人工湿地-沉水植物塘组合系统治理村镇污染水体

Treatment of rural polluted river water by combined system of constructed wetlands with submerged macrophyte pond

采用人工湿地-沉水植物塘组合系统在不同水力负荷(200、500、1 000mm/d)条件下对村镇污染水体净化效果进行研究。结果表明:在不同水力负荷和污染负荷下,组合系统整体运行稳定、耐负荷能力强、去除效果良好;出水COD达到《地表水环境质量标准》(GB 3838—2002)的Ⅲ类标准,出水总磷达到GB 3838—2002的Ⅴ类标准,出水总氮达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)的一级A标准,出水氨氮达到GB 18918—2002的一级B标准。除溶解性正磷酸盐以外,组合系统对污染物的去除效果均随着水力负荷的增加整体呈现出下降趋势,低水力负荷去除效果最优。沉水植物塘在氮、磷去除效果上优于人工湿地,而人工湿地在COD去除效果上则优于沉水植物塘。

The pilot scale combination system of constructed wetlands combined with submerged macrophyte pond was adopted for treatment of rural polluted river water. This combination system was operated under different hydraulic loading of 200,500,1 000 mm/d,and its purification efficiency was examined. Results showed that the com bination system had many features of running stable under different hydraulic loading and pollution loading, stronger ability for resisting shock load, and perfect performance for pollutant removal. The effluent COD could meet ill class criteria of environment quality standards for surface water （GB 38382002）, TP reached the V class criteria of GB 38382002~The effluent TN and NH3N was respectively satisfy the first grade A standard and first grade B standard of discharge standard of pollutants for municipal wastewater treatment plant （GB 189182002）. With increasing the hydraulic load of combination system,the removal efficiency of pollutants showed an overall weakening trend except soluble phosphate. The submerged macrophyte pond was better than wetland on the nitrogen and phosphorus remov al, while wetland presented more excellent properties for COD removal.