Is multi-source solid waste co-disposal practices in waste-to-energy plants sustainable???A comparative life cycle assessment

Multi-source solid waste co-incineration in waste-to-energy plants with excess capacity offers a promising symbiotic model, though its environmental impact and resource sustainability are uncertain, especially related to other disposal methods. This study evaluates for co-disposal scenarios of multi-source waste (food waste, municipal sludge, medical waste, and industrial waste) using life cycle analysis and comparing with ten traditional disposal methods. Results show co-disposal achieves over 95 % waste reduction, with energy recovery rates from 27.6 % to 63.3 %. Food waste co-disposal exhibits environmental benefits, while municipal sludge co-disposal shows impacts across all environmental indicators. Medical and industrial waste co-disposal produces significant fossil CO2 emissions but mitigates other environmental impacts. From an economic perspective, co-disposal shows IRRs from 16.8 % to over 2000 %, reducing waste disposal fees by 23.7 % to 90.5 %. This study recommends co-disposal as a supplementary approach, advocating for clearer industry standards, aligned regional planning, and refined operational practices to enhance sustainability. © 2024 Elsevier B.V.