Cr，TP，TN，NH₄⁺-N，SS的平均去除率分别为82.3%，65.9%，71.2%，73.5%，94.8%，对重金属Pb，Zn，Cu的平均去除率分别为91.3%，94.5%，81.2%，对重金属的去除率基本高于对营养元素的去除率；除了TN外，折流式人工湿地系统出水各污染物均达到《地表水环境质量标准》（GB3838—2002）Ⅲ类质量标准，其中TN达Ⅳ类标准，出水重金属Pb，Zn，Cu均能达地表Ⅲ类水标准。降雨径流各污染物主要在人工湿地的第1格被去除，其中，COD_Cr，TP，SS和Pb均有一半以上的去除率发生在第1格。随着人工湿地沿程进水浓度的增加，其去除率逐渐下降。研究表明，折流式人工湿地系统对矿区降雨径流的净化效果显著，并且该湿地系统具有较强抗冲击负荷能力，可用于城市地面径流污染的控制和雨水利用。

Purification Effects of Baffled Constructed Wetland on Rain Runoff in the Mining Area

According to water characteristics of the rain runoff in a catchment of Pubai mining area,Weinan,an improved baffled constructed wetland (BCW) was used for purification experiment study of simulated and on-the-spot rain runoff.The purification effects of simulated rain runoff were compared in different operated phases of BCW.Meanwhile,the variation of the pollutants (CODCr,SS,TN,TP,NH4+-N,Pb,Zn and Cu) along the BCW and their removal mechanism were analyzed and discussed,respectively.In the purifica tion study of on-the-spot rain runoff,removal rates of CODCr,SS,TN,TP,NH4+-N were 82.3％,65.9％,71.2％,73.5％ and 94.8％,respectively,removal rates of Pb,Zn and Cu were 91.3％,94.5％and 81.2％,respectively,the effluent met the grade [.In the simulated experiment,the effluent water quality of BCW system met the needs of Environmental Quality Standard for Surface Water (GB3838-2002) Ⅲ,TN met V,and most of the pollutants were removed in the front of the BCW,especially CODCr,TP,SS and Pb.The removal rates gradually decreased with the units.In total,there was remarkable treatment performance of the mining rain runoff when BCW system was used.BCW system can also withstand strong shock load.Moreover,and can be applied to control urban surface runoff pollution and use the rainwater.