How advanced sorting can contribute to plastic circularity in Europe

The report, entitled Advanced Sorting for Circularity, published today, finds that for many plastic packaging formats, further optimisation of existing sorting technologies is likely to be sufficient for improved circularity. For the remaining sorting challenges, object recognition could be the most cost-effective advanced sorting technology to facilitate increased circularity, including when compared to marker technology.

The plastic packaging industry is currently facing a growing demand for increased sustainability, particularly in increasing recycled content and fostering a circular economy. This pressure varies across Europe but is predominantly driven by public and governmental demands, leading to brand owners adopting more sustainable practices. EU legislation also enacts requirements around packaging, particularly the anticipated Packaging and Packaging Waste Regulation (PPWR), expected to go into effect later in 2024.

This new report explores how marker and object recognition sorting technologies can contribute to circularity and traceability in plastic packaging recycling, specifically within the EU, Norway, Switzerland, and the UK.

The report’s methodology involves identifying polymers and packaging material formats not adequately sorted by existing technologies for achieving circularity. It then evaluates new technologies (i.e., advanced sorting technologies) that could enable classification and sorting of these post-consumer plastic packaging types. A range of new sensor- and marker-based sorting technologies are also examined. Three are shortlisted for detailed cost and performance modelling: object recognition, chemical markers, and digital watermarks.

The study focuses on sorting solutions that provide a suitable feedstock for mechanical recycling processes, which in turn produces material suitable for packaging manufacturers. This focus is due to the underlying assumption that the potential for circular recycling using mechanical processes should be explored before defaulting to chemical recycling processes.

Nuanced understanding will be essential

Findings of the study cover insights into the circularity for rigid and flexible plastic applications, traceability and implementation. These findings provide a clear direction for targeted investment and innovation in sorting technologies, emphasising the importance of aligning technological choices with specific recycling objectives and the unique requirements of different packaging types. As the industry moves towards meeting EU recycled content targets, this nuanced understanding will be essential in guiding efforts towards more effective and sustainable plastic packaging recycling practices.

The analysis concluded that advanced sorting is necessary for only a limited set of issues affecting circularity. For rigid plastics, this pertains to contact sensitive applications in HDPE and PP, where current sorting solutions fall short of achieving circularity. For flexibles, advanced sorting is not necessary for producing recyclate grades but might be required to achieve contact-sensitive grades for mechanical recycling, pending further evidence on performance. As the focus of advanced sorting as modelled is increasing circularity in a waste stream which is already collected and sorted for recycling using existing technologies, implementing advanced sorting in this way will not significantly boost overall recycling rates for either rigid or flexible plastics.

All advanced sorting technologies could offer increased traceability, though it is reasonable to conclude that this would be greater with digital markers than with object recognition. However, traceability would require significantly more investment than is needed to achieve greater circularity and, in the case of markers, it would require far more packages being marked. Whether there is a willingness to pay for increased traceability remains uncertain.

It seems highly likely that object recognition can be (and arguably is being) adopted far more quickly than the marker technologies.

The report concludes that it seems likely that there will be continued adoption of object recognition technologies, and these may offer a more cost-effective solution for circularity. Both the plastics industry and policy developers should consider whether using marker technologies as a mass market solution offers sufficient additional benefits to warrant both the additional cost and the complex implementation process.