At a Styrenics Circular Solutions event organized at K 2022, a panel of polystyrene value chain members were jubilant about the strides that had been taken in just the past years.
As Iain Sturges, the chief procurement officer at Coexpan, said: "Three years ago, we sat here looking at each other, saying we've got a big problem. Now, we've managed to turn around the situation, bringing polystyrene from a state near death to a survivor that has become the Rolls Royce of available materials."
This success has to do with the nature of PS, which is now much better understood than it ever used to be. In the first place, it enables the production of very optimized packaging, which is why such a high percentage of our yogurt packages are made from PS, said Florian Trohay, corporate social responsibility and sustainability manager at Yoplait. It is easy, convenient and functional.
And now it is also fully recyclable, in contrast to what was long thought, via three different processes. Dissolution, depolymerization and mechanical all deliver high-purity, virgin quality recycled PS that has been shown to be suitable for food contact applications.
"And the good news is that the readiness level of all of our technologies is 9 plus," said Jens Kathmann, the secretary-general of Styrenics Circular Solutions. Today, fully circular, food-grade low-carbon recycled PS has become reality, he added.
"We've gone from having a big problem to being this far away from saying 'mission complete' — we just need everybody's collaboration to pull this over the line in the next few months," Sturges agreed.
As a converter, Coexpan, which is a division of Madrid-based Grupo Lantero, has a choice of materials and could look at alternative materials but "in reality, you look at the path of least resistance and that path is to stay in polystyrene, because it's what you're already running," Sturges said.
"Using [recycled] PS allows us to keep all these advantages and contribute to realizing our decarbonization strategy, as well as being a way to reduce our dependency on oil-based materials," said Yoplait's Trohay. Yoplait is part of the French cooperative Sodiaal.
Jürgen Priesters, senior vice president of circular economy business for recycling equipment company Tomra Sorting GmbH, explained that part of the success of PS was due to its easy sortability. Styrenic compounds have a unique signal that enable easy and very precise sorting. It is highly suited to near-infra-red sorting technology and can be sorted very precisely into the different styrenic materials, such as into high-impact, general purpose or styrene acrylontrite copolymer (SAN).
"The technology we have today allows the different types of containers and packaging to be recognized by a trained computer as having been used for food or nonfood," Priesters said.
The non-food-contact materials can be used to create items like clothes hangers and plugs, while the food-contact materials, thanks to advanced cleaning capabilities, can be made into new food-contact items.
"It sounds simple, but you really need to feed the computer with thousands of pictures. Once you've accomplished this, it really works. The important thing is that it is recognized that it has food contact origin," he said.
The latter point is an important one, as only mechanically recycled plastics derived from food-contact applications have, up until now, been allowed to be used in new food-contact applications. SCS has already submitted two applications to the European Food Safety Authority, EFSA, for two super-cleaning technologies that produce food-grade rPS and is waiting for an opinion.
Meanwhile, the EU has changed the regimen: From July 10, 2023, only plastics containing recycled plastic materials manufactured with a suitable recycling technology or notified novel technology can be placed on the market. Recycled plastic food contact materials and articles must meet the same level of compositional, restriction, and specification requirements as newly manufactured plastics, in accordance with Regulation (EU) No. 10/2011.
Recycling technology is considered suitable if it is shown to be capable of recycling waste into recycled plastic materials and articles that comply with general requirements laid down in Regulation (EC) No 1935/20042 and is microbiologically safe. The European Food Safety Authority (EFSA) is required to provide opinions on whether novel recycling technologies are suitable to be used as a basis for recycling processes based on the kind of plastic input they are intended for, and the principles they apply for decontaminating that input.
A register of notified recycling technologies will be published. SCS is confident that the underlying criteria developed by EFSA to assess the safety of recycling processes remain valid, said Jens Kathmann, SCS secretary general.
David Eslava Sánchez, deputy managing director of Eslava Plásticos, emphasized that PS was already "well-designed for recycling."
However, there is always room for improvement, he added. Well-designed PS packaging increases sorting efficiency plus allows converters to use less material. "Even the LCA [life cycle analysis] will be better," he said.
Sánchez was speaking on behalf of RecyClass, the European nonprofit, cross-industry initiative facilitating the transition toward a circular plastic future. The group has, among other things, contributed to putting together the Design for Recycling Guidelines.
Coexpan's Sturges summed up the presentation, emphasizing that "any application produced with today's recycled polystyrene forms just as well as virgin polystyrene. Anything you can do with polystyrene can be done with recycled polystyrene. When choosing the rPS to use, you must first understand the objectives of the customer, to allow the path to the right solution to be found. We have lots of solutions to get to food-contact structures. But whatever solution is chosen, polystyrene has an answer for it."