Decontaminating industrial plastic waste to ease the planet’s burden
With Europe’s ambitious plastic recycling strategy and growing public awareness, a plastic pollution-free future seems more and more possible despite current obstacles. For example, the EU already recycles 32.5 % of its 29.1 million tonnes of plastic waste. But what about plastics that aren’t recyclable because of the hazardous substances in them? The EU-funded NONTOX project is now developing a novel recycling process that will increase the recycling rates of contaminated plastics from industrial waste. The focus is on plastics from waste electrical and electronic equipment (WEEE), end-of-life vehicles (ELVs), and construction and demolition waste (CDW) that contain dangerous additives and compounds such as flame retardants, stabilisers and fillers. The risks these additives and compounds pose currently bar industrial plastic waste from being included in the circular economy, leaving unfavourable options such as landfills or incineration as the only alternatives. NONTOX has developed Extruclean and CreaSolv®, two different technologies to remove hazardous substances from WEEE, ELV and CDW plastic waste streams. As stated on the project website, the aim is for these recycling technologies to remove “hazardous and undesirable substances such as flame retardants from the plastic matrix without breaking the polymer chains.”
A look at Extruclean
Led by NONTOX project partner AIMPLAS Plastics Technology Centre in Spain, Extruclean is an innovative process that extracts hazardous elements from plastics and enables efficient recycling of plastic waste. It takes advantage of carbon dioxide as a stripping agent that helps to eliminate volatile substances, odours and other contaminants. Specifically, the process consists of two extruders connected in a series. The first extruder features a gas port for injecting supercritical carbon dioxide into the melt polymer flow. In the second extruder, a vacuum degassing port allows for volatiles removal. According to AIMPLAS experience in previous projects, this technology has been successful in enhancing the quality of plastic recyclates from waste packaging streams, reducing the amount of contaminants considerably compared to conventional extrusion processes.
The CreaSolv® solution
Patented by German applied research organisation and NONTOX project partner Fraunhofer, the CreaSolv® technology has been adapted to WEEE, ELV and CDW plastic waste streams for the project. The process involves the separation of plastic composites and contaminated waste through a method called selective extraction. This mechanical recycling method makes it possible to recover very pure plastics based on their solubility. Target polymers are selectively dissolved in a solvent, and undissolved components are mechanically removed. Other dissolved substances are then removed at the molecular level, purifying the target material and producing high-quality plastics that can be used as a secondary raw material for the production cycle. So far, this technology has successfully demonstrated the extraction of brominated flame retardants from WEEE and CDW plastics. NONTOX (Removing hazardous substances to increase recycling rates of WEEE, ELV and CDW plastics) is coordinated by VTT Technical Research Centre of Finland. By 2022, the project team hope to have developed an economically competitive recycling process that can produce safe and high-quality secondary plastic materials from contaminated plastic waste. For more information, please see: NONTOX project website
NONTOX, plastic, waste, recycling, waste electrical and electronic equipment, WEEE, end-of-life vehicle, construction and demolition waste