LCA OF WASTE MANAGEMENT SYSTEMS Reliability-based life cycle assessment for future solid waste management alternatives in Portugal Ana Pires & Ni-Bin Chang & Graça Martinho Received: 2 August 2010 / Accepted: 19 February 2011 / Published online: 24 March 2011 # Springer-Verlag 2011 Abstract Background, aim, and scope This paper presents a study related to the application of the reliability-based life cycle assessment (LCA) to assess different alternatives for solid waste management in the Setúbal peninsula, Portugal. The current system includes waste collection, transport, sorting, recycling, and mechanical and biological treatment (MBT) by means of aerobic treatment and landfill. In addition, some future expansion plans are discussed. Materials and methods The proposed 18 alternatives were examined with respect to six impact categories based on a customized life cycle inventory (LCI). All the alternatives are designed to comply with the targets prescribed in the Packaging and Packaging Waste Directive and the Landfill Directive. These 18 alternatives were eventually assessed by using the reliability-based LCA methodology with respect to some uncertain parameters and scenarios. Results and discussion The results show that solutions based on anaerobic digestion at the MBT followed by energy recovery are the most advantageous options. Overall, recycling may help to avoid most environmental impacts. Alternatives which treat massively biodegradable municipal waste are also competitive. In addition to the recycling options, electricity production is also an influential determinant which affects the results. The uncertainty analysis focused on testing different energy-from-waste options (like landfill and MBT biogas electricity production) and different recycling substitution ratios. Such a quantitative analysis is proved effective to confirm the reliability of the LCI in the study. Conclusions In order to improve the sustainability of the solid waste management (SWM) system, final suggestions may concentrate on the closure of aerobic MBT, the enhancement of anaerobic digestion MBT treatment, and the maximization of energy recovery from high calorific fractions of the waste streams. However, the option of stabilized residue applica- tions cannot be encouraged at this stage, especially due to the absence of Portuguese regulations to control the quality of organic products issuing from biological treatment units. Keywords LCA . MBT . Municipal solid waste management system . RDF . Uncertainty analysis 1 Introduction Life cycle assessment (LCA) is an important tool comple- menting other systems analyses for sustainable develop- ment in an urban region. To achieve the sustainability goals, however, the long-established cost-effectiveness approach is becoming obsolete whereas cost–benefit anal- ysis may also have to be revised in the future. It is believed that LCA-based planning techniques in concert with cost– benefit information may lead to an insightful assessment of sustainable solutions for solid waste management (SWM). Applications of LCA techniques to SWM systems in Europe started in the 1990s of the last century. The first case of its kind took place for assessing the management of waste beverage packaging systems in Denmark. This pioneering work aimed to determine the best solutions for Responsible editor: Shabbir Gheewala A. Pires (*) : G. Martinho Departamento de Ciências e Engenharia do Ambiente, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal e-mail: alp11931@fct.unl.pt N.-B. Chang Department of Civil, Environmental, and Construction Engineering, University of Central Florida, 4000 Central Florida Blvd., Orlando, FL 32816, USA Int J Life Cycle Assess (2011) 16:316–337 DOI 10.1007/s11367-011-0269-7