Extrusion Asia Edition 1-2020

Filtration of highly-contaminated recycled materials with the fully-automatic, pressure-constant and process- constant Gneuss Rotary Filtration Systems The Gneuss Rotary Filtration Systems with patented filter disc technology are ideally suited for the processing of recycled ma- terial, as they operate continuously, with constant pressure and fully automatically. Due to the annular screen arrangement a screen change takes place without disturbances or interrup- tions of the production process: • Depending on the filter fineness, the screens can be reused up to 400 times, which can mean a fully automatic filtration process without the need for several weeks of personnel. • Constant production process even with finer filtration to achieve high end product quality. • Automatic screen cleaning of the RSFgenius Filtration Sys- tem by means of an integrated backflush piston system, where a small amount of filtered melt is regularly shot through the dirty screen. By using the right filtration system, such as the pressure-con- stant and process-constant RSFgenius Filtration System with back-flushing technology, the quality and productivity restric- tions to be expected from a high use of recycled material can be considerably minimized. MRS Extruder with high decontamination performance for the direct use of PCR in the production of plastic packaging When post consumer and industrial waste is processed, the re- cycled plastics from previous use contain chemical additives such as dyes, stabilizers, acetaldehyde scavengers, carrier oils, solvents and many more. For the use of recycled material in contact with food or skin, the purity requirements set by food authorities such as FDA, EFSA or other local authorities apply. All organic and inorganic potential toxins must be removed, which is achieved with a high decontamination performance during the degassing phase. For more than a decade, the Gneuss MRS Extruder has been used for the recycling of highly contaminated recycled materials such as post-consumer waste, polyester industrial waste from fibre and film production as well as polystyrene, nylon and oth- er hydrophilic polymers. The MRS Extruder is based on a conventional single-screw ex- truder combined with a multiple screw section in the degassing zone: • the melt surface area available for degassing is increased many times over thanks to the multi-screw element with eight individual satellite screws rotating against the extruder barrel • vacuum degassing with a simple vacuum of 25-30 mbar • extremely effective removal of volatile impurities, oils and odours • processing of polymers with a moisture content of up to 1% • effective decontamination of 100% post-consumer recycled products and 100% bottle flakes for use in food contact with, among others, the LNO of the FDA, the EFSA approval or sever- al local approvals The MRS recycling technology is modular and can be easily in- tegrated into existing production lines. By replacing individual components or integrating the complete Gneuss processing unit, based on a Rotary Filtration System, an MRS Extruder with vacuum system and control technology, existing production processes can be made fit for the recycling cycle. System solutions for recycling of packaging waste Gneuss offers turn-key lines for the production of thermoform- ing sheet from recycled material as well as for the pelletizing of all types of plastic waste. One area in which MRS extrusion technology is particularly suc- cessful is PET sheet extrusion. More than 30 tailor-made Gneuss sheet lines were installed worldwide in recent years. The enor- mous flexibility of the lines, which process both virgin and recy- cled material and which are also used for packaging articles with food contact, has convinced many processors: • economically process without pre-drying and crystallization • flexible processing of a wide variety of materials such as virgin material, post-consumer bottle flakes and mixtures such as PET and PE or PET and PETG • many years of experience in processing into a wide variety of packaging products such as transparent film packaging for food and non-food articles, blister packaging, thermoformed trays and trays for food • flexible conversion to foam film production by means of physical foaming with a density reduction of over 50%. 图3: 100%回收料制作的PET最终制品 Picture 3: PET end products made of 100 % recycled material Gneuss Kunststofftechnik GmbH Moenichhusen 42, 32549 Bad Oeynhausen , Germany www.gneuss.com 33 Extrusion Asia Edition 1/2020