闸控感潮河段重金属迁移转化规律研究

以长江感潮江段的某入江河道为典型案例,根据闸控条件下的水文特征、污染物迁移转化特性分别建立了由入江河道及长江相关河段构成的动态二维水动力及重金属数学模型,模拟分析了闸门控制下入江河道的水流运动规律、点源连续排放的重金属浓度随时间变化及二维平面分布特征。模拟结果表明:在长江潮汐、水闸控制影响下,入江河道内重金属浓度在一定范围内呈现周期性波动的现象,重金属浓度整体呈增大趋势,随着污水排放时间的推移,河道内各断面处重金属浓度最大值和波动区间均趋于稳定;典型超周期内,河道内落潮流污染带长度大于涨潮流。重金属在潮汐河道内的变化是一个非常复杂的过程,对这一过程的模拟,可以为河道水质治理和污染防治提供技术依据。

Study on rule of heavy metal transport and transformation in tidal section of river controlled by gate

Taking one tributary of tidal reach of the Yangtze river as typical example, according to the hydrological and pollutant transport characteristics of tidal rivers controlled by gate,the paper established a two dimensional dynamic hydrodynamic and mathematical model of heavy metals, simulated and analyzed the hydrodynamic rule of the tributary of the Yangtze river in the control of gate, and time varying characteristics and two-dimensional plane distribution of the concentration of heavy metal in the tributary with discharge of point source continuous.The simulation results show that under the influence of the tide and gate of the Yangtze river, the concentration of heavy metal in the tributary appears cyclical fluctuations in a certain range and with the trend of increase.Along with the elapse of sewage discharge time,The maximum concentration and fluctuation interval of heavy metals in river tends to be stable;in a typical super cycle,the spatial distribution of polluted area at low tide is more than that at high tide. The variation of heavy metals in tidal river is a very complex process.The simulation for this process can provide a technical basis for the management of river water quality and the prevention of pollution.