Transitioning from Coincineration to Multipath Thermochemical Energy Conversion: Environmental and Economic Decision-Making for Recycling Screened Lightweight Oversized Waste from Aged Refuse

Enormous screened lightweight oversized waste (SLW) from landfills, consisting of plastics, textiles, and rubber, is overlooked for thermochemical conversion due to the coincineration’s advantage of utilizing existing infrastructure. This study compares the environmental and economic performance of three emerging SLW pathways with coincineration using integrated hybrid life cycle assessment and techno-economic analysis. Results show that combined pyrolysis and incineration pathways with secondary classification provided environmental and economic advantages over coincineration and copyrolysis with mixed wastes. However, persistent conflicts emerge in technology selection: while ethylene production (S3) delivers superior environmental performance, it requires extended investment recovery compared to oil production (S4), which offers balanced environmental-economic benefits; coincineration (S1) achieves the shortest payback period through existing infrastructure but provides limited environmental advantages. These findings reposition landfilled waste from chronic urban stressors to subsurface resource reservoirs. However, policymakers should select context-appropriate SLW reutilization technologies based on local infrastructure and prioritized policy objectives.