Life-Cycle Assessment of an Industrial Recycling Process for Photovoltaic Panels Integrating Mechanical and Air-Assisted Pyrolysis Treatments

The rapid growth of photovoltaic (PV) installations has increased the need for the sustainable management of end-of-life PV modules. This study proposes an integrated mechanical and thermal recycling system for crystalline-silicon PV waste, combining mechanical pretreatment for dismantling and material separation with air-assisted pyrolysis in a tilting furnace to remove encapsulant and backsheet polymers. This system recovers electronic components, glass, silicon, aluminum, copper, and a liquid oil suitable for energy recovery. An industrial-scale system capable of treating 60 PV modules per hour was assessed through life-cycle assessment to quantify environmental impacts, identify hotspots, and compare two scenarios: mechanical recycling alone versus combined mechanical and thermal recycling. Results show that the integrated recycling system has the greatest impact on photochemical ozone formation, climate change, and the use of fossil resources. The results for these impact categories make the thermal section responsible for over 61.7% of the total environmental impact, primarily due to the emission of ethyne, ethylene, carbon dioxide, and methane. Nevertheless, the production of valuable byproducts is a clear environmental advantage that largely compensates for the impact created by the integrated recycling system. A comparative LCA also concluded that integrated recycling reduces 21.3% of the single score of the mechanical recycling alone, confirming the environmental superiority of our proposed system. Overall, this study supports circular-economy strategies in the PV sector by demonstrating the environmental advantages of combining mechanical and thermal processes for industrial PV recycling.