基质组配、填充方式及水力负荷对生态滤坝净化效果的影响

Effects of substrate combination,packing arrangement and hydraulic loading on the purification performance of ecological filter dam

为提升生态滤坝净化能力,选取砾石、沸石、陶粒、蛭石4种基质,进行基质组配、填充方式及水力负荷等多情景下的污染物(COD、氨氮、总磷)去除效果试验。试验结果表明:砾石+陶粒组配方式去除COD效果最好,而去除氨氮和总磷效果最好的组配方式是砾石+沸石;砾石和沸石均匀混合有利于COD的去除,而砾石在前沸石在后的填充方式是去除氨氮和总磷最高效的填充方式;随着水力负荷的增大,3种填充方式下COD和总磷的去除率均呈现递减趋势,均匀混合填充方式下氨氮的去除率呈现递减趋势而分层填充方式下氨氮的去除率呈现先增大后减小趋势。

This study tested the contaminant removal effect under the conditions of substrate combination,packing arrangement,and hydraulic loading under four substrates(gravel,zeolite,ceramsite and vermiculite)as part of an attempt to improve the purification capacity of ecological filter dams.The results showed that the gravel and ceramsite group had the superior COD removal efficiency,whereas the best removal efficiencies of NH^(+)_(4)-N and TP were achieved by the gravel and zeolite group.It was also found that uniform mixing mode could most effectively improve the removal of COD,but the best removal efficiencies of NH^(+)_(4)-N and TP were found in the gravel in former and zeolite in behind mode.With the increase of hydraulic loading,the removal rates of COD and TP in three mixing modes were gradually decreased,and NH^(+)_(4)-N removal behaved decrease in uniform mixing mode,but increased first and then decreased in two-layer mixing modes.