Carving out a new plastics economy
Image credit: Prevented Ocean Plastics
As leaders finally grasp the gravity of the plastic pollution problem, new efforts are being made to build a more sustainable future for this versatile but pervasive commodity, including cutting-edge alternatives and engineering innovations in waste management and processing.
The world’s plastic waste problem has reached a crescendo. The estimates are stark: over the next 20 years production is expected to double, creating the risk that, if nothing is done, the roughly 14 million tonnes leaking into the ocean each year will grow twofold.
These stark statistics were surely at the forefront of the minds of the 173 country reps as they came together to pledge to develop a historic and legally binding global treaty addressing the full lifecycle of plastics. The resolution, agreed at the UN environment assembly in Nairobi, Kenya, in February, will see a plan hashed out over two years to end plastic pollution, including provisions for financial and technical support.
“It’s impossible to overstate the importance of this treaty,” says Yoni Shiran, partner at SYSTEMIQ, a ‘think-and-do’ tank, and co-author of a new report, ‘ReShaping Plastics’, on how to achieve a climate-neutral plastic system. “If it’s even half decent, it can be a game changer for the global plastic system [and] bring alignment on definitions and resources at a very different level.”
So far, the plastics debate has felt “dysfunctional” with different camps making noise but no real progress, he adds, but now it’s evident how “critical” the topic is currently perceived “when even a global pandemic and a war in Europe has failed to derail global collaboration on the issue”.
According to ‘ReShaping Plastics’ and another landmark study from the US, ‘Reckoning with the US Role in Global Ocean Plastic Waste’ – commissioned by bipartisan legislators and published in December, and which its chair, Monterey Bay Aquarium chief conservation and science officer Margaret Spring, says pushed the US to participate in the global treaty – the solutions are known and the technologies are largely available. If both were acted on and invested in in a co-ordinated manner, a new plastics economy could be achieved in-line with global climate change targets.
Recycling is a high priority. The flow of plastics could be reduced by 80 per cent with existing waste management and recycling technology, according to Shiran’s report. Yet most recycling systems are insufficient or overly complex; so much so that approximately seven billion of the estimated 9.2 billion tonnes of plastics produced between 1950 and 2017 are now waste.
Mechanical recycling, whereby plastic is physically broken down but remains chemically unaltered, is most common but it has its limitations. It can’t handle multi-layer plastics and is greatly impacted by design.
Chemical recycling is the alternative. This process uses chemistry to essentially reverse manufactured products back to their original components. It can tackle flexible and multi-layer plastics and even composites like glass fibre, as well as food packaging that doesn’t meet the food safety and hygiene requirements for mechanical recycling.
The technology is rarely used in Europe and the US, but a form of chemical recycling known as pyrolysis has been active in Asia for 20 years, says Thierry Sanders, director of waste footprint solutions company Circular Action BV. It’s used largely to convert rubber tyres to oil, and plastic to fuel via a heating process (400°C and higher) that breaks down the solid waste to separate the gas, the oil – crude, later refined into diesel at a 55 per cent to 75 per cent conversion rate – and solid waste, such as carbon wax, which can be used to make asphalt.
Sanders says the technology is “wonderful” for lower-value plastics but has a bad reputation because it’s difficult to build well. “Many DIY ‘engineers’ built their own pyrolysis machines with leaks, allowing oxygen to enter during the heating process, which causes dioxins to be emitted that are very dangerous and carcinogenic,” he explains. “But most modern and industrially built machines meet EU standards.”
Another form of chemical recycling includes depolymerisation, which uses a similar process to pyrolysis to separate resins. Wind turbine manufacturer LM Wind Power, as part of the ZEBRA (Zero wastE Blade ReseArch) consortium, has developed a thermoplastic wind turbine blade that can be depolymerised at the end of its life using thermal and chemical recycling processes that heat to separate the fibre from the resin. It’s hoped the liquid produced can be reused in new thermoplastic resins to make new wind turbine blades and to stop blades going to landfill.
These technologies, though still small-scale, are attracting investment. US-based Eastman Chemicals announced in January it is set to build the world’s largest molecular recycling plant in France to process 160,000 tonnes of polyester waste products annually – enough to fill the Stade de France national football stadium 2.5 times, according to the company – to create virgin-quality materials.
Chemical recycling can scale to three million tonnes by 2030, but Shiran cautions there are “big questions around its climate footprint” and believes mechanical recycling should be the priority. “Getting the balance right is important,” he says.
A WWF position paper is more unequivocal; it states that only material-to-material applications of chemical recycling – i.e., not pyrolysis – should be considered recycling, and that plastic produced via chemical recycling should be verified with a ‘chain of custody’ documentation trail, as the public cannot distinguish it from virgin fossil plastic.
Plastic consumption in developed countries is 2.5 times higher per capita than in developing ones, according to thinktank Planet Tracker. Yet it’s estimated that most plastic enters the oceans in the global south via litter in coastal regions, where there is very little recycling infrastructure. Instead, plastic is often collected by an informal army of waste collectors.
Bantam Materials has developed a process by which it takes this rubbish, mostly PET plastic bottles, and mechanically recycles it, including putting it through an EU-approved decontamination process, to sell to the West. The product, ‘Prevented Ocean Plastic’, is defined as plastic waste collected within 30 miles of the coast, in an area without a formal waste-management system, and that is at high risk of ending up in the water if not collected.
