title: Impact of physical pre-treatment of source-sorted organic fraction of municipal solid waste on greenhouse-gas emissions and the economy in a Swedish anaerobic digestion system.
abstract: Several methods for physical pre-treatments of source sorted organic fraction of municipal solid waste (SSOFMSW) before for anaerobic digestion (AD) are available, with the common feature that they generate a homogeneous slurry for AD and a dry refuse fraction for incineration. The selection of efficient methods relies on improved understanding of how the pre-treatment impacts on the separation and on the slurry's AD. The aim of this study was to evaluate the impact of the performance of physical pre-treatment of SSOFMSW on greenhouse-gas (GHG) emissions and on the economy of an AD system including a biogas plant with supplementary systems for heat and power production in Sweden. Based on the performance of selected Swedish facilities, as well as chemical analyses and BMP tests of slurry and refuse, the computer-based evaluation tool ORWARE was improved as to accurately describe mass flows through the physical pre-treatment and anaerobic degradation. The environmental and economic performance of the evaluated system was influenced by the TS concentration in the slurry, as well as the distribution of incoming solids between slurry and refuse. The focus to improve the efficiency of these systems should primarily be directed towards minimising the water addition in the pre-treatment provided that this slurry can still be efficiently digested. Second, the amount of refuse should be minimised, while keeping a good quality of the slurry. Electricity use/generation has high impact on GHG emissions and the results of the study are sensitive to assumptions of marginal electricity and of electricity use in the pre-treatment.
authors: Waste Science & Technology, Luleå University of Technology, Luleå, Sweden; AnoxKaldnes AB, Klosterängsvägen 11A, 226 47 Lund, Sweden. Electronic address: my.carlsson@anoxkaldnes.com.
authors: My
authors: M
authors: Carlsson
authors: Profu AB, Mölndal, Sweden.
authors: David
authors: D
authors: Holmström
authors: NSR, North Western Scania Waste Management Company, Helsingborg, Sweden.
authors: Irene
authors: I
authors: Bohn
authors: Profu AB, Mölndal, Sweden.
authors: Mattias
authors: M
authors: Bisaillon
authors: AnoxKaldnes AB, Klosterängsvägen 11A, 226 47 Lund, Sweden.
authors: Fernando
authors: F
authors: Morgan-Sagastume
authors: Waste Science & Technology, Luleå University of Technology, Luleå, Sweden.
authors: Anders
authors: A
authors: Lagerkvist
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000693:Anaerobiosis; D019149:Bioreactors / Q000191:economics; D005740:Gases / Q000032:analysis; D017752:Greenhouse Effect; D012037:Refuse Disposal / Q000191:economics / Q000379:methods*; D062611:Solid Waste / Q000032:analysis*; D013548:Sweden
chemical_list: D000393:Air Pollutants; D005740:Gases; D062611:Solid Waste
keywords: Anaerobic digestion; Food waste; Life-cycle assessment; OFMSW; Pre-treatment; Systems analysis