基于片区水环境容量的吴江区污水处理系统优化布局

Layout Optimization of Wastewater Treatment System Based on Water Environmental Capacity in Wujiang District

在污染源计算和控制单元划分的基础上,核算了苏州市吴江片区内部各个控制单元的水环境容量,并在此基础上对重点排污单元的污水处理系统进行了优化布局。通过将吴江片区划分为29个控制单元,计算得到其COD_(Cr)、氨氮和TP的水环境容量分别为91 594.91、3 527.62 t/a和476.66 t/a,其中,浦南片区的平望镇和盛泽镇污染负荷超标严重。根据污染源现状分析得到吴江片区主要污染来源为城镇生活源、工业点源和城镇径流面源。通过对污水厂布局调查研究发现,现状污水厂布局散乱,超负荷运行现象普遍。依据水环境容量计算值,对平望浦南区域和盛泽镇污水厂进行优化布局,使得其COD_(Cr)和氨氮入河量均不超过水环境容量,同时建议加强农田面源污染、城镇径流污染等面源污染管控,促进吴江片区水环境质量改善。

Based on the calculation of pollution load and division of control unit,water environmental capacity of each control unit of Wujiang District in Suzhou was calculated and the layout of wastewater treatment system of the main pollutant-emission unit was optimized.This paper divided Wujiang District into 29 control units and then the water environmental capacity was calculated,which for CODCr,ammonia nitrogen and TP were 91594.91,3527.62 t/a and 476.66 t/a,respectively.According to the pollution load analysis,it indicated that the main pollution sources were residential waste,industrial production and urban runoff non-point pollution.In addition,based on the research of current WWTPs,it showed that the WWTPs were scattered and most of them were currently in overload operation.Owing to the result of water environmental capacity,this paper ameliorated the layout of WWTPs in the south bank area of Taipu River in Pingwang Town and Shengze Town,which made the pollution load of CODCr and ammonia nitrogen not exceed water environmental capacity.It is also suggested that the control measures of non-point source pollution,such as farmland pollution and urban runoff pollution,should be strengthened,in order to improve the water environmental quality of Wujiang District.