This article appeared in the November 2024 issue of Resource Recycling. Subscribe today for access to all print content.

With slight differences across regions, some 30-40% of global plastics demand comes from packaging production. Low cost and functional properties make plastics an intriguing packaging solution. Yet it comes at a price from a climate perspective: With 90% of global plastics being made from fossil resources, our appetite for wrapping things in plastics takes a toll on the environment. In theory, plastics are well-suited for recycling, but there are various hurdles to turn this theory into practice at global scale, including the need to collect and sort, the limits of existing recycling technologies when it comes to impure, multi-material or layered materials, and demanding and sensitive plastic applications.

Considering the highly valued properties plastics offer and the limited availability in many cases of alternatives at scale, there is a wish to continue using them. Yet the question will be how can we make plastics production, use and waste management more sustainable. In parallel to recycling, do we have options to move from fossil-based to non-fossil based solutions?

I am convinced that there is reason for hope.

If it can be recycled, it should be recycled

Our priority should be to recycle whatever can be recycled. On the one hand, existing mechanical recycling has to be expanded. Whenever mechanical recycling can be done, it should be done. However, the aforementioned limitations of mechanical recycling lead to the need for new recycling technologies such as chemical recycling. Thus, whenever mechanical recycling is not feasible, for example due to waste streams being too mixed or impure — or the final products being too demanding quality-wise — chemical recycling can close the gap. A lot is happening in this regard.

At Neste, we are ourselves currently investing in chemical recycling