LCA Modeling of Waste Management Scenarios

Lifecycle assessment (LCA) modeling provides a quantitative statement about resource issues and environmental issues in waste management useful in evaluating alternative management systems and in mapping where major loads and savings take place within existing systems. Chapter 3.1 describes the concepts behind LCA modeling and Chapter 3.2 gives an overview of existing models and shows examples of their application. A recent comprehensive review of publicly available LCA studies (WRAP, 2006) concluded that, on a material basis, LCA modeling in general confirms the validity of the waste hierarchy and shows that recycling is superior to incineration with energy recovery, which again is better than landfilling. Cleary (2010) reviewed 20 waste management scenarios assessed in 11 studies published in the period 2002–2008 and concluded that, due to lack of transparency regarding boundary conditions and exchange with the energy systems, a comparison of results was hampered on a system level. In addition, differences in waste composition may affect the LCA results. This chapter provides results of LCA modeling of 40 waste management scenarios handling the same municipal waste (MSW) and using different combinations of waste recycling, biological treatment, incineration, mechanical–biological treatment and landfilling. The purpose is to compare waste management on a system level and to indentify the steps and treatments within the system contributing the most to the environmental performance of waste management systems. The study focuses on Europe in terms of waste composition and exchange with the energy system. The waste management systems modeled are described with respect to waste composition, waste management technologies, mass flows and energy exchange in the systems. Results are first presented with respect to Global Warming contributions (kg of CO2-eq./t of waste). These data are identical to those presented in Christensen et al. (2009). Finally also results for other impact categories are presented.