Effects of Interior Electrolytic Substrates Fe-Cu Ratio and Hydraulic Retention Time on Pollutant Removal Efficiency of Constructed Wetlands

To investigate effects of interior electrolytic substrates Fe-Cu ratio and hydraulic retention time (HRT) on pollutant removal efficiencies of constructed wetlands, an experiment was carried out using surface flow constructed wetland beds different in interior electrolytic substrates Fe-Cu mass ratios (1∶0, 1∶0.05, 1∶0.1 and 1∶0.2) and in hydraulic retention time (1, 2, 3, 4 and 5 h). Data of the experiment were analyzed using two-way analysis of variance (ANOVA) with Fe-Cu interior electrolytic and HRT as two factors. Results show that TP removal efficiency of the bed varied sharply with Fe-Cu ratio, but COD_Cr and TN removal efficiencies did not. Pollutant removal efficiencies varied with hydraulic retention time, too, and the longer the HRT, the higher the pollutant removal efficiency. However, no significant effect of interactions between Fe-Cu interior electrolytic and hydraulic retention time was observed.