Extrusion International 2-2023

27 Extrusion International 2/2023 Chemical Recycling of Hard-to-Recycle Plastic Waste into New Plastic Pipes  Neste, Borealis, Uponor and Wastewise have successfully pro - duced pipes made of cross-linked polyethylene (PEX) which was based on feedstock gained from chemically recycled post-industrial waste plastic from PEX pipe produc - tion, using an ISCC PLUS certified mass-balancing approach. The part- ner companies believe this project is among the first implementations of chemical recycling of PEX. PEX pipes are an important con - tributor to energy efficient heat- ing and safe plumbing due to their robustness, temperature resistance and longevity, yet the intercon- nected polymer chains make them nearly impossible to recycle with conventional recycling technolo- gies. The project shows that chemi- cal recycling can close the circular- ity loop for hard-to-recycle waste plastic, turning it into high-quality polymers feedstock and enabling the consecutive manufacturing of products with quality and proper - ties identical to those in their previ - ous life. The cooperation sees Wastewise use their novel pyrolysis-based chemical recycling technology to liquefy industrial waste from Uponor’s PEX pipe production, breaking the polymers down back into their building blocks, which cre- ates an oil-like recycled intermedi- ate. This liquid is then co-processed in Neste’s oil refinery in Porvoo, Finland and upgraded into recycled Neste RETM, a high-quality drop- in feedstock for the production of new polymers. Borealis is feeding this raw material into their steam cracker and consequently polym - erizing it into polyethylene as part of the company’s BorcycleTM C, chemical recycling portfolio. Finally, Uponor is using the polyethylene to create new PEX pipe systems, which can then be used in the construction sector for heating, plumbing and cooling purposes once more – eli- gible even for sensitive applications with high requirements, for ex- ample those used for drinking wa- ter systems. The whole value chain is traceable via ISCC PLUS certified mass-balancing. Due to the involved parties’ com - mitment to pushing circular solu- tions for polymers and the solution’s drop-in character, the partners were able to establish the value chain in a rather short period of time. Little more than six months passed be - tween the start of the project and the production of the first pipes made with chemically recycled PEX waste. The partnership holds potential for further cooperation beyond pro - duction waste: The PEX pipes made by Uponor have already been op- timized from a resource efficiency point of view by reducing their wall thickness and increasing lifetime. At the end of their long life, me- chanical recycling is so far the first recycling option, but it also means downcycling the materials, e.g. into other construction materials or items. With chemical recycling, though, the PEX waste pipes can be turned into fully functional PEX pipes again. Moving forward, the partners will evaluate further op - portunities for cooperation. Aside from broadening the waste materi- al pool, this may also include higher recycled volumes. Borealis AG www.borealisgroup.com Neste neste.de Uponor GmbH www.uponorgroup.com WasteWise Group Oy www.wastewise.fi PEX pipe production at Uponor (Source: Uponor) More efficient than Energy efficiency class 10 Bekum uses energy-saving drives that feed their brak- ing energy back into a DC link, allowing it to be used in the extruder drive, a permanent consumer. This reduc- es the effective energy consumption for carriage and clamping plate movement to about 1 kWh per operat- ing hour for small blow moulding machines. In combination with the new energy-optimized HiPEx extruders, this makes a specific energy consumption of less than 0.26 kWh/kg (EBLOW 408D show demonstra- tion value at K 2022) possible – and this exceeds to the most efficient Class 10 according to EUROMAP 46.1. BekumMaschinenfabriken GmbH www.bekum.com