By Plasteurope.com correspondent

In a demonstration, a high purity mechanical recycling process initially developed for yoghurt pots has been successfully applied to food trays made from extruded polystyrene (XPS). The test run was conducted by Styrenics Circular Solutions (SCS, Brussels; www.styrenics-circular-solutions.com) in partnership with German bottling machinery and equipment maker Krones (Neutraubling; www.krones.com) and Norwegian sorting specialist Tomra (Asker; www.tomra.com).

SCS said it has also developed a design for a recycling guideline for XPS food trays aimed at maximising recovery yield and quality. Most XPS food trays are already in line with the guideline, the recycling initiative added.

The partners used Tomra’s “deep sorting” equipment to produce a high purity XPS feedstock from mixed post-consumer PS waste. Krones was then responsible for shredding, hot washing, dewatering, and drying the feedstock.

“The test run demonstrates not only the technical capability of the process, but also the industrial feasibility to realise it competitively at typical recycling capacities, and with favourable levels of energy and water consumption,” SCS said.

Related: SCS project closes loop on XPS food trays

Krones said it has partnered with compatriot sorting equipment specialist and plant manufacturer Stadler Anlagenbau (Altshausen; www.stadler-engineering.com), Austrian recycling equipment supplier Maschinen- und Anlagenbau Schulz (MAS, Pucking; www.mas-austria.com/en), and Tomra to develop a Recycling Technology Center at its Flensburg, Germany, plant. At the centre, sorting and washing tests are organised for a wide range of packaging plastics including foamed material such as polystyrene EPS and XPS, the company said.