Prioritization of Waste-to-Energy Technologies Associated with the Utilization of Food Waste

Abstract

Taking advantage of the growing production of organic waste for its conversion to waste-to-energy (WtE) also contributes to mitigating the problems associated with its final disposal, which is a global trend of increasing application. This work presents an innovative approach for the identification and prioritization of WtE alternatives available from the use of food waste (FW) present in the municipal solid waste (MSW) of a Colombian municipality with source separation and selective collection: (i) a systematic literature review, which allows one to identify WtE alternatives; (ii) the prospective MIC-MAC method (Matrice d’Impacts Croisés Multiplication Appliqués à un Classement) allowed the selection of criteria and sub criteria; (iii) the analytical hierarchical process (AHP) and the technique of order of preference by similarity to the ideal solution (TOPSIS), allowed a ranking of selected alternatives considering the technical, environmental, and social aspects. The WtE technologies identified were anaerobic digestion, gasification, incineration, biogas recovery from landfills, and pyrolysis; this last was excluded due to its greater application potential with substrates such as plastic waste. The six sub-criteria identified and prioritized were social acceptability (36%), greenhouse gas emissions mitigated (16.17%), MSW reduction (15.83%), energy production (13.80%), technological maturity (12.95%), and electrical energy conversion efficiency (5.25%), with the decreasing order of preferences of anaerobic digestion (78.2%), gasification (47.5%), incineration (27.4%), and biogas recovery from landfills (6.6%); the latter was the least desirable alternative (lower social acceptance and CO2 tons mitigated in relation to the other options). The innovative nature of this study is the identification and consideration of the comprehensive management of this type of waste of a large number of criteria (120 environmental, 52 social, and 59 technical) and the validation of the results through a sensitivity analysis, which allowed us to confirm for this study, that anaerobic digestion is the most favorable technology for the treatment and energy use of FW.