When up to 10% compostable plastics are mixed with conventional plastics in post-consumer recycling streams, there is no or negligible impact on the mechanical performance of the recyclates. This is the key finding of a meta-study, “The behaviour of bioplastic films in mechanical recycling streams,” published by European Bioplastics.
Notes the study, bioplastics are biobased, compostable, or both. Biobased plastic films are chemically identical to their conventional counterparts and are easy to manage in recycling streams. Compostable plastics are designed for organic recycling and should be collected accordingly. They are marked for this purpose with logos such as the Seedling from European certification body Vinçotte.
In the event that compostable plastics end up in recycling streams, the prevalent sorting technologies are able to sort them with little residual waste, the meta-study indicates. “Studies and field trials have demonstrated that in the uneventful case a small fraction of compostable plastics ends up in the PE recycle stream, this does in no way negatively impact the quality of the recycling stream,” says François de Bie, Chairman of European Bioplastics. “Remaining amounts are easier to handle than other residual wastes in the polyethylene stream, such as polystyrene or polypropylene.”
This was proven up to a share of 10% compostable plastics in the recycling stream by independent studies of the Institute for Bioplastics and Biocomposites (University of Applied Arts and Sciences Hannover), the Italian National Packaging Consortium (CONAI), and the company BIOTEC.