Eunomia study identifies limited need for advanced plastic sorting

A report published by Eunomia has examined the role of advanced sorting technologies in increasing plastic packaging circularity in Europe. The study, which focused on household-like waste streams in the EU, Norway, Switzerland, and the United Kingdom, found that existing sorting technologies are sufficient for sorting most plastic packaging.

Andy Grant, Technical Director and the project's lead at Eunomia said: "With increased interest in marker-based solutions for sorting plastic packaging, the findings of this report should be timely for decision-making across Europe and Member States.

“This report concludes that the application of advanced sorting technologies is not likely to be necessary to facilitate circular recycling across many packaging formats because existing technology is sufficient. Where advanced sorting is necessary, we already see some examples; in some rigid plastics formats, object recognition is already delivering tangible results. In flexible formats, further work is needed to determine which of the advanced formats may be necessary."

The research, Advanced Sorting for Circularity, identified that advanced sorting is primarily needed for contact-sensitive applications in HDPE and PP containers, representing approximately 11 per cent of rigid plastic packaging. These materials require more precise sorting to meet safety standards for recycled content in food, skin-care, and pharmaceutical packaging. The report notes that for food contact approvals in Europe, mechanical recyclers will likely need to ensure that their feedstock is at least 95 per cent previously food contact material.

Three advanced technologies were evaluated in detail: Object Recognition (OR), chemical markers, and digital watermarks. Among these, OR emerged as the most cost-effective solution for sorting rigid plastics. The study found that OR can be implemented more quickly and on a plant-by-plant basis, unlike marker-based technologies which would require EU-wide agreements.

Cost analysis revealed that the installation and operation of sorting machinery represent a relatively small fraction of the total cost of effectively managing a targeted material stream. The larger portion of costs are associated with the application of markers and licensing of systems to identify them. This gives OR a significant cost advantage, as it doesn't require marker systems or additional printing costs.

For HDPE and PP rigids, the report provides detailed cost breakdowns. OR was found to be the most economical option in terms of cost per tonne of material sorted, with digital watermarks being the most expensive.

The report also highlights uncertainties regarding the need for and effectiveness of advanced sorting for flexible plastics. Researchers noted that further investigation is needed to determine the role of advanced sorting in achieving circularity for these materials.

The study found that existing sorting technology, with further optimisation and some minor design for recycling improvements, will be able to sort material to produce mono PP and mono PE grades from flexible plastics. According to the report: "Optimisation of existing technology which would mainly involve a relatively straightforward update of spectral libraries and some design for recycling changes could result in DSD-323 type grades being adequately sorted into mono material grades and [Multi-Material Multi-Layer] grades, excepting a small number of cases that can be considered marginal issues which are unlikely to cause circularity issues."

Traceability in the plastic recycling supply chain is currently poor in Europe. Advanced sorting technologies could potentially improve this situation by providing more detailed information about the origin and composition of plastic waste. However, the high costs involved raise questions about the economic feasibility of implementing such systems. The study suggests that achieving a reasonable degree of traceability would produce substantially more cost than sorting for circularity.

For traceability purposes, OR technology appears to be more cost-effective than digital markers. The report estimates that the annual cost for applying digital markers across all plastic packaging once in the supply chain ranges from €196m to €217m, compared to €48m to €50m for OR. OR works by using artificial intelligence to identify materials based on their visual characteristics, potentially providing classification of brands at Stock-Keeping Unit (SKU) level through the recognition of brand icons and label text. However, the report notes that this is likely to be limited for films and flexibles where branding is less prevalent on packaging.

Regarding overall recycling rates, the report states: "The key to increasing the quantity and quality of plastic packaging recycled and thereby increasing the plastic packaging recycling rates is not to modify classification machines with advanced sorting techniques, but to increase the amount of plastic packaging collected and optimisation of existing sorting technology." It notes that the main barriers to increased recycling are collection rates and market demand for recycled materials, rather than sorting capabilities.

In light of the proposed Packaging and Packaging Waste Regulation (PPWR), the study suggests that these advanced sorting technologies might be crucial in meeting future recycled content targets, particularly for contact-sensitive applications. The PPWR sets specific recycled content targets for different types of plastic packaging, ranging from 30 per cent to 65 per cent by 2040.

The study suggests that advanced sorting technologies might be crucial in meeting future recycled content targets, particularly for contact-sensitive applications.

The proposed Packaging and Packaging Waste Regulation (PPWR) sets specific recycled content targets for different types of plastic packaging in the EU, ranging from 30 per cent to 65 per cent by 2040. Similarly, the UK has introduced the Plastic Packaging Tax, placing a charge on items that don’t contain at least 30 per cent recycled plastic. These regulations aim to increase the use of recycled content in plastic packaging, potentially driving demand for more precise sorting technologies.

Furthermore, the introduction of Extended Producer Responsibility (EPR) for packaging in various countries, including plans for modulated fees based on recyclability and recycled content, may provide additional incentives for improved sorting and recycling processes.