title: Experimental and life cycle assessment analysis of gas emission from mechanically-biologically pretreated waste in a landfill with energy recovery.
abstract: The global gaseous emissions produced by landfilling the Mechanically Sorted Organic Fraction (MSOF) with different weeks of Mechanical Biological Treatment (MBT) was evaluated for an existing waste management system. One MBT facility and a landfill with internal combustion engines fuelled by the landfill gas for electrical energy production operate in the waste management system considered. An experimental apparatus was used to simulate 0, 4, 8 and 16weeks of aerobic stabilization and the consequent biogas potential (Nl/kg) of a large sample of MSOF withdrawn from the full-scale MBT. Stabilization achieved by the waste was evaluated by dynamic oxygen uptake and fermentation tests. Good correlation coefficients (R(2)), ranging from 0.7668 to 0.9772, were found between oxygen uptake, fermentation and anaerobic test values. On the basis of the results of several anaerobic tests, the methane production rate k (year(-1)) was evaluated. k ranged from 0.436 to 0.308year(-1) and the bio-methane potential from 37 to 12Nm(3)/tonne, respectively, for the MSOF with 0 and 16weeks of treatment. Energy recovery from landfill gas ranged from about 11 to 90kWh per tonne of disposed MSOF depending on the different scenario investigated. Life cycle analysis showed that the scenario with 0weeks of pre-treatment has the highest weighted global impact even if opposite results were obtained with respect to the single impact criteria. MSOF pre-treatment periods longer than 4weeks showed rather negligible variation in the global impact of system emissions.
authors.affiliation: Dipartimento di Ingegneria Industriale, Via G. Duranti 67, 06125 Perugia, Italy. Electronic address: francesco.dimaria@unipg.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Di Maria
authors.forename: Alessio
authors.initials: A
authors.lastname: Sordi
authors.forename: Caterina
authors.initials: C
authors.lastname: Micale
mesh_terms: D000332:Aerobiosis; D056804:Biofuels / Q000032:analysis*; D005740:Gases / Q000032:analysis; D008697:Methane / Q000032:analysis*; D018505:Waste Management
chemical_list: D056804:Biofuels; D005740:Gases; D008697:Methane
keywords: Anaerobic test; Energy recovery; Landfill gas generation; Life cycle assessment; Mechanical Biological Treatment; Oxygen uptake