Vermiremediation of cotton textile sludge by Eudrilus eugeniae: Insight into metal budgeting, chromium speciation, and humic substance interactions. (October 2020)

• Record Type: Journal Article
• Authors: Paul, Sarmistha; Goswami, Linee; Pegu, Ratul; Sundar Bhattacharya, Satya
• Is Part Of: Bioresource technology. Volume 314(2020)
• Publication Date: 2020-10
• Subjects: Textile waste -- Vermi-stabilization -- Chromium detoxification -- Metal removal; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2020.123753
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Vermicomposting removed ~50–70% toxic metals from cotton textile sludge (CTS) Budget equations were evolved to assess metal apportionments during biocomposting. Eudrilus eugeniae promoted transition of toxic Cr 6+ to benign Cr 3+. Humic acid and humin formation strongly induced Cr transition in vermibeds. Nutrients and pH were remarkably stabilized in CTS + CD vermibeds. Abstract: Information on prospective metal remediation by Eudrilus eugeniae during vermicomposting of cotton textile sludge (CTS) is rather scarce. This investigation, therefore, evaluates the sanitization efficiency of this species in CTS and CTS + cow-dung (CD) based feedstocks against aerobic composting. Accordingly, reduction in Pb, Cd, Cr, and Zn concentrations was between 50 and 70% under vermicomposting. Budget equations substantiated that humic compound mediated chelation was the dominant route of metal removal, against nominal bioaccumulation by earthworms. Correlation statistics revealed that formation of humic compounds (humic acid, fulvic acid, and humin) greatly influenced the transition of toxic Cr 6+ to benign Cr 3+ during vermicomposting. Moreover, increase in total N content and P availability was significantly greater under vermicomposting than composting. Thus, E. eugeniae efficiently stabilized the feedstocks by reducing pH, Ca, S, and organic C and CTS + CD(2:1) was the most favorable feedstock for E. eugeniae vermicomposting in respect of metal detoxification and nutrient stabilization.