The Research on the Effects of Substrate Types Using for Constructed Wetland

Abstract

In this study, pollutant removal effects of zeolite, ceramsite, quartz sand, and activated carbon were assessed its feasibility as a constructed wetland substrate using batch experiments. After 12 days of treatment, the removal rates of turbidity, surface color, true color, and chlorophyll of planktonic algae by 4~8 mm ceramic granules reached 93.6%, 92.1%, 89.7%, and 91.3%, respectively, which significantly improved the sensory effect of the landscape water. TN reached the class Ⅳ of the surface water, meanwhile, TP and permanganate index fulfilled the quality of the surface water class Ⅲ. After being treated by ceramsites, the UV 254 and UV 280 values, as well as CDOM absorption coefficients of the landscape water, were much lower, and the values of E 250 /E 365 were clearly higher than other substrates, which demonstrated excellent contaminant removal effect. All results indicated that 4~8 mm ceramsites were suitable substrates when used in CWs treating closed landscape water bodies. Long-term experiments should be carried out to test its pollutants removal performance in the future.