PETpla.net Insider 07+08 / 2020

BOTTLE MAKING 42 PETplanet Insider Vol. 21 No. 07+08/20 www.petpla.net rPET in stretch blow moulded bottles The first PETinar attracts more than 200 participants by Alexander Büchler The first PETinar organised by PETplanet Insider took place on the 28 th of May 2020. PETplanet invited three specialists to discuss the topic of manufacturing and processing rPET right through to a blown PET bottle. Mr Stefan Bock, CEO of RedupPET, expert in the field of preform production, moderated the discussion. The first presentation was delivered by Mr Christoph Wöss, Business Development Manager, Bottle Application at Erema Group. Christoph introduced the new bottle-to-bottle recycling technology Vacunite from Erema. He was followed by Mr Arne Wiese, Product Manager Bottles & Shapes at KHS. Arne described and analysed the processing from an rPET preform to a blown rPET bottle. Christoph Wöss, Erema began his presentation with a brief overview of PET recycling. Most of the 268 PET food-grade machines sold world- wide have gone to the bottle-to-bottle sector (95 units), closely followed by the bottle-to-sheet sector (77 units). The remainder went to other areas including PET palletising fibre. The systems have a total capacity of 2.3 million tonnes per annum. Christoph spoke of a most recent development, the Vacunite recycling system, which has already got off to a good start with 11 machines planned worldwide. Compared to Erema’s ear- lier bottle-to-bottle systems, the idea of working with vacuum and nitrogen is still in its early stages. Vacunite is a combination of the proven Vacu- rema technology and an assisted SSP (Solid State Polycondensation) at reduced pressure under nitrogen, patented and designed by Polymetrix. In the Vacunite system, the extruder is short with backward degassing at the melting zone. For a higher degree of crystallisation, a new, compact inline crystallisation system was added. It shows no sticking behaviour because the shift of low melting peak is above drying temperature. The technology reduces yellowing due to vacuum and N2 and generates a reliable decon- tamination, which is FDA & Efsa approved. The low IV decrease in the vacuum reactor enables a high increase of the IV in the SSP. The IV increase is determined by the process temperature (190-210 °C) and pres- sure (100-200mbara). Christoph con- cluded that the Vacunite technology is a well-controlled thermal process, has very high energy efficiency and is officially food contact approved. It has an output from flake to pellet up to 0.35 kWh/kg. The participants were chiefly inter- ested in some technical details about the system, together with the stability and quasi-quality of rPET. Arne Wiese, KHS explained the material difference between PET and rPET. While colour variation, IV and IV variation are all pretty similar, rPET is slightly darker and much more expensive (1EUR to 1.25EUR/kg). The factor that most strongly repre- sents a variance to virgin PET is the colour and the cost of the recycled material. The impact on the blowing process is based on experiences with an InnoPET Blow Moulder Series V PETinar Arne Wiese, Product Manager Bottles & Shapes KHS Christoph Wöss, Business Development Manager, Bottle Application Erema Stefan Bock, CEO RedupPET