From 21st to 24th January 2020, the PolyCE team participated at the 19th International Electronics Recycling Congress IERC 2020 in Salzburg.
On the first day of the IERC congress, the PolyCE team and 25 participants from research and industry came together for an interactive workshop to discuss the challenges and opportunities to recycling of plastics from Waste Electric and Electronic Equipment (WEEE). The main aim was to explain the complexity of recycling of WEEE plastics and show the potential of WEEE recycling optimization. Four working groups brainstormed around the presented approaches in the afternoon session.
Optimized WEEE clustering
Jef Peeters (KU Leuven) and Alessia Accili (ECODOM) showed how innovative WEEE clustering can limit the mixing of difficult to separate and incompatible materials. In this manner the innovative clustering strategies can significantly improve the quality of output materials while enhancing the WEEE plastics recycling rate and limiting the degree of contamination in output streams.
However, every innovation needs to be financially viable prior to industrial implementation and the participants provided valuable feedback on the effectiveness and feasibility of the proposed solutions. The consulted stakeholders pointed out that the economic viability of the clustering strategy can be affected by several factors, such as the required manual labor costs for the sorting, space constrains, procession time variations and low quality of the input material arriving at the WEEE pre-treatment plants.
Optimized WEEE pre-processing
After collection, WEEE undergoes several decontamination and size reduction steps. Different size reduction technologies produce different flake sizes. Franziska Maisel (Technical University Berlin) presented the potential behind a standardized flake size not only for the subsequent sorting process, but also considering the positive effect on transportation and storage cost. The main message to WEEE actors on how to improve pre-processing of WEEE are as follow:
- Sorting of pure plastic fractions before shredding, wherever economically feasible
- Improve communication between pre-processors and recyclers
- Implementation of a standard flake size (10–20 mm) of the plastic fraction
- Keep the production of fines low by reducing the number of shredding steps and the choice of an adequate shredding technology
- Sort out brominated fractions before transport to the plastics recycler
- Remove contaminants, such as glass and wood, prior to the shredding
- If feasible, separation of the fine fraction by suitable sorting technologies
Quality testing of PCR plastics
A high and well controlled quality of recycled plastics is a prerequisite for their reapplication in new electric and electronic products. In order to deliver consistent high quality post-consumer recycled (PCR) plastics, the generation and communication of valuable quantified information is needed between the different partners in the value chain. Jef Peeters presented a quality testing approach, co-developed with UL, which goes beyond a minimum definition of quality and provides a targeted quality management and information transfer scheme. This scheme allows a complex value chain to generate and share relevant quality criteria along the value chain in an efficient manner.
A novel testing technique at the phase of plastic flakes was presented focusing on a testing scheme that allows to generate the information relevant after product shredding and/or plastic sorting, which often covers the communication between recyclers and compounders. A testing scheme based on XRF, FTIR technology, computer vision, sieving and composition analysis allows to test the size distribution, the colour distribution, fines content, as well as the Bromine content and plastic type composition. In addition, a scheme was presented to gather important metadata that is generated in the early phases, during collection and pre-processing, which can give more transparency to the tested plastic flakes history. All information is summarized in a datasheet for plastic flakes integrated in the phase-gate approach for quality criteria at this phase in the value chain.
Design for and from Recycling for circular product development
Gergana Dimitrova (Fraunhofer IZM Berlin) and Günther Höggerl (MGG Polymers) presented best practice examples for improving the circularity of plastics, taking into account Design for Recycling, as well as Design from Recycling, strategies. The Design for Recycling strategy shows best practices during the product development process, following the design phases of material selection, part and product design. These guidelines allow optimising the design of a product in such a way that all valuable materials are effectively recovered with current recycling technologies at the end-of-life. The more innovative Design from Recycling strategy looks to what extent new products can be manufactured using recycled plastics. The guidelines are still in a draft phase and are being completed in the course of the project by Fraunhofer IZM, Pezy Group, MGG Polymers and Ghent University.