If post-consumer recycling materials are to be processed directly into PET sheet, with a process authorised by FDA or by EFSA, an indispensable solution is required. With its IR-Clean System, Kreyenborg now offers an alternative for post-consumer materials and direct decontamination processing of PET – without any kind of vacuum technology.
The system is an advanced development in the process technology of the well-proven IRD Infrared Rotary Drum used in hundreds of industrial applications. The standard process of crystallisation and drying of PET post-consumer bottle flakes in the IRD has been refined by various changes in the process parameters and technical modifications – this has resulted in good decontamination results which have been proven in tests in collaboration with the Fraunhofer Institute for Process Engineering and Packaging IVV. The Food + Drug Administration FDA has issued a Letter of Non-Objection on the basis of these values. These results can also be used for the limits, fixed on behalf of the European Food Safety Authority EFSA – depending on the use of the end product up to 100% of post-consumer material.
The key to these good results lies in the general functional principle of the Infrared Rotary Drum – the low mass in the process and the continuous movement of the material ensures a continuous surface exchange of the recycling material to be treated. Combined with the direct heat input from the infrared light, which generates high temperatures within a few minutes, the IR-Clean concept needs no expensive and high-maintenance vacuum systems. IR-Clean combined with a downstream Finisher, that takes the form of a desiccant air drier, giving drying values of <50ppm. The IR-Clean system achieves the FDA / EFSA values already upstream of the extruder, facilitating easy retrofitting and, thus, an FDA / EFSA approval of existing single-screw, twin-screw or multi-screw extrusion systems. The package, developed by Kreyenborg is stated to not only comprises the conveying technology but also to complete process monitoring and documentation of the process parameters.