Life Cycle Assessment and Multi-criteria Decision Analysis: Selection of a strategy for domestic food waste management in Rio de Janeiro

Results from Life Cycle Assessment (LCA) of solid waste management are, in many cases, difficult to interpret because there is no entirely satisfying alternative. Therefore, most of the studies focus on a small number of environmental impact categories. While this might facilitate the interpretation of the results, it also creates a risk of excluding relevant aspects from the assessment. For instance, the limited impact-coverage of Carbon footprint calculations where exclusively climate change related greenhouse gas emissions are considered. On the other hand, the inclusion of a larger number of impact categories in the study creates a risk of conflicting results. Multi-criteria Decision Analysis (MCDA) is a powerful approach for decision aiding, where highly diversified indicators can be analysed in the same framework helping to organise the available information and identify pros and cons in the decision process as well as its aggregation. This paper aims at improving decision making in solid waste management by combining LCA and MCDA techniques harmonically, using management of food waste from households in the city of Rio de Janeiro as a case study. Oriented to support decisions in choice problems, the software VIP-Analysis was used to choose the best food waste treatment option among the results of the LCA conducted. The VIP-Analysis is perfectly applicable in aggregating the LCA results due to its ability to handle problems with impreciseinformation, improving the decision making process.