Application of a vetiver system for unconventional water treatment

摘要

In this research, a pilot phytoremediation experiment was conducted to evaluate the effectiveness of vetiver grass (Vetiveria zizanioides L. Nash) in the uptake of contaminants from two unconventional water samples. The vetiver was hydroponically planted in two unconventional water samples taken from a mine (W-1) and saline groundwater taken from wells located around the mine area (W-2). Although waters from the Golgohar mining site are not permitted to escape into public waters and the aim of the current research was to examine the efficiency of the vetiver system in the reusage of water for ore processing plant, this study just focused on salinity and thus the total dissolved solids (TDS), electrical conductivity (EC), total hardness (TH), anions (SO4, Cl) and cations (Na, K, Mg, Ca) were considered and analysed. The results indicated that all five elements were distributed more in the shoots than in the roots of the vetiver, particularly Na, K and Ca, as seen from the average concentration ratios of 74.7, 42, 55.9 43 and 60.2% for Na, Cl, Ca, Mg and K, respectively. The weed grown in W-2 with the upper plant growth had the highest SO4, Na, K, Ca, Cl and Mg removal efficiencies of 70.9, 59.1, 58.4, 51.5, 48.7 and 23.8%, respectively, whereas the weed grown in W-1 showed efficiency of up to 43.6% Mg removal from the water samples. The results showed that treatment efficiencies of total hardness, TDS and EC of water samples were equal to 46, 31.5 and 28.3% for mine wastewater and 45.1, 33 and 28% for groundwater in the fourth week, respectively.