Environmental Performance of Applying Alternative Energies to the Collection, Transport and MBT Plant Within an Integrated MSW Management System

Abstract

This study extends the environmental assessment of Municipal Solid Waste (MSW) management strategies using Life Cycle Assessment (LCA) methodology with the objective of evaluating the environmental implications of applying alternative energies to the collection, transport and operation of a Mechanical–Biological Treatment (MBT) plant within an integrated MSW management system. To this end, the environmental implications of the use of alternative energies in two stages of the MSW management system were taken into account: (1) collection and transportation systems for the residual household waste of MSW; and (2) the MBT plant operation including the recovery of its residual fraction. As a case study, the MSW management system of the Ecocity Valdespartera and the MBT plant in Zaragoza have been evaluated. These sites are located in the Autonomous Community of Aragon (Spain). In this study, different scenarios of alternative energy supply from renewable energy sources were evaluated at each stage of the management system. Impact assessment for each of the scenarios considered the following six impact categories: (1) acidification (kg SO2 eq.); (2) global warming (100 years) (kg CO2 eq.); (3) eutrophication (kg PO4 eq.); (4) photochemical oxidation (kg C2H4 eq.); (5) abiotic depletion (kg Sb eq.); and (6) ozone layer depletion (kg CFC-11 eq.). These categories are contained in the CML 2 baseline 2,000 impact assessment method V2.05. The software Simapro V. 7.3.2 was also used. Results show that when alternative energy supply scenarios from renewable energy sources (RES) are included in both the collection system and the operation of the MBT, environmental benefits can be achieved in comparison to current state of affairs. In this scenario, the avoided emissions are greater than those generated in most of the impact categories under study. The results identify scientific and technical processes that can be used to promote fundamental changes in the management of upstream flows of MSW in MBT plants and in its operation.