人工湿地处理滨海盐碱地区初期雨水和微污染河水

Integrated Constructed Wetland for Treatment of Initial Rainwater and Micro-polluted River Water in Coastal Saline-alkali Area

在天津生态城蓟运河故道河边选用砾石、钢渣、沸石及沙子作为填料,以耐盐植物菖蒲为植被,构建了5 760 m^2的复合流人工湿地,考察对滨海盐碱地区初期雨水和微污染河水中COD、总氮和总磷的去除效能。对系统运行数据的分析表明:不同运行条件下,该系统对初期雨水中的污染物均有着良好的去除效果和抗冲击负荷能力。经复合人工湿地处理后,对初期雨水中COD、TN和TP的去除率分别为(86.5%~90.1%)、(85.8%~91.2%)和(84.6%~90.0%)。非汛期时,该人工湿地系统可用于净化微污染河水,对微污染河水中COD、TN和TP的最大去除率分别为86.7%、93.2%和88.9%,实现了削减河水中的污染物和保持生态系统稳定的双重功能。

A 5 760 m2 integrated constructed wetland （ICW） was built using gravel, slag, zeolite and sand as the carriers, and salt-tolerant plant Acorus calamus as the vegetation at the old course of Jiyun River near Tianjin Eco-city. The removal of COD, TN and TP from initial rainwater and micro-pol- luted river in coastal saline-alkali area was investigated. The analysis on the operation data showed that the system had good removal effect and anti-shock loading capacity for pollutants in the initial rainwater under different operating conditions. The removal rates of COD, TN and TP in the initial rainwater were 86.5% to 90.1%, 85.8% to 91.2% and 84.6% to 90.0% respectively. In the non-flood season, the ICW could be used for purification of micro-polluted fiver water. The maximum removal rates of COD, TN and TP were 86.7%, 93.2% and 88.9% respectively. The ICW could reduce pollutants in the fiver and maintain the stability of eco-system at the same time.