WRAP believes it has created a system that will boost the recycled content of food packaging.
The body concluded the technical testing of a method of sorting food grade plastics that could increase the recycling of pots, tubs and trays in the UK.
It presented the preliminary results of its trial of the technology to representatives of the retail and recycling industry in June, and published a report on it on 22 July.
WRAP will then aim to start a commercial trial of the sorting process, as it works to encourage recyclers and packaging producers to create a nationwide system.
“It’s hoped that these results [of the technical trial] should provide confidence to the packaging and recycling industry to take on the development using the methodology presented in the report to develop and commercialise a food grade recycling process for post-consumer PP packaging,” Claire Shrewsbury, programme area manager for packaging at WRAP, told MRW.
“Retailers want to use more recycled content in their packaging, the problem is that it needs to be food grade standard,” said Shrewsbury.
WRAP’s research focused on polypropylene (PP), a polymer widely used in food packaging. Some 40% of pots, tubs and trays in the UK are made of PP.
Only PP that has been in contact with food can be recycled into new food grade PP under UK and US food packaging regulations. So the first issue WRAP had to solve was finding an economically viable process to separate PP that had been in contact with food from that which had not.
As manual sorting would be too expensive, WRAP developed an automatic system to separate materials using a process called diffraction gratings.
The process consists in marking PP material with lines that can be scanned by a laser to reflect a specific pattern. The pattern is then captured by a camera connected to a computer system able to separate the marked PP packaging.
“WRAP will continue to work on identifying packaging that has been in contact with food as this has wider applications than just PP recycling and could give confidence to other food grade processors,” said Shrewsbury.