Assessment of a combined dry anaerobic digestion and post-composting treatment facility for source-separated organic household waste, using material and substance flow analysis and life cycle inventory. (August 2017)

• Record Type: Journal Article
• Authors: Jensen, Morten Bang; Møller, Jacob; Scheutz, Charlotte
• Is Part Of: Waste management. Volume 66(2017)
• Page Start: 23
• Page End: 35
• Publication Date: 2017-08
• Subjects: Life cycle inventory -- Food waste -- Compost -- Mass balance -- Mass flows -- Substance transfer coefficients -- Emissions; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2017.03.029
• Languages: English
• ISSNs: 0956-053X

Abstract

Highlights: MFA and SFA of a combined dry anaerobic digestion and post-composting facility is presented. All metals ended up in compost or residues, but concentrations complied with legislation. 23% of the carbon content of the organic waste was transferred to the biogas and 24% to the compost. 69% of the nitrogen was transferred to the compost. A complete life cycle inventory was conducted. Abstract: The fate of total solids, volatile solids, total organic carbon, fossil carbon, biogenic carbon and 17 substances (As, Ca, CaCO3, Cd, Cl, Cr, Cu, H, Hg, K, Mg, N, Ni, O, P, Pb, S, Zn) in a combined dry anaerobic digestion and post-composting facility were assessed. Mass balances showed good results with low uncertainties for non-volatile substances, while balances for nitrogen, carbon, volatile solids and total organic carbon showed larger but reasonable uncertainties, due to volatilisation and emissions into the air. Material and substance flow analyses were performed in order to obtain transfer coefficients for a combined dry anaerobic digestion and post-composting facility. All metals passed through the facility and ended up in compost or residues, but all concentrations of metals in the compost complied with legislation. About 23% of the carbon content of the organic waste was transferred to the biogas, 24% to the compost, 13% to residues and 40% into the atmosphere. For nitrogen, 69% was transferred to the compost, 10% volatilised to the biofilter, 11% directly into the atmosphere and 10% to residues. Finally, a full life cycle inventory was conducted for the combined dry anaerobic digestion and post-composting facility, including waste received, fuel consumption, energy use, gaseous emissions, products, energy production and chemical composition of the compost produced.