基于Monte Carlo法的城市雨水径流污染负荷模拟

为了评价流域雨水径流对受纳水体的污染程度和为城市雨水管理、受纳水体水质控制及规划提供依据,把以物理过程为基础的模拟特征融入到概率模型中,建立了城市雨水径流污染负荷的概率模型,并用Monte Carlo随机抽样法,对长期的径流污染负荷进行了模拟试验,得出流域径流污染负荷的分布特性及其特征值。以某市一小区的TP负荷为例进行了验证,模拟结果与实测结果较为一致。

基于BP神经网络的雨水径流污染负荷评估模型

针对当前非点源污染中雨水径流水质监测数据匮乏而难以评估其污染负荷的弊端,将BP神经网络模型引入评估雨水径流污染负荷问题。使用监测区域2014-2015年20场次降雨作为样本数据,以主成分影响因子作为输入量,污染物EMC(以SS计)作为输出量,构建三层BP神经网络模型,通过SPSS和MATLAB工具计算相应年份的雨水径流污染负荷,结合Schueler法构建年污染负荷模型并对计算结果进行应用验证。结果表明,其相对误差为2.7%,精度高,适应能力强,基于BP神经网络构建模型是评估雨水径流污染负荷的一种有效方法。

Pollution control of outfall of rainwater-sewage confluence in old town

In order to improve water quality of middle ancient canal in Zhenjiang city a pollution control project was carried out.The research area is the middle catchment area of the ancient canal river system in the old town of Zhenjiang. The specific research object is the runoff of the outfall of rainwater-sewage confluence in the area. On the basis of detecting and analyzing the water yield and water quality of the runoff of rainwater-sewage confluence a combined technology which contains four independent continuous processes for lowering pollution load was developed and system equipment was established and put into operation. The processing effects of the project were monitored and analyzed.The results show that the pollution control project of outfall runoff is efficient which decreases the pollution load including chemical oxygen demand COD total phosphorus TP suspended solids SS and ammonia-nitrogen NH3-N .As a result the water environment of the ancient canal is protected.

基于SWMM的LID设施空间格局优化模拟研究

为研究LID设施空间格局对径流控制和雨水径流污染负荷的影响,以雨水花园为例,采用SWMM构建的城市雨洪过程模型进行数值模拟,根据雨水花园在研究区汇水面上、中、下游区布设位置的不同来拟定优化方案,计算不同设计降雨重现期下雨水花园不同空间格局对径流调控和雨水径流污染负荷削减的提升效果。结果表明:(1)对于3种方案,径流总量控制率与设计降雨重现期呈负相关,将雨水花园布设在下游时,对径流总量控制率的提升效果最好;(2)在不同设计降雨重现期下,不同优化方案均对雨水径流污染负荷具有一定的调控效果,且雨水花园位于下游时对雨水径流污染负荷的净化效果最好,雨水花园对TSS和COD的削减效果整体要好于对NH_(3)-N和TP的削减效果。