人工湿地对氮、磷的去除效率与动态特征

Nitrogen and phosphorous removal efficiency and dynamic feature of constructed wetlands for sewage treatment.

1999年1月～2003年12月对荣成人工湿地污水处理系统处理效果以及氮、磷去除效果的动态变化特征进行分析.结果表明,人工湿地对SS、COD、BOD均有很好的去除效果,出水浓度分别为27.8±6.7、91.0±13.7和23.8±4.6 mg·L-1,去除率分别为71.8±8.4%、62.2±10.1%和70.4±9.6%.大肠菌群去除率为99.7%.对NH4+-N和TP去除效果较差,出水浓度分别为11.3±2.6和2.00±0.28 mg·L-1,去除率分别为40.6±15.3%和29.6±12.8%.NH4+-N去除效果和季节变化有关,每年7～9月去除效果最佳,1～3月效果最差,去除率分别为50.7±12.4%和23.0±11.6%.TP的去除效果季节性变化不如NH4+-N明显.NH4+-N年平均去除率2001～2003年逐年增加.TP年平均去除率在2001和2002年基本相同,2003年有所降低.

To evaluate pollutants removal efficiency and dynamic feature of nitrogen and phosphorous removal in a constructed wetland in Rongcheng,Shandong Province,water samples collected from Jan.1999 to Dec.2003 were analyzed.The results showed that the constructed wetlands could effectively reduce output of SS(suspended solids) by 71.8±8.4%,BOD(biological oxygen demand) by 70.4±9.6%,COD(chemical oxygen demand ) by 62.2±10.1%,and fecal coliform by 99.7%.However,the removal efficiency of nitrogen (406±153%) was relative low,and phosphorous (29.6±12.8%) had the least reduction efficiency.Nitrogen reductions displayed seasonal variations.The least efficient nitrogen reduction happened during Jan.to Mar.(23.0±11.6%),while the most efficient reduction happened during Jul.to Sept.(50.7±12.4%).Seasonal variation of phosphorous reductions was not as obvious as that of nitrogen.The nitrogen reduction efficiency increased from 2001 to 2003.Phosphorous reduction efficiency did not change on the whole from 2001 to 2002,but decreased a little in 2003.