Recycling multi-polymer and multi-layer plastic packaging

German company, APK AG in Merseburg, is relying on the high-performance ZSK extruder technology and technical process expertise from Coperion to recycle previously unrecyclable packaging.

The Newcycling process allows multi-polymer and multi-layer plastic packaging, that previously could not be recycled, to be separated and processed into homogeneous regrind. In contrast to chemical recycling, the polymer in this process remains unchanged and does not require energy- and cost-intensive re-polymerisation.

This physical and solvent-based process enables clean and single-origin polyamide (PA) and polyethylene (PE) pellets with virgin-near material character to be extracted from complex PA/PE multi-layer films.  PA/PE multi-layer film is first mechanically pre-treated, including shredding and classification. Next, the PE layer is dissolved and liquefied in a solvent bath, leading to separation of the polymers and polymer layers. The undissolved PA is then separated from the dissolved PE using conventional solid-liquid separation technology and the polymers are further processed in separate material streams.

The PA is extruded and processed into a high-quality PA melt using very high dispersion performance and intensive devolatilisation. Finally, it is pelletised.

Following pre-evaporation, the PE is likewise introduced into the extruder with the solvent. There, devolatilisation of the liquid takes place and the solvent added back into the process in a closed loop. PE remains in the form of a homogeneous melt that is then pelletised.