Case study: Sustainability assessment of viable techniques toward municipal organic solid waste upcycling and carbon reduction.

The ongoing growth of Organic Fraction of Municipal Solid Waste (OFMSW) and its disposal processes has intensified resource pressure. Building on the entropy-weighted method, this study integrates material flow, life cycle assessment, and carbon footprint methodologies to develop a multi-dimensional evaluation framework that comprehensively considers the synergies across carbon emissions, economic, environmental impacts, and policy dimensions. Four OFMSW disposal scenarios for the Suzhou Industrial Park case in China were developed based on current standard practices and potential future reference systems. Quantitative analysis of two viable technical portfolios at various levels, along with sustainability assessments of their emission reduction potential, indicates that the circular economy pattern (Scenarios S3 and S4)-which shifts OFMSW toward biomass resource recovery and upcycling-is feasible. The decarbonization strategy S4, combining internal heat recovery and hydrothermal carbonization, yielded favorable outcome. Compared to current practices, processing each ton of OFMSW could reduce CO2e emissions by 0.24 tons, which is projected to offset over 0.4% of China's annual CO2 emissions by 2030. Overall, these findings provide support for developing OFMSW management strategies oriented toward sustainable economy development.