潮汐河流排污口设置对水质的影响

Influence of setup of drain outlet for tidal river on water quality

以扬州市青山污水处理厂长江排污口的设置为例,根据潮汐河流的水动力、污染物输移特征,采用正交曲线网格离散计算区域,采用有限体积法离散控制方程,建立了非稳态平面二维水动力、水质数学模型,采用90%保证率下的枯水设计径流量与大潮、小潮典型潮位过程的组合作为设计水文条件,模拟分析了典型水文条件下,污水排放对纳污水体水环境的影响,旨在为排污口设置提供技术依据。

According to the hydrological and pollutant transport characteristics of tidal rivers,a 2-D unsteady water quality mathematical model was established by means of discretization of the computing region with the orthogonal curvilinear grid and discretization of the control equation with the finite volume method.A case study was conducted on the setup of the drain outlet of the Yangtze River at Qingshan Sewage Treatment Plant in Yangzhou City.The designed hydrological condition considered the combination of the low flow at a 90% guarantee rate and the typical courses of spring tide and neap tide.Under these typical hydrological conditions,the influence of pollutant drainage on the Yangtze River was simulated,providing a technical basis for the setup of drain outlets.