Life cycle assessment of reduce, recycling and final treatment of plastic primary food packaging in Norway using a system expansion with multiple functions scope

Abstract Purpose Extended methods and more representative datasets are needed to comprehensively evaluate the environmental life cycle performance of recycling systems compared to other material strategies. In this paper, we investigate the environmental impact profile of recycling compared to reduction, linear systems (energy recovery or landfill) and a change in the plastic polymer used in primary food packaging in a southeastern Norwegian context. Method The life cycle assessment scope is a system expansion with multiple functions (SEMF), which accounts for every function through a cascade of recycling loops. Closed-loop allocation is used to compare the average burden of a product within a recycling loop cascade to the reduce and linear system strategies. The regionalised scope is set to southeastern Norway, for which regionalised life cycle inventories are collected. Low and high recycling scenarios were investigated. Low recycling scenarios represent current open-loop recycling efficiencies per studied polymer type, whilst high recycling scenarios are derived from the Norwegian Deposits Pay System (DPS) PANT of beverage bottles. The energy recovery rate is based on the country mixes in which the plastics are incinerated. The investigated plastic polymers are mono-polyethylene terephthalate (mono-PET) and 95% low-density polyethylene (LDPE) with 5% ethylene vinyl alcohol (EVOH). Results and discussion The current open-loop recycling of polyethylene terephthalate (PET) and polyethylene (PE) film in Norway is comparable to a linear product system with energy recovery and landfill across all environmental impact categories. The high - efficiency recycling system demonstrated the potential to achieve 50% less climate impact compared to the linear baseline, but with great impact variability across the investigated environmental indicators and multiple instances of problem-shifting. Comparatively, a 50% reduction in material thickness corresponded to a universal 50% lower impact compared to the linear baseline across all impact categories. The SEMF framework highlights the resource and environmental limitations of current and potential recycling efficiencies, which are otherwise missed at the product level. Conclusion Material recycling has no significant environmental benefit compared to a linear reference with the current recycling rates. Much higher recycling rates are needed, but material quality degradation is an obstacle. The factual numbers of recycling loops due to material degradation and losses should be included in life cycle assessments (LCAs) to provide a more realistic picture of the environmental performance of material recycling. The study also showed that the reduction of material and a change of material resulted in lower environmental impact, which underscores the need to combine different strategies.