Sustainability, design for recycling, digitalisation, and circularity are the new buzzwords in the packaging industry. Upcoming legislative targets in the EU require – among others – that packaging placed on the market be recyclable by design by 2030, and include recycled content. Such obligations represent a significant incentive for companies to transform their business, and invest in innovative technologies.
The HolyGrail 2.0 Initiative is a great example of cross-value chain collaboration as the key to achieving these targets. Driven by AIM, European Brands Association and powered by the Alliance to End Plastic Waste, this consortium of over 120 companies and organisations aims to revolutionise packaging waste sorting through digital watermarks, while emphasising innovation and industry’s commitment.
What are digital watermarks?
They are imperceptible codes, the size of a postage stamp, covering the packaging surface and carrying a wide range of attributes. Once the packaging has entered into a waste sorting facility, the watermark can be detected and decoded by a high-resolution camera on the sorting line, which then – based on the transferred attributes (e.g. food vs. non-food) – is able to sort the packaging in corresponding streams. This would result in better and more accurate sorting streams, thus consequently in higher-quality recyclates.
From proof of concept to industrial trials
The Initiative is divided into three phases, with Phases 1 and 2 on prototype development and semi-industrial validation respectively completed in 2021 and 2022. The results confirmed that digital watermarks enable more accurate sorting of packaging waste than current technologies, creating separate recycling streams, such as for food, cosmetics, or detergents applications.
In Phase 3, the prototypes have been deployed in commercial plants to further test the technology, this time under standard industrial conditions. Trials at a recycling plant in France demonstrated the digital watermarks effectiveness in separating food and non-food PET waste streams, a critical step towards achieving EFSA guidelines.
Earlier this year, an additional set of trials was conducted in a material-recovery facility in Germany, to assess the technology’s sorting capability on flexible packaging from a mixed waste stream. The overall sorting results enabled the creation of new higher-quality recycling streams – food-grade PP flexibles and hygiene-grade PE flexibles – at efficiency rates not possible with other technologies.
At the same site, a three-month trial is starting to sort post-consumer digitally watermarked rigid packaging introduced to the Danish and German markets by various HG2.0 member companies. If successful, the technology will be further validated in industrial setting, reaching TRL 9 – system proven in operational environment.
In parallel, HolyGrail 2.0 has partnered with GS1 in Europe to create an open, interoperable architecture using the GTIN as the identifier. This system will facilitate safe and efficient data sharing among stakeholders, defining clear roles and responsibilities. The architecture aims to boost innovation and competition by being accessible to all relevant parties.
Advanced sorting is a key enabler to unlocking high-quality recycling, and a strategic choice to enable food-grade sorting/recycling. But there is more to it: through the creation of smart packaging, the digital watermarks technology also has the potential to be used in other areas such as consumer engagement, supply chain visibility and retail operations, making it an important driver towards a substantial packaging value chain transformation.