Impact of Eisenia fetida populations on bio-conversion of paper mill solid wastes

Abstract

Purpose Huge quantity of paper mill wastes are dumped at the outskirt of factory as unwanted materials. Vermicomposting is an eco-friendly technique for beneficial conversion of different biodegradable/organic wastes into useful organic manure utilizing earthworms. Solid wastes generated in paper mills contain appreciable quantity of organic matter. Attempt was made for bio-conversion of Emami paper mill wastes with different numbers of Eisenia fetida (5-30 earthworms/2 kg substrate) for studying its influence on vermi-conversing time and quality of prepared vermicompost. Method Vermicomposting was carried out in trays following heap method and quality of final product was determined following both chemical analysis and bioassay on wheat seedlings. Results Application of more earthworms up to 20 numbers per 2 kg substrate made bio-conversion quicker but further addition of earthworm, however, delayed the process as some earthworms came out of beds and died probably due to competition for food among earthworms inside beds. Ten earthworms per kg paper mill wastes-saw dust-cow dung mixture (1:0.5:0.5 weight wise) was found as optimum earthworm population for preparing quality vermicompost having more major and secondary plant nutrients. Bioassay of this manure on wheat seedlings also confirmed the analytical findings. Conclusion It is confirmed that earthworm population in vermibed played vital role in faster decomposition of paper mill wastes and releasing of more nutrients, which ultimately helped in better growth of wheat seedlings. Successful demonstration of vermicomposting technique will encourage local farmers for beneficial utilization of paper mill wastes in their agriculture.

Vermicomposting of harvested waste biomass of potato crop employing Eisenia fetida: changes in nutrient profile and assessment of the maturity of the end products

“…The vermicompost production was recorded 47.33% from PPB and 54.11% from PPB+CD mixture indicating signi cant enhancement in the outputs after the addition of CD. This result agrees with the previous ndings of Mohapatra et al (2019) who have reported about 39-54% vermicompost production during vermicomposting of paper mill sludge. Several factors are associated with vermicompost production which includes types, initial population, reproductive and metabolic activities of the earthworms; physicochemical, nutrients composition and amount of resource materials and time duration of experimental periods (Sharma and Garg 2018).…”

“…The Na contents have decreased signi cantly in the nal products and are found in the range of 90.85-110.85 mg/kg and 50.5-60.52 mg/kg in the compost and vermicompost samples respectively. The decrease in Na content in the vermicompost samples has been reported by the previous worker (Mohapatra et al 2019) which can be attributed to the absorption of Na by earthworms, besides, the possibility of Na volatilization due to activity of microbes and earthworms during vermicomposting cannot be ignored.…”