Life cycle assessment of end-of-life treatments of waste plastics in China

摘要

As the world's largest producer and consumer of plastics, China is also the largest producer and recycler of waste plastics. It is necessary to explore the environmental impacts of actual end-of-life (EOL) treatments of waste plastics in China. In this study, a life cycle assessment (LCA) was conducted to evaluate the environmental impacts of mechanical recycling of waste plastics as well as incineration and landfilling with municipal solid waste in China. The results indicate the environmental benefits of current EOL treatments of waste plastics in China. Mechanical recycling was a negative and decisive contributor, with a minimum impact on terrestrial acidification potential (-83.4%) and a maximum impact on global warming potential (-165.8%). Incineration had negative contributions to 8 of the 12 environmental indicators, and landfilling was a positive contributor to all environmental impacts. Scenarios of treatment pattern, recycling technologies and import policy were set to analyze the potential reduction in environmental impacts of future EOL treatments of waste plastics. Increasing the proportion of mechanical recycling would reduce all environmental impacts, including up to 51.8% on particulate matter formation potential. Energy conservation and emission reduction in atmospheric pollutants would effectively reduce the environmental impacts of mechanical recycling. Banning waste plastics imports would decrease the transportation distances of waste plastics, thereby reducing the related environmental impacts, most notably a reduction of 84.8% for marine ecotoxicity potential. This study provides robust references for waste plastics management in China.