NOVEMBER 2011

New processes could make junk plastics recyclable

The findings from a series of trials funded by Waste & Resources Action Programme (WRAP) show it could soon be possible to recycle almost all plastic packaging waste from the home.

Despite more than 330,000 tons of plastic packaging being collected for recycling each year, more than a million tons still end up going to landfill because of the difficulty of collecting and recycling films, the difficulty in detecting and sorting black plastics and the lack of high value markets for non-bottle plastics.

A series of trials, funded by WRAP, have for the first time identified methods of recycling black plastics, complex laminated plastics, plastic films and polypropylene (PP) that would typically be destined for landfill.

For example, by using non-carbon pigments in the manufacture of black plastics, it is possible to create a material that is almost identical in color, but can be identified by the optical sorting equipment used by many MRFs. This could lead to the widespread recycling of the most common plastic used in packaging. Feedback from retailers has been encouraging, and the plastic trays could be recycled into high value single-polymer materials.

Complex laminated packaging, the material used in toothpaste and cosmetics tubes, contains a layer of aluminium sandwiched between plastic, and a second trial has identified a way to extract this high value aluminium. WRAP estimates that there is around 155,000 tons of this laminated packaging in the UK waste stream with an aluminium content of around 14,800 tons.

A third study has seen the development of a technique that could recycle post-consumer PP back in to material suitable for food-grade applications. More work is still needed, but WRAP believes this could help to grow high value markets for recycled PP, following a similar path to that developed by rHDPE and rPET. It could also deliver higher environmental benefits as retailers and brands start to use it in their packaging.

And work done by The Co-operative Group and Sainsbury’s, with WRAP, has identified a variety of uses for plastic films recycled in-store by customers and staff. These applications include bags for life, in-store signage and external cladding.

A system has also been developed that cleans and recycles contaminated film, producing a pellet with a sales value of $550 to $750 per ton. With the cost of sending this material to landfill currently at $130 per ton, the advantages are clear.

Marcus Gover, director of Closed Loop Economy at WRAP, said, “When we first looked at recycling non-bottle plastic packaging back in 2007, we carried out detailed studies to make sure it would be technically and economical viable.

“We also carried out a thorough life-cycle assessment to make sure it was the best environmental option. We’re now seeing this recycling becoming a reality, creating jobs and re-invigorating the manufacturing industry in the UK – reducing our reliance on exports.

“There have been, and there are still, barriers to overcome, and WRAP will continue to work closely with the industry to develop these new methods and technologies so that in the future, local authorities can offer their residents a way of recycling even more of their plastic packaging.”