title: Life cycle assessment and residue leaching: the importance of parameter, scenario and leaching data selection.
abstract: Residues from industrial processes and waste management systems (WMSs) have been increasingly reutilised, leading to landfilling rate reductions and the optimisation of mineral resource utilisation in society. Life cycle assessment (LCA) is a holistic methodology allowing for the analysis of systems and products and can be applied to waste management systems to identify environmental benefits and critical aspects thereof. From an LCA perspective, residue utilisation provides benefits such as avoiding the production and depletion of primary materials, but it can lead to environmental burdens, due to the potential leaching of toxic substances. In waste LCA studies where residue utilisation is included, leaching has generally been neglected. In this study, municipal solid waste incineration bottom ash (MSWI BA) was used as a case study into three LCA scenarios having different system boundaries. The importance of data quality and parameter selection in the overall LCA results was evaluated, and an innovative method to assess metal transport into the environment was applied, in order to determine emissions to the soil and water compartments for use in an LCA. It was found that toxic impacts as a result of leaching were dominant in systems including only MSWI BA utilisation, while leaching appeared negligible in larger scenarios including the entire waste system. However, leaching could not be disregarded a priori, due to large uncertainties characterising other activities in the scenario (e.g. electricity production). Based on the analysis of relevant parameters relative to leaching, and on general results of the study, recommendations are provided regarding the use of leaching data in LCA studies.
authors.affiliation: Technical University of Denmark, Department of Environmental Engineering, Building 115, 2800 Lyngby, Denmark. Electronic address: elia@env.dtu.dk.
authors.forename: E
authors.initials: E
authors.lastname: Allegrini
authors.affiliation: Technical University of Denmark, Department of Environmental Engineering, Building 115, 2800 Lyngby, Denmark.
authors.forename: S
authors.initials: S
authors.lastname: Butera
authors.affiliation: Vanderbilt University, Department of Civil and Environmental Engineering, Box 1831 Station B, Nashville, TN 37235, USA.
authors.forename: D S
authors.initials: DS
authors.lastname: Kosson
authors.affiliation: Energy Research Centre of the Netherlands (ECN), Department of Environmental Risk Assessment, P.O. Box 1, 1755 ZG Petten, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Van Zomeren
authors.affiliation: Hans van der Sloot Consultancy, Dorpsstraat 216, 1721 BV Langedijk, Netherlands.
authors.forename: H A
authors.initials: HA
authors.lastname: Van der Sloot
authors.affiliation: Technical University of Denmark, Department of Environmental Engineering, Building 115, 2800 Lyngby, Denmark.
authors.forename: T F
authors.initials: TF
authors.lastname: Astrup
mesh_terms: D060729:Coal Ash / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis*; D017745:Incineration; D062611:Solid Waste / Q000032:analysis*
chemical_list: D060729:Coal Ash; D004785:Environmental Pollutants; D062611:Solid Waste
keywords: Bottom ash; LCA; Leaching; MSWI; Residues; Toxic impact