How does future decarbonization in industries affect the climate benefits of plastic recycling? A market share-based model for the avoided burden approach of life cycle assessment

In the life cycle assessment (LCA) of recycling, the estimation of avoided burdens influences environmental benefits. This study formulated a model for the avoided burden approach in LCA that uses the market share of relevant materials and energy to take the impact of future decarbonization in the industry into account. The model was applied to a case study on recycling and recovery options for plastic packaging in Japan. The results showed that, as decarbonization progressed in the relevant industries, environmental benefits on climate change impacts were substantially affected for chemical recycling through gasification (ammonia production) and energy recovery (solid fuel production and use) but only marginally affected for mechanical recycling. It was suggested that recycling and recovery options that could provide secondary materials or energy for industries whose production processes would be reliant on fossil-derived materials be prioritized during the transition phase to a decarbonized society.