Production of PE PCR pellets with a quality of over 0.9 related to processing and mechanical properties compared to virgin pellets

This deliverable is related to Task 3.5: Mechanical recycling tests and application development of the European Project CIRCULAR FoodPack. In this task, recyclates coming from the various Loops in the projects are compounded to granulates, ready for conversion into new products. A target was set to obtain recycled granulates with a quality value over 0.9 (on a scale 0-1). Furthermore, it was part of this task to assess how representative results from lab compounding can be for (semi) industrial compounding.We have therefore split the deliverable into two main parts as follows: RecyQmeter:This section assesses the quality of recycled products which are generated in this project using novel processes combinations such as using dissolution-based recycling or water-based deinking and delamination. The focus in this calculation has been on Loop3 (cycle1) materials. It uses a combination of two published quality models (Demets, 2021 and Golkaram, 2022). The results show that the recyclates are well-suited for blown film extrusion applications. Among those, the shrink and heavy-duty films are the best markets with quality value of around 0.94-0.95. However, the quality value for shrink film applications may vary because not all tests were conducted for this specific application. Instead, a general set of tests was conducted to assess the quality across various applications, leading to a higher deviation in the evaluated results. Extruder trial:In addition to the quality assessment of recycled products, an extruder trial was conducted on Loop2 materials. Since the size of an extruder significantly affects the shear rates experienced in the melt, it can influence homogenization and potential thermal degradation of the extruded plastic. An 18 mm co-rotating twin-screw extruder (TSE) at lab scale was compared with a 25mm co-rotating TSE at semi-industrial scale as part of an intermediate process preceding the actual industrial recycling step. Overall, while the 18 mm Coperion extruder exhibited decreased oxidative stability compared to the 25 mm Krauss-Maffei, no other substantial differences were observed in the tests conducted. This suggests that, aside from oxidative stability, both extruders perform comparably in the evaluated tests. Note: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003806.