Extrusion Asia Edition 1-2024

格诺斯测量技术产品 Gneuss measurement technologies products OMNI recycling machines for closed loop recycling The Gneuss MRS Extrusion Technology is well known as an al- ternative for the recycling of contaminated materials such as Polyester (PET), Polystyrene (PS), Polypropylene (PP) or Polyethy- lene (PE). In combination with Gneuss' highly efficient Rotary Filtration Systems, optimised vacuum technology, an Online Viscometer VIS and Gneuss measurement technology, customi- sable recycling lines can be designed for a specific material. As an option, material can be fed to the extruder via a 3C Rotary Feeder. Multiple Letters of Non-Objection (LNOs) from the FDA, EFSA compliance and local approvals in Latin America confirm the decontamination efficiency of the technology. Typical applications for OMNI recycling machines include the processing of PET scrap, such as bottles, sheet regrind or fibre waste, into high quality end products such as thermoformed sheet (suitable for food contact), staple fibre, POY, FDY, BCF or strapping. In addition, a wide range of raw materials such as PS, PP, PE, PLA can be recycled. The OMNI series is also used in the decontamination of post-consumer waste for the produc- tion of direct food contact products such as HDPE bottle caps, coffee caps and for odour reduction and degassing of PA, SAN or other polymers. In addition to its compact design, which takes up very little space and can therefore usually be easily integrated into exist- ing premises, the OMNI scores highly in terms of flexibility. The fully automatic control of vacuum, extruder, dosing, degassing time and filter change ensures a consistently high quality of the end product while allowing the operator to use lower cost raw materials. In today's tight and fluctuating materials market, it is becoming increasingly important to be able to produce regard- less of the properties of the input materials, especially in the fu- ture when the quality of the input materials will vary and be un- certain. The compact design also results in very low energy consumption. Any energy used in the extrusion process is designed to be used in the next process step. This not only has a no- ticeable effect on electricity and gas consumption, but also significantly reduces the CO 2 footprint of the re- cycling process. Multiple screw extruder MRS The MRS extruder is based on con- ventional single screw technology but is equipped with a multiple screw section for devolatilization. It enables very efficient and gentle de- contamination of the polymer melt, whilst achieving the requirements for direct food contact stan- dards. In addition, the MRS extruder permits the processing of R-PET directly into high quality end products such as packaging sheet, strapping tape or filaments without pre-drying by using a simple and rugged vacuum system. All this is achieved by means of its unique and patented processing section. The Mul- ti Rotation Section is a drum containing multiple satellite single screws, driven by a ring gear and pinion transmission. The satellite screws rotate in the opposite direction to the main screw. This disproportionately increases the surface exchange of the polymer melt. A large opening for venting, exposing the full length of the satellite screws, is completely under vacuum. This provides excellent and unrestricted access to the polymer melt, the surface of which is constantly replaced at an extreme- ly high rate by the action of the satellite screws in the multiple screw section. The surface area – and the surface area ex- change rate – available for devolatilization are far greater than in other extrusion systems. As the thermal and mechanical stress on the polymer melt is minimized, reclaim processed on the MRS extruder has excellent optical and mechanical proper- ties. In a single, simple extrusion step, harmful contaminants can be removed so thoroughly that the resulting recycled pellets are safe for use in food contact applications. Vacuum system Gneuss has developed its own vacuum systems for the extrac- tion of volatile impurities, some of which have patented sepa- ration systems. Due to the large melt surface in the MRS extru- der, the suction capacity is considerably higher than in conven- tional systems, so that large quantities of volatile impurities can be extracted from the polymer and separated from the vacuum flow by means of automated separator systems. In addition to 46 2024中国国际橡塑展 – Chinaplas 2024 Extrusion Asia Edition 1/2024