Multi-Criteria Analysis and Consequential Lifecycle Assessment of Solid Waste Management

Abstract

Based on a case study comparing different approaches for management of organic waste generated in the city of Rio de Janeiro, Brazil, this study proposes the combination of consequential lifecycle assessment (CLCA) and multicriteria decision analysis (MCDA). Compared approaches were landfilling with energy recovery from landfill gas, source segregation of organics for anaerobic digestion and use of digestate as fertilizer, and finally, post-sorting of organics and landfilling of residual bio-solids. Seven different impact categories were assessed in the CLCA. In addition, recovery of electricity and macro nutrients were included as additional impact categories. The use of VIP analysis facilitates the interpretation of results aggregating them under different conditions. Furthermore, approaches for ranking of considered impact categories could be carried out both for a local or a global perspective. This, and the possibility of easily including additional context derived evaluation parameters, clearly highlights the combination of CLCA and VIP analysis for decision support.