Life cycle assessment of different pre-treatment methods for silicon solar panel recycling

Under the wave of sustainable development, the number of solar panels installed has increased exponentially. The pretreatment process for recycling of c-Si PV can be divided into mechanical, chemical, and thermal treatment. In this study, a two-stage pyrolysis process was investigated as a pretreatment strategy to facilitate partial backsheet removal prior to high-temperature EVA decomposition. The Al electrode recovery rates were compared for traditional, two-stage, and microwave pyrolysis, with all methods achieving over 90% recovery. The LCA results indicated that laboratory-scale consumables strongly influenced the environmental performance of microwave pyrolysis, highlighting the need to distinguish equipment-specific burdens from intrinsic process characteristics. Two-stage pyrolysis can reduce emissions while ensuring the recycling quality of the solar cells. Key environmental concerns include energy use, consumables, and particle emissions from backsheet pyrolysis. Although this study is on a laboratory scale and lacking the use of real data and the discussion of backsheet pyrolysis gases it can be used as a reference for establishing a sustainable solar panel recycling process in the future. Because gaseous emissions were estimated using literature-based data rather than directly measured, the LCA results should be interpreted as a screening-level comparison of laboratory-scale pretreatment methods.