An estimated 370,000 tonnes in the UK and an estimated 4 million tonnes in the EU of plastic is sent to landfill because the plastic type cannot be identified, despite it being suitable for recycling.
This is because the vast majority of recycling sorting facilities use Near Infra-red (NIR) scanning technology, to identify and separate plastic from household waste into its different polymers. Any plastics which contain carbon black pigment (e.g. black, brown, dark green, dark blue colours) are not identifiable as the carbon black absorbs the infra-red waves and inhibits them from reflecting back to the sensor.
As such, we wanted to develop a solution to this major challenge in the handling of plastics against the background of the UK’s environmental aspirations. We had already proven the concept of developing NIR detectable pigment systems but now we are seeking to take this project to the next level.
Project Objectives
• The concept of NIR detectable pigment systems has been proven in previous work, which has produced black and dark coloured plastics that can be identifiable to NIR scanning technology and subsequently recycled.
• The NIRPlas project concept is to gain new scientific understanding of the inter-relationship between a plastic’s first life and its subsequent lives (e.g. after multiple loops of recycling, product manufacturing, recycling again) in terms of its visual changes and integrity of the plastic, when NIR detectable pigment systems are used.
• The NIRPlas project is also aiming to develop a novel, continuous NIR and visual inspection system so that the manufacture of NIR detectable polymer compounds can be certifiable, meaning there is added confidence that they can be recycled when being processed through a recycling sorting facility.
Project Outcomes
• An exceptional scientific understanding of NIR detectable plastics has been achieved. Across multiple plastic types, no significant differences in integrity have been identified for plastics being processed through a life cycle of up to 4 times, when compared with traditional pigmented plastics.
• The design and construction stages of the continuous NIR and visual inspection system have been completed with excellent results. Operational testing has been successfully conducted and ongoing modifications are planned. The prototype was fitted on to Luxus’ main production line in May 2021 for full-scale operational trails.
Our sincere thanks to our funding body,
Innovate UK and to our project partners,
Colourtone Masterbatch,
The Technology Research Centre and
Berry Global.