Pilot scale study on phosphorus removal from malodorous water body by pumice vertical flow constructed wetlands

Aquatic plants(Pontederia cordata) and packing material(pumice) were chosen to construct vertical flow constructed wetlands(VFCW) which have functions of both landscaping and purification of malodorous water body.The pilot study on phosphorus removal from malodorous water body by pumice VFCW was conducted successfully.The concentration of total phosphorus(TP) in influent and effluent of VFCW were detected at different times.The results show that removal rate of TP ranged 58.13%~83.25% and the changing trend of TP removal rate is in accordance with that of temperature.The TP removal effect varies with time and space: In case of short experimental runs(less than 2 months),the surface(less than 20 cm thick) of pumice displays stronger removal effect of phosphorus than other depths;in case of more than 2 months,the removal effects of phosphorus have small variations in different depths.Study on the correlation between ferric iron and phosphorus in the depth of 20 cm by SPSS V13.0 shows Pearson correlation coefficient r=-0.692,P=0.0180.05,which indicates a negative correlation between the concentrations of ferric iron and the phosphorus.