三种类型人工湿地在非点源污染中的治理效果

TREATMENT EFFICIENCY OF NON-POINT SOURCE POLLUTIONS IN THREE TYPES OF CONSTRUCTED WETLANDS

采用垂直流、水平潜流和复合型人工湿地系统,对珠海市斗门镇上洲村农村生活污水进行处理并进行污染物削减效果对比。研究发现:3种湿地对COD和NH+4-N的去除率分别达66%~77%和96%~97%,去除效果较好且不存在显著差异。复合型和水平潜流湿地对TN(92%)和TP(66%~75%)去除效果相当,但显著大于垂直流(<50%)。不同湿地对污染物去除率呈现秋季>夏季的趋势,但季节间差异不显著。除了TP和垂直流湿地的TN,不同湿地出水浓度均达到地表水质III^II类标准。总体上,复合型和水平潜流湿地较垂直流具有较好的污染物去除能力,适合在农村水环境治理中推广应用。

The performances and differences of removal efficiencies on pollutants from rural domestic sewage were investigated by three kinds of constructed wetlands（ i. e. horizontal-flow constructed wetland,vertical-flow constructed wetland,and integrated horizontal-vertical wetland） in Shangzhou Village,Zhuhai City. The results showed that removal efficiencies of COD and NH＋4-N by three constructed wetlands were high without significant differences,and the average removal rate were 66% -77% and 96% - 97%,respectively. The average removal rates of TN（ 92%） and TP（ 66% - 75%） in integrated horizontal-vertical wetlands were almost equivalent with those in horizontal-flow wetlands,but significantly higher than those in vertical-flow wetlands（ 〈50%）（ P〈0. 05）. The average removal efficiencies of pollutants in autumn were better than in summer,but there were no significances between seasons in most cases. The concentrations of all pollutants except TP and partial TN in treated effluent from three kinds of constructed wetlands could reach Grade III to II standard of surface water in China. In totally,integrated horizontal-vertical flow wetlands and horizontal flow wetlands were better than vertical flow wetlands in removal efficiencies of pollutants,which could be promoted in rural polluted water treatments.