不同径流条件下钱塘江突发性水污染事故影响的预测模拟

Forecast and simulation of influence of emergency water pollution accident occurred in Qiantang River under different runoff conditions

采用二维潮流水质模型对钱塘江河口突发性水污染事故对水质的影响进行了模拟预测。分析结果表明:随着上游径流流量加大,污水团输移的速度明显加快,最大浓度也有所降低。同时随着污染物在输移过程中稀释扩散,超标总历时沿程逐渐增大,污染物最大浓度沿程逐渐降低。模拟及计算结果显示:突发污染事故后,加大上游的下泄流量,对加快污染团下移、稀释污染团从而降低污染物浓度的作用非常明显,模拟结果可为处理突发性水污染事故提供提供重要的理论依据。

The 2-D tide water quality model was adopted to simulate and forecast the impact of emergency water pollution accident occurred in Qiantang River on water quality. The result showed that the transport velocity of polluted water distinctly increased with the increase of runoff and the maximum concentration also decreased. In the same time, with the dispersion and dilution of pollution in the process of transport, the total duration increase and the maximum concentration decreased gradually along the river. The result of simulation and calculation revealed that the increase of discharged flow at the upstream of river plays a very important role in accelerating the polluted water to move downward and diluting the pollutant body so as to lower the pollutant concentration when the emergency water pollution accident occurred. The result can provide an important theoretical basis for the treatment of unexpected water pollution emergency.