Could invisible markers hold the key to enabling a plastics circular economy?

An innovative new project that acts as an 'invisible barcode for plastics recycling' could streamline the way that food-based polymers are recycled after it received a two year funding guarantee from Innovate UK.

The Plastic Packaging Recycling using Intelligent Separation technologies for Materials (PRISM) project has secured £772,000 to support its bid to revolutionise the way that plastic waste is sorted, tagged and recycled – a move that could allow brands to establish a close-loop collection format for their packaging.

PRISM – which has been developed by a high level consortium consisting of project lead Nextek, WRAP and Evolve Polymers among others – will allow different coloured plastics and shrink-sleeves that often consist of different underlying plastics, to be separated at the recycling stage.

“This could be the equivalent of an invisible barcode for plastics recycling,” Nextek’s managing director Edward Kosior said. “It is a significant step forward in the sub-categorisation of plastics which are sorted automatically at high speed.

“It enables new initiatives from brand-owners eager to recover their packaging as part of the circular economy. Of course, it also provides a massive impetus for new businesses in the recycling sector.”

How it works…

The fluorescent label sorting system can be integrated with the near infra-red (NIR) systems used in material recovery facilities. By adding UV light scanners – which many facilities are capable of – a ‘unique code’ on the plastic is revealed to highlight the compounds of the material which is currently untraceable.

The technology has already shown initial promise. A research project led by WRAP found that identification and separation trials achieved 97% yield and 95% purity results.

The funding will be used to carry out the second phase developments including developing the invisible tags from powders and metal oxides to see how they react through the supply chain and whether they dissolve after processing.

WRAP packaging programme area manager Claire Shrewsbury said: “The new technology could help boost recycling plant yields, and UK plastics recycling as a whole, with more efficient ways of sorting materials such as polypropylene (PP) packaging, high density polyethylene (HDPE) milk bottles and sleeved polyethylene terephthalate (PET).”

PRISM estimates that adding the fluorescent markers would only add ‘minimal costs’ to the labels. The markers could also be applied to plastics common in the Waste Electrical and Electronic Equipment (WEEE) and automotive recycling streams.

Plastic streams

The new innovation could go a long way to help in diverting the amount of plastic that unnecessarily ends up in landfill – or even our oceans.

A recent study from the Ellen MacArthur Foundation revealed that applying circular economy principles to plastic packaging could save up to $120bn for the global economy. However the report also had a stark warning that current trajectory would lead to more plastic in the ocean than fish by 2050.

Last year the Government revealed new proposals to recycle at least 57% of the nation’s plastic packaging by 2017 – a target that WRAP has promoted through The Plastics Industry Recycling Action Plan (PIRAP).

Matt Mace

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