Phytoremediation Potential of Duckweed (Lemna minor L.) On Steel Wastewater

Abstract

An eco-friendly and cost effective technique- phytoremediation was used to remediate contaminants from waste water. This study demonstrated that phytoremediation ability of duckweed (Lemna minor L.) to remove chloride, sulphate from Biological Oxygen Treatment (BOT) waste water of coke oven plant. The BOT water quality was assessed by analyzing physico-biochemical characters--pH, Biological oxygen demand (BOD), Chemical oxygen demand (COD), total dissolved solids (TDS) and elemental concentration. It was observed that an increase in pH value indicated an improvement of water quality. The experimental results showed that, duckweed effectively removed 30% chloride, 16% sulphate and 14% TDS from BOT waste water, which suggested its ability in phytoremediation for removal of chloride and sulphate from BOT waste water. A maximum increase of 30% relative growth rate of duckweed was achieved after 21 days of experiment. Thus, it was concluded that duckweed, an aquatic plant, can be considered for treatment of the effluent discharged from the coke oven plant.

Keywords: BOT water; Coke oven plant; duckweed; phytoremediation.