Phytoremediation of pulp and paper mill and distillery effluents by channel grass (Vallisneria spiralis)

The phytoremediation of the effluents of pulp and paper mill and distillery employing channel grass is assessed in terms of reduction in pH, EC, BOD, COD, TSS, TS, TDS, colour, lignin, Na and K. The effluents are treated at two different concentrations, viz. 20 and 40 per cent for 45d. The effect of effluents on the channel grass health is also monitored. In general the phytoremediation by channel grass results in significant reduction in all the selected parametres of pulp and paper mill and distillery effluents over '0' d value, except that of pH. Treatment by channel grass results into maximum. reduction in COD of pulp and paper mill effluent (74.66 per cent) and in colour unit of distillery effluent (75.19 per cent), whilst the minimum reduction is observed in sodium content of the two effluents at 20 per cent concentration (31.84 and 38.77 per cent). Per plant leaf number, and leaf area increases up to 124 per cent and chlorophyll a, chlorophyll b, total chlorophyll and total carbohydrate are increased up to 34.38, 51.85, 39.56 and 48.64 per cent, respectively, in pulp and paper mill effluent at 20 per cent concentration, whilst in 20 per cent distillery effluent plants shows the corresponding increase by 113.75, 113.80, 25.0, 37.04, 28.57 and 40.54 per cent, respectively. In general, pollution load reduction and plant growth are found to be better in 20 than in 40 per cent concentration of effluents.