滤渠-塘组合系统对城市旅游区降雨径流污染的离线截控作用

提出了一种控制城市旅游区降雨径流污染的滤渠-塘离线组合处理系统,并研究了该系统对降雨径流污染的离线截控作用.结果表明:无论从单次降雨事件还是从年度上分析,该系统通过有效地分流初期污染降雨径流,均可降低降雨径流中污染物的浓度和体积平均粒径,并对降雨径流中污染物的负荷具有较高的持留效率,是一种高效的处理系统,比较适用于土地利用相对紧张的城镇区域.2005年该系统对降雨径流中总悬浮物(TSS)、化学需氧量(COD)、总氮(TN)和总磷(TP)负荷的年持留率分别达到86.4%、85.5%、83.9%和82.9%.以2005年6月26日的次降雨事件为例,该系统对降雨径流水量的削减率为67.9%,对污染物中各种形态氮的去除效率高于磷,对TSS、COD、TN和TP负荷的持留率分别为97.0%、89.2%、94.9%和96.2%.该系统还可以有效地拦截降雨径流中的大部分颗粒物.

Off-line control of runoff pollution by filtering ditch-pond system in urban tourist areas

An off-line filtering ditch-pond system for controlling storm runoff pollution in urban tourist areas was developed,which could retain the first flush effectively,resulting in the decrease of pollutant concentration and suspended solid average grain size,and the improvement of pollutant retention in runoff.This system could be an effective treatment system for storm runoff pollution,particularly for the scarcity of available land use in urban areas.In 2005,the yearly retention rates of TSS,COD,TN and TP were 86.4%,85.5%,83.9% and 82.9%,and during a storm event on June 26,the retention rates of runoff volume,TSS,COD,TN and TP were 67.9%,97.0%,89.2%,94.9% and 96.2%,respectively.This system could also retain most of the suspended solids in runoff.