Removal of Metals from the Refinery Wastewater through Vertical Flow Constructed Wetlands

A series of experiments was carried out to assess the viability of treating refinery wastewater using coarse sand for the removal of heavy metals. Typha lattifolia was planted in two containers to evaluate the treatment efficiencies of vertical flow constructed wetlands. The results demonstrated low treatment efficiency of constructed wetlands during the initial stage but with the growth of plants and bio-film improved gradually. Vertical flow constructed wetland filled with coarse sand was operated for treatment of refinery wastewater at hydraulic loading rate of 1.21, 1.44 and 1.71 m3/m2day-1, at regular intervals. The results showed high removal efficiencies for iron (Fe) (49%), copper (Cu) (53%) and zinc (Zn) (59%) in the coarse sand filled wetlands. The coarse sand filled constructed wetland showed good treatment performance at hydraulic loading rate of 1.21 m3/m2day-1. It is concluded that that constructed wetland can be used as economical option for wastewater quality enhancement in developing countries. © 2010 Friends Science Publishers