摘要:Present work provides an opportunity to utilize the potential to bioconversion and recovering nutrients from thermal power plant fly ash with the help of earthworm Eisenia fetida. The fly ash (FA) was mixed with cattle dung (CD) with and without earthworms at different proportions 0:100, 25:75, 50:50, 75:25 and 100:0. In all these proportions changes in physico-chemical properties and population growth of earthworms were observed. Minimum mortality and maximum population buildup of earthworm were observed in 25:75 mixture. Vermistabilization caused decrease in pH (8.0% to 15.7%), electrical conductivity (16.2% to 53.6%), total organic carbon (15.6% to 32.5%) and C:N ratio (43.2% to 97.4%). A significant range of increase in total potassium (6.2% to 58.9%), total available phosphate (33.0% to 53.2%) and total nitrogen (43.4% to 92.7%) was observed after conversion by earthworms. Reduction of heavy metals Cu (24.6% to 45.9%), Pb (28.8% to 38.3%), Mn (19.3% to 35.4%) and Cr (15.7% to 40.0%) was also observed at variable range in the end products of feed mixtures with earthworms. Earthworms increase the plant available nutrients and mitigate the metal toxicity in the fly ash. Vermiconversion might be useful in efficient management of hazardous solid waste produced from thermal power plants.
关键词:Thermal power plant; Fly ash; Vermistabilization; Heavy metals; Eisenia fedida