不同植物与水力负荷对人工湿地脱氮除磷的影响

Influence of different plants and hydraulic loading on the nitrogen and phosphorus removal of constructed wetlands

通过6种湿地植物的表流(SF)和潜流(SSF)人工湿地对比实验,分析了不同植物的SF和SSF人工湿地去除率随水力负荷(HL)变化的规律,得到了6种不同植物的SF和SSF人工湿地的最优HL、最优去除率.实验结果表明:6种植物的SF和SSF人工湿地对TP、TN去除率随HL的增加而降低,且植物不同,去除率降低趋势不同,且SSF人工湿地去除率降低值比SF小.SF人工湿地TP、TN去除率比SSF低,且TP去除率比TN大.SF人工湿地中水葱对TP、TN去除率降低最大,水芹菜对TP去除率降低最小,美人蕉对TN去除率降低最小;SSF人工湿地中美人蕉对TP去除率降低最大,水芹菜最小对TP去除率降低最小.芦苇对TN去除率降低最大,水葫芦对TN去除率降低最小.6种植物SF人工湿地去除TP和TN的平均最优HL分别为0.53,0.47t/(m2 d);SSF人工湿地去除TP、TN平均最优HL分别为0.68,0.44t/(m2 d).

Through the use of six kinds of surface flow （SF） and subsurface flow （SSF）constructed wetland plants in comparative experiments, the variation of hydraulic loading （HL） for the different plant constructed wetland of treatment rate was analyzed, and the optimal HL and removal rate of the 6 different plants in SF and SSF constructed wetland were got. Theoretical optimal HL, removal rate, the actual optimal HL and TP, TN removal in unit area of constructed wetland were calculated. The results show that TP, TN removal efficiency of the SF and SSF constructed wetlands with 6 plants increased with the decrease of HL, different plants, different levels of treatment. And the removal rate of SF constructed wetland were lower than SSF. The TP, TN removal rate of SF was lower than SSF and TP removal rate was higher than TN. In SF, the TP, TN removal rate of Scripus Validus reducing level was decreased maximum and the TP removal of Oenan the javan ica reducing level was decreased minimum, the TN removal rate of Canna ChinenesisW was decreased minimum. In SSF, the TP removal rate of Canna ChinenesisW reducing level was maximum, Oenan the javan ica reducing level was minimum and the TN removal rate of Phragmites Aust ralis was maximum, and Eichhornia crassipes was minimum. Meanwhile, the average optimal HL for TP removal of SF and SSF constructed wetland with the 6 kinds of plants were 0.53, 0.68t/（m2.d）, respectively. The average optimal HL for TN removal of SF and SSF constructed wetland with 6 kinds of plants were 0.47, 0.44t/（m2.d）, respectively.