Pioneering Digital Watermarks takes significant steps towards circular economy goals

The HolyGrail project is leading-edge work - driven by AIM, the European Brands Association and powered by the Alliance To End Plastic Waste - that has brought together brand owners, retailers, recyclers, packaging producers and sorting technology providers from across the plastics value chain to investigate ways to improve the sorting of post-consumer plastics.

After successfully developing a basic proof of concept around the promising technology of digital watermarks, HolyGrail 2.0 has been conducting semi-industrial testing mimicking real-life conditions of the prototype detection unit for digital watermarks.

Now, after eight months of analysis of the Pellenc ST/Digimarc prototype at the Amager Resource Center in Copenhagen, the project has achieved a significant milestone. Results show that the digital watermark technology can achieve more granular sorting of packaging waste at scale, such as developing separate food and other new Post-Consumer Resin (PCR) streams that currently do not exist, for example for cosmetic or detergent applications.

In May 2022, another semi-industrial test with the second HolyGrail 2.0 detection sorting prototype unit, developed by the machine vendor Tomra and the digital watermarks technology supplier Digimarc, also achieved impressive results. Based on these two tests, both prototype machines are now ready for industrial-scale pilots. This would open new recycling streams, effectively overcoming the limitations of current near-infrared (NIR) sorting technologies, driving a true circular economy for packaging. Consistently high results across all tested categories of plastic packaging material showed 99% detection, 95% ejection and 95% purity rates on average, demonstrating the impressive performance of these first prototypes.

“At Milliken we believe this is a great initiative that will be a giant leap forward towards achieving recycling goals, contributing to the European Green New Deal to make the EU’s economy sustainable by 2050,” said Wim Van de Velde, Milliken’s Global Vice President Plastic Additives. “Credit goes to everyone across the value chain who helped HolyGrail 2.0 get to this point, and we look forward to the next, larger steps,” he continued. 

On the back of this success, Phase 3, planned to start in 2023, will conduct full-scale validation and industrial tests, consumer engagement and distribution tracking. The HolyGrail 2.0 prototype will be deployed under standard operation conditions in both France and Germany, in one Materials Recovery Facility (MRF), one Plastics Recovery Facility (PRF) and two recycling plants.

Brand owners and retailers will be bringing their enhanced products commercially to market in Denmark, France and Germany where consumers will be able to buy on-shelf products with digitally watermarked packaging, which will enter the waste stream after consumption. These full-scale tests will be examining the system’s reliability to ensure optimum performance.

The MRF will test and capture all digital watermarked rigid packaging from Germany and Denmark with committed commercial enhanced samples from brand owners and retailers standing at 38-thousand tons per year. The PRF will receive input from the Materials Recovery Facility as well as ongoing supply and spiked volumes with a focus on granular sorting. The two recycling facilities will center on end-to-end recycling to non-food rPET bottle grade and food rPP film grade.

Additional tests may take place throughout 2023. Looking ahead, AIM and the Alliance to End Plastic Waste are already in discussions to put together a long-term vision for the next stage of the project, HolyGrail 3.0. This would include a strategy to scale the technology in Europe and beyond.

“The HolyGrail project is an excellent example of how engaged and committed businesses coming together around a very clear goal can accelerate the development of new solutions. We are one step closer to making intelligent waste sorting a reality through digital watermarks,” concluded Jacob Duer, President and CEO of the Alliance to End Plastic Waste.