Reduction of pollution load of paper mill effluent by phytoremediation technique using water caltrop (Trapa natans L.)

Abstract

Laboratory experiments were conducted to investigate the reduction of pollution load of paper mill effluent through phytoremediation technique using water caltrop (Trapa natans). Different concentrations, viz. 0% (control), 25, 50, 75, and 100% (absolute) were treated using T. natans for 60 days. Results showed that sewage effluent was loaded with various parameters, viz. total dissolved solids (TDS), electrical conductivity, total Kjeldhal nitrogen (TKN), phosphate ((Formula presented.)), calcium (Ca2+), magnesium (Mg2+), potassium (K+), cadmium (Cd), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), and zinc (Zn). The maximum removal of different parameters was recorded after 60 days of phytoremediation experiments. Water caltrop (T. natans) significantly (p < 0.05/p < 0.01) removed TDS, BOD, COD, TKN, (Formula presented.), Ca2+, Mg2+ and K+, Cd, Cu, Fe, Ni, Pb, and Zn of the paper mill effluent after the phytoremediation. The removal of different pollutants from the paper mill effluent was gradually increased at lower concentration i.e. (from 20 to 50%) concentrations of the paper mill effluent. The maximum fresh weight, dry weight, and LAI of T. natans were observed with 50% concentration of the paper mill effluent at 45 days of phytoremediation experiments. Therefore, T. natans can be used for the treatment of paper mill effluent up to 50% concentration for 60 days using phytoremediation technique.