Multilayer packaging consists of individual nanometer-thin layers of different plastics that keep the packaged food fresh, aromatic, and protected for a long time with little use of resources. However, the films, which are bonded with plastic adhesives such as polyurethane, cause problems when it comes to material recycling because they cannot be separated from each other using classic processes such as shredding, sieving and centrifuging. The approach of the students of the Karlsruhe Institute of Technology (KIT) is a solvent process to dissolve out the adhesive between the films in order to separate the plastics by type. The five young engineers from the same semester call the shipping box produced from the plastics thus obtained Recycled Polymer Packaging Karlsruhe - RepoPaK for short. This second part of their approach reportedly meets several requirements: Thanks to its honeycomb structure, the shipping crate is lightweight and stable, waterproof and can be transported by drones. Foldable, it can also be stored to save space. In the end, the crates, which are made of pure plastic, should also be easy to recycle.
With their concept, the students won first prize in the nationwide chemPLANT competition for creative young process engineers (kjVI) in the Process and Chemical Engineering Society of the Association of German Engineers (VDI) 2021. The competition task was to develop an innovative, sustainable and economical concept for recycling materials from the household waste mix of a typical large city into a higher-value product.
Sources:
- recyclingportal.eu (12/14/2021)
- Photo: @ Team KIT