Life Cycle Assessment of a Hybrid Sorting Approach for Post-Consumer Lightweight Packaging Waste

Abstract This study conducts a life cycle assessment of a hybrid sorting approach for post-consumer lightweight packaging, combining near-infrared spectroscopy, color recognition, AI-based image analysis, tracer technology, and optional digital watermark identification. Four scenarios combine conventional and advanced sorting with mechanical and chemical recycling via pyrolysis. The Environmental Footprint 3.1 method is applied across ten impact categories and shows notable improvements over the current sorting and recycling state. Per megagram (Mg) of lightweight packaging collected and recycled, net greenhouse gas emissions are reduced by up to 416 kg CO₂-eq, fossil energy demand decreases by up to 9 GJ, and water scarcity impacts are reduced by over 111 m³ world-eq. Further improvements are observed in categories such as carcinogenic toxicity and particulate matter-related health impacts. These findings underline the environmental advantages of integrating advanced sorting and complementary recycling technologies. The yield of plastic recyclates increases from 276 kg to up to 480 kg per Mg of input waste, reducing environmental burdens and simultaneously improving resource efficiency. This increased output directly contributes to higher plastic recycling rates, which are crucial for achieving policy-driven circular economy targets. The results emphasize that upgrading sorting and recycling infrastructures is an effective strategy to minimize environmental impacts while enhancing circularity in plastic packaging systems.