2种生态植草沟对路面径流净化效果的对比

将铝污泥生物填料与台阶型植草沟相结合,构建台阶型生态植草沟系统,现场比较台阶型生态植草沟和常规生态植草沟对路面径流的净化效果。结果表明:在2次降雨(大雨、中雨)事件中,台阶型生态植草沟径流量削减效果优于常规植草沟,径流总量削减率分别为63.04%和55.21%,峰值流量显著降低,峰值时间至少延迟24~30 min;台阶型生态植草沟具有较好的水质控制及污染负荷削减效果,对径流中SS、COD_Cr、NH₃-N、TN和TP浓度削减率分别可达79.54%、67.08%、34.75%、63.61%和78.36%,对总量削减率分别可达92.44%、87.83%、74.29%、84.45%和90.31%,出流水质均优于GB 3838—2002《地表水环境质量标准》Ⅳ类水质标准。台阶型生态植草沟对路面径流可取得较好的水质控制及污染负荷削减效果,具有较好的推广应用价值。

Comparison of the effect of two kinds of ecological grass swales on road runoff purification

The biological packing of aluminum sludge was combined with the stepped ecological grass swale to construct stepped ecological grass swale system, and the effects of stepped ecological grass swale and conventional grass swale on the road runoff purification were compared. The results showed that effect of stepped ecological grass swale on the runoff volume reduction was better than that of conventional grass swale in the two rainfall events, and the reduction rate of runoff volume was 63.04% and 55.21%, respectively. The peak flow was significantly decreased, and the peak time was delayed at least 24-30 min. The stepped ecological grass swale had good water quality control and pollution load reduction effect. The concentration reduction rates of SS, CODCr, NH3-N, TN and TP in the runoff could reach 79.54%, 67.08%, 34.75%, 63.61% and 78.36%, respectively, and the reduction rates of the runoff volume could reach 92.44%, 87.83%, 74.29%, 84.45% and 90.31%, respectively. The effluent water quality was better than that of Class Ⅳ requirement of Environmental Quality Standards for Surface Water (GB 3838-2002). The stepped ecological grass swale could achieve better water quality control and pollution load reduction effect on road runoff, and thus had a good popularization and application value.