不同植物组合系统对微污染河水中氮磷的去除效果研究

A Study on Effects of Different Combined Plant Systems on Removal of Nitrogen and Phosphorus in Micro-Polluted River Water

通过在试验田构建小型表流人工湿地,比较了不同植物组合条件下表流人工湿地系统对弥苴河微污染河水中氮、磷的去除效果。结果显示,在夏季,3个湿地系统A、B、C对总氮平均去除率分别为74.8%、75.5%、70.6%,对总磷平均去除率分别为78.4%、79.3%、83.6%。随着植物枯萎和温度降低,去除效率降低但效果仍较理想,总氮和总磷的出水浓度分别保持在0.9、0.07 mg/L以下。夏季,系统B对总氮的去除效果好于系统A、C,这与B中植物长势好、稠密度高有关;3个系统对总磷去除效果区别不明显。为减少TN、TP释放,应定期清理湿地底泥和收割植物残体,以每年11月较为适宜。

Under different combined plant systems, the capacities of small surface-flow constructed wetland structured in the experimental field for removal of nitrogen and phosphorus in micro-polluted Miju River water were tested. It has shown that passing through three sets of wetland A, B and C, 74.8%,75.5%, 70.6% of total nitrogen and 78.4%, 79.3%, 83.6% of total phosphorus could be removed on average in the summer period, respectively. Along with the plants withered and temperature dropped,the removal efficiencies would descend but to a still fairly satisfactory treatment effect whilst the effluent strengths of total nitrogen and total phosphorus could be maintained at below 0.9 mg/L and 0.07 mg/L,respectively. In summer time, set B could run the best for total nitrogen removal due to its good way and denseness of plant growing, and however, there was no obvious difference in total phosphorus removal among those three sets of wetland. To lessen nitrogen and phosphorus release, dredging the sediment and taking the plant residues away from the wetland should be carried on regularly whilst November every year would be the ideal time.