Keywords: food processing waste, FPW, vermicomposting, Eisenia fetida, dewatered sludge, cow dung, pulp and paper mills, nitrogen, phosphorous, cocoon production, earthworm biomass, oxygen uptake rate
Vermicomposting of dewatered sludge from pulp and paper mill
The present paper is aimed at conversion of dewatered sludge from pulp and paper mill into value added product through vermicomposting. The dewatered sludge was blended with cow dung and food processing waste in five different combinations R1 (1.5), R2 (1 + 0.24 + 0.26), R3 (1 + 0.34 + 0.16), R4 (1 + 0.41 + 0.09) and R5 (1 + 0.46 + 0.04) for utilisation in vermicomposting using Eisenia fetida. The earthworms have enriched the end product with high nitrogen profile as confirmed by many fold increase in total nitrogen (TN) and also in total phosphorous (TP), and available phosphorous (AP). Oxygen uptake rate (OUR) reduced by 5–11 folds in all the reactors after 45 days of vermicomposting. Cocoon production and the earthworm biomass increased as vermicomposting progressed. However, R3 (1 + 0.34 + 0.16) proved to be best combination for the growth and hatchlings of the earthworms. On an overall basis R4 proved to be the best feed combination for vermicomposting followed by R5, R3 and R2 respectively.