Life cycle assessment of post-industrial plastics mechanical recycling. A case study from Italy

Plastics produce significant environmental impacts related to their production and disposal processes. About 40 % of plastics are thrown away within a month either in landfills or in the environment, causing effects on ecosystems and human health. Therefore, proper management of plastic waste is a particularly significant issue. Thus, this research aims to evaluate the environmental sustainability of mechanical recycling of post-industrial PE-LD, choosing an Italian company as a case study. The results show how mechanical recycling of PE-LD could particularly affect global warming, with 152 kg CO₂ eq/1000 kg PE-LD, Ionizing radiation, with 14.65 kBq of Co-60 eq, Ecoterrestrial toxicity, with 13.04 kg of 1,4-DCB eq, Land Use, with 30.57 m²a eq and Fossil Resource Scarcity, with 42.19 kg of oil eq., mainly due to the high energy intensity of the process. However, producing mechanically recycled plastics could reduce impacts in all impact categories from -64 % to -97 %, compared to virgin plastics. Furthermore, for the same input material, mechanical recycling could be between 7 and 366 times more sustainable than other forms of chemical recycling. Finally, the excessive energy expenditure of the process could be partially solved by the installation of photovoltaic panels, which would provide benefits in 12 out of 18 impact categories. Therefore, the results of this study show how mechanical recycling could adequately replace end-of-life plastics in landfills and avoid the production of new fossil polymers, generating significant environmental benefits, and greatly helping the sector.