不同水力负荷下两类湿地脱氮效果对比研究

Comparative Study on Nitrogen Removal by Two Kind of Constructed Wetlands under Different HRT

在不同水力负荷下,对比研究了复合垂直流人工湿地和潜流人工湿地对污水处理厂二级出水的脱氮效果。结果表明,复合垂直流人工湿地系统对NH_4^+-N的去除能力显著高于潜流人工湿地系统(P<0.05),但是两类湿地系统对TN的去除能力差异并不显著(P>0.05)。水力负荷越低,两类湿地系统对NH_4^+-N、TN去除率的差距越明显。以脱氮为主要目标时,复合垂直流人工湿地系统最佳的水力负荷为0.6~0.8 m/d,潜流人工湿地系统水力负荷可取低值0.4~0.6 m/d。

A simulation experiment was carried out to compare the nitrogen removal effect of integrated vertical flow con- structed wetland （IVCW） and subsurface flow constructed wetland （SSFW） on secondary effluent from wastewater treatment plants under different hydraulic loading. The results showed that the removal effects of NH4^＋-N by IVCW were better than SSFW （P〈0.05）, but the removal ability of TN by the two kinds of wetlands had no significant difference （P〉0.05）.In addition,the lower the HLR was,the more obvious the removal capacity difference for NH4^＋-N and TN by the two kinds of wetlands was.Taken nitrogen removal as the main object, the best hydraulic loading for IVCW was between 0.6-0.8 m/d,t while for SSFW was a lower value between 0.4-0.6 m/d.