PRODUCTION PROCESS
Comprehensive sorting is crucial for high-quality plastics recycling. Steinbeis PolyVert has various sorting techniques at its disposal. Depending on the area of application, manual sorting up to fully automated NIR-sorting ensures pure fractions. Near-infrared sorting (NIR) enables material-typical patterns to be detected after excitation with light. Due to the different spectra, materials can be easily separated from each other within certain wavelength ranges.
Post consumer and post industrial plastic waste enters the production as input material and is grinded in the mills. Our mills are suitable for all plastic fractions, from soft and small to hard and voluminous. The input material is thus transformed into homogeneous and optimally recyclable final sizes. The output is grinded material or flakes.
An essential part of the recycling process is the cleaning of the input material. In the course of the cleaning process, plastic fractions can be separated from each other due to different specific weights. The input material is put into a liquid bath (water). Heavy materials sink to the bottom due to higher density, lighter ones float on the surface and are thus separated. Impurities sink to the bottom of the water and are disposed as rejects.
The prepared material is converted into a melt and brought to the extruder. In the further production process two degassing processes (atmospheric / vacuum) take place. A screen changer removes impurities such as metal, wood, etc. The plastic is cooled down and fed to the pelletizer. Via oversize screen the pellets reach the centrifuge where complete drying takes place. The output is granulate in lenticular or cylindrical form.
The input material in the form of flakes is melted at the beginning of the process. Through a nozzle the material is formed into a thermoelastic film. This film is then cooled and wound onto a roll. By using new technical processes, it is possible to produce a film for the food industry from 100% recycled material.
Packaging material often takes on the smell of the food, detergents or cosmetics contained in it, often producing intense odours. With the ReFresher technology these disturbing odorous substances can be eliminated. In addition to highly volatile low-molecular substances, the Refresher also removes hardly volatile, high-molecular odour substances and an odour-optimised premium regranulate is produced.
Once the plastic waste is delivered to our production sites, the materials are sorted, grinded and cleaned. By melting (extrusion) of the material, regranulate is produced as output and then returned to the plastics industry in the sense of a circular economy.