Digital watermarking initiative partners to boost food container recycling

15 Jul 2024 --- As global waste management systems face structural challenges, European brands are calling for a transformation of the plastics value chain. The digital watermarking initiative “HolyGrail 2.0” aims to prove the viability of digital watermarking technologies for accurate sorting and the business case at large scale. 

HolyGrail 2.0 is a consortium of over 120 companies and organizations from the packaging value chain. 

One of the initiative’s workstreams, involving FiliGrade Sustainable Watermarks, Alpla, Farm Dairy and Pellenc ST, is now engaged in a new project aimed at testing the capability of FiliGrade Sustainable Watermarks’ CurvCode watermarking technology to close the loop on HDPE milk bottles in the Netherlands.

Packaging Insights sits down with Margherita Trombetti, project manager and policy officer for Sustainability at the European Brands Association, AIM, and Marien De Lint, a member of the executive board at FiliGrade Sustainable Watermarks, to discuss the importance of digitalization in packaging waste management. We also talk about how the initiative can help the industry meet regulations under the Packaging and Packaging Waste Regulation (PPWR).

Can you introduce CurvCode watermarking technology? 
De Lint: The CurvCode digital watermark developed by FiliGrade is a patented code enabling high-speed granular sorting required for high-quality recycling. FiliGrade provides digital encoding and detection technologies for enhancing physical products with digital markers. Not only can products carrying CurvCode be sorted based on material characteristics, but they can also be based on keys like food-grade, origination and quality grades.

The CurvCode digital watermark contains a number of invisible or nearly invisible dots positioned along a so-called Bézier curve. CurvCode offers more than a thousand different codes. Image 1 shows the code for payload: “PET, neutral transparent, single layer, food.”Image 1 (Image credit: FiliGrade Sustainable Watermarks).

Depending on the packaging material, CurvCode can be applied through embossing as well as printing technologies.

CurvCode aims to meet the requirements of today’s industrial sorting and recycling stakeholders. It is a cost-effective and reliable solution which enables high-quality recycling as required by new EU waste-management regulations.

Marien De Lint, member executive board at FiliGrade Sustainable Watermarks.FiliGrade has already completed semi-industrial trials for multi-layer flexible packaging, paper-laminates and beverage cartons. Semi-industrial trials for rigid plastic packaging like HDPE and PET are planned for the second half of 2024. Industrial trials are expected in 2025.

How is the CurvCode watermarking technology helping the industry comply with the EU’s PPWR? 
De Lint: The EU’s brand-new PPWR framework requires supply chains and governments to bring packaging into a circular economy. Packaging and waste management stakeholders will need to invest in processes and systems fit for “high-quality recycling.”

The PPWR identifies granular sorting as a very important step in this transition and contains more than 50 references to sorting processes and requirements. CurvCode supports PPWR compliance. Firstly, CurvCode seeks to enable reliable, deterministic and cost-effective sorting based on type of usage as well as material composition. This way, single-use food-packaging can be separated from non-food packaging. This is a key first step to meet the European Food Safety Authority’s (EFSA) requirements and PPWR recycled content targets. 

Secondly, CurvCode aims to enable sorted fractions meeting specific technical criteria and purity levels not found in the market today. Also, EU member states need to establish formal systems for quality control and traceability of packaging waste streams. CurvCode digital watermarking intends to support collection and granular reporting of sorting and recycling performance.

What role does digitalization play in packaging waste management? 
Trombetti: Current waste management systems, within the EU and beyond, face significant structural challenges. These include the lack of sufficient volumes of high-quality recycled materials, the absence of harmonized waste collection systems and limited sorting capabilities.

A profound transformation of the plastics value chain is urgently needed, especially in light of the recent ambitious EU-wide mandatory targets for recyclability and recycled content in plastic packaging. The digitalization of the packaging waste industry can drive this much-needed change, offering the opportunity to not only improve the waste management system but also create value for the entire value chain.

The HolyGrail 2.0 Initiative is at the forefront of this revolution, focusing on innovation and digitalization to transform the European waste management system. This unique collaboration aims to enable a circular economy for packaging by digitalizing the sorting process in the waste management system.CurvCode technology supports PPWR compliance through cost-effective sorting and meeting technical criteria and purity levels.

The benefits of a digitalized waste collection system include post-disposal track and trace capabilities, enhanced transparency for improved reporting and fraud prevention.

Additionally, the sorting and recycling processes would greatly improve through digitalization, which would lead to enhanced sorting efficiency, more granular material streams, and, consequently, higher-quality recyclates.

How is the new project helping advance the circular beverage container economy in the Netherlands? 
Trombetti and De Lint: Dutch food-packaging stakeholders are serious about creating a circular economy for single use plastic packaging not covered by a Deposit Return System. This has proved a very tough nut to crack for PE and PP packaging. Key barriers include EFSA regulations, immature eco-modulation of EPR fees and lack of a food-safe sorting and recycling infrastructure.

Nonetheless, this project is expected to catalyze phased transition toward circular deployment of PE and PP beverage containers. The consortium sees HDPE milk containers as a strong starting point for several reasons. Almost all HDPE milk containers sold in the Netherlands are produced using the same and consistent quality of HDPE. Also, the volume of material is significant. Approximately 80 to 100 million of these containers are put on the market each year. Last but not least, HDPE is suitable for mechanical recycling.

The collaboration between FiliGrade, HolyGrail 2.0, Alpla, Farm Dairy and Pellenc ST is a project aiming to assess both the technical and economic feasibility of the CurvCode technology through a phased approach. The first step is to validate that HDPE milk containers can be sorted efficiently under semi-industrial conditions. As a next step, the consortium may look for new members to facilitate industrial trials. 

The project team is fully aware that it is not feasible to receive fast-track EFSA approval for using HDPE recycled feedstock for food-contact applications. It is likely that we will initially aim at deploying high-quality HDPE recycled material for packaging materials not requiring EFSA approval. This should provide an economic basis for this project in the near term. In parallel, we will continue efforts to ensure that HDPE milk containers can be used as feedstock for producing HDPE packaging that meets EFSA requirements.

By Natalie Schwertheim