基于水动力水质模型的金川河流域水质长效达标分析

Analysis of Long-term Water Quality up to the Standard in Jinchuan River Basin Based on Hydrodynamic and Water Quality Model

为解决金川河流域水质全年不能稳定达标的现状,在对金川河流域污染特征分析的基础上,考虑流域污水处理厂处理能力、补水能力、截污能力提升,拟定了3种长效达标方案,对各方案水质提升效果进行预测分析。结果表明:现状污染源条件下,在流域污水处理厂提质增效10%,以及在此基础上增加50%流域补水量两种方案中,虽氨氮浓度峰值有所下降但浓度仍高于Ⅴ类水标准;在以南方污水处理厂考核目标进水浓度方案中,流域入河污染负荷总量降低约44.4%左右,河网氨氮浓度则明显降低,其中下游考核断面宝塔桥断面氨氮浓度降至1.85 mg/L,其水质全过程基本能够满足水质长效达标的效果。计算结果可为金川河流域水污染治理与防控提供有效的科学依据。

The water quality of the Jinchuan River Basin cannot reach the standard steadily all year round.Thus,after analyzing the pollution characteristics of the basin,this paper proposes three schemes for water quality that can reach the standard in the long term,considering the improvement in the treatment,water supplement,and sewage interception abilities in sewage treatment plans of this basin.Meanwhile,prediction and analysis are also conducted on the water quality improvement effects of each plan.The results are as follows.In current pollution source conditions,regarding the two schemes where sewage treatment efficiency is increased by 10%and the basin water supplement rises by 50%on this basis,the peak concentration of ammonia nitrogen decreases,whereas the concentration is still higher than the Class V water standard.In the third scheme where the inflow concentration can achieve the assessment objectives of a south sewage treatment plant,the pollution load of pollutants into the river is reduced by about 44.4%.Therefore,the ammonia nitrogen concentration in the river network is significantly decreased,and the ammonia nitrogen concentration in the Baotaqiao section of downstream is reduced to 1.85 mg/L.Its water quality can meet the long-term water quality up to the standard in the whole process.The results can provide an effective scientific basis for water pollution control and prevention in the Jinchuan River Basin.