Vermiconversion of industrial sludge for recycling the nutrients

The aim of the present study was to investigate the transformation of sugar mill sludge (PM) amended with biogas plant slurry (BPS) into vermicompost employing an epigeic earthworm Eisenia fetida. To achieve the objectives experiments were conducted for 13 weeks under controlled environmental conditions. In all the waste mixtures, a decrease in pH, TOC, TK and C:N ratio, but increase in TKN and TP was recorded. Maximum worm biomass and growth rate was attained in 20% PM containing waste mixture. It was inferred from the study that addition of 30–50% of PM with BPS had no adverse effect on the fertilizer value of the vermicompost as well as growth of E. fetida. The results indicated that vermicomposting can be an alternate technology for the management and nutrient recovery from press mud if mixed with bulking agent in appropriate quantities.