The entire process is verified by OceanCycle, which has been pivotal to winning trust in a product that, because of its origin, is often wrongly considered of lower quality, with major brands such as Lidl, Sainsbury’s and Waitrose all currently using it.
While there is a certification cost attached, the plastic is priced at a comparable level to that of other recycled plastic, according to Raffi Schieir, director of Bantam Materials. “Our partnership with Lidl shows this isn’t a cost issue,” he says. “New plastics are only a tenth of a penny less expensive than recycled ocean-bound plastic.”
In March, Klöckner Pentaplast signed an agreement with the company to use a minimum of 30 per cent recycled plastic in its range of rigid films and trays for protein, produce and food-to-go. Bantam Materials estimate this will prevent 200 million plastic bottles from entering the ocean.
In 2020, the company processed around 13,000-14,000 tonnes of fully certifiable recycled plastic, with business being driven by a UK and EU plastic packaging tax that will apply from April 2022 to producers of packaging that does not contain at least 30 per cent recycled plastic, whether imported or manufactured in the UK or the EU. Similar legislation in the US could drive further demand, says Schieir.
Downstream solutions are just one side of the coin. “We also need to reduce the amount of plastic we’re producing, to innovate and create substitutes that have a clear end-of-life strategy,” says Monterey Bay Aquarium’s Spring.
Innovations are emerging. They include California-based Apeel’s edible plant-derived invisible packaging for fresh fruit and veg. The colourless, odourless and tasteless coatings are made of the lipids and glycerolipids that exist in the peels, seeds and pulp of all fruit and vegetables and are designated as GRAS (Generally Regarded as Safe) by the FDA. The powder-based product can be mixed with water and sprayed or brushed onto products. The technology helps produce stay fresh two to three times longer by keeping moisture in and oxygen out. The company, which was founded in 2012 with a grant from the Bill & Melinda Gates Foundation, has been successful in attracting investors but currently only has one product in US supermarkets – Apeel avocados.
Similarly, sustainable packaging start-up Notpla produces packaging made of seaweed and plants that naturally disappears. It’s ‘Ooho’ product, which was funded by Innovate UK and the Ellen Macarthur Foundation, is an edible and fully biodegradable sauce sachet targeted at the takeaway sector – restaurateurs can buy Heinz ketchup sachets for 25p apiece. The team worked with chemists and chemical engineers from Imperial College in London to test Ooho at running events, festivals and takeaway shops and eventually developed a bespoke manufacturing machine. It plans to test, scale-up and lease or sell the technology to food manufacturers, co-packers, and event organisers.
Reuse solutions are also innovating. Chile-based Algramo uses what it calls a ‘Packaging as a Wallet’ technology, an RFID chip that allows a reusable package to be associated with its owner through an app. The ‘owner’ can then use the package and app to pay and refill the container at Internet of Things dispensers; this is called a ‘digitally verified refill’.
SYSTEMIQ’s Shiran says these companies need more support to scale. “We’re barely scratching the surface of what’s possible. There’s hundreds of start-ups working on really exciting technologies. They need supporting policy and investments.”
Rachel Watkyn from packaging provider Tiny Box Company agrees. “Businesses are not going to readily adopt new solutions without economic benefit, but government grants could help them reach the right price points,” she says, and points out that a plastic carrier bag currently costs 14p, whereas potato starch carrier bags of a similar size cost 58p. “How many businesses will justify a 414 per cent increase in packaging costs?” Watkyn says that supermarkets also need to be willing to adopt the new products.
Driving change in the plastics sector has proved a hard slog. One of the reasons for this, says Laura Peano, global plastics lead at sustainability consultancy Quantis, is that plastic waste has a very low economic value compared to other waste. “That’s why it has a high potential for leaking into the environment,” she says.
‘Plastic credits’ can be part of the solution, Peano suggests. A credit is a transferable unit that represents a specific amount of material collected from the environment, usually in an African or Asian country, that can be recycled. A company using a pallet of virgin plastic, for example, can buy a plastic credit corresponding to the form of plastic being used.
“By providing economic value to the plastic it can push waste collection from the environment for recycling,” Peano explains, but the credits must be “transparent, measurable and independently audited”.
No one knows what a future ‘plastics utopia’ might look like, or if it can even be achieved. There is still much basic work to be done – 43 per cent of the plastic put on the market in Europe is unaccounted for in waste statistics (approximately 22Mt per year), meaning there is surprisingly still a need to understand the problem better. The US, which is one of the biggest plastic polluters globally, has a similar problem. US report ‘Reckoning with the US Role in Global Ocean Plastic Waste’ advocates for a national marine-debris tracking and monitoring system to address such knowledge gaps.
There are no ‘silver bullet’ solutions, says Shiran: “A system-wide approach is needed.
“My main concern is the speed of change. The next three to five years are critical,” he adds. This is because long technology-maturity cycles – a chemical recycling plant built today will still be around in the 2040s – mean decisions made now will determine whether the European plastics system will achieve a circular economy and net-zero greenhouse gas emissions by 2050 in line with global targets.
The new international treaty under development is a milestone to achieving this, but perhaps not yet a turning point, says Peano at Quantis: “There is, quite simply, still so much to do.”
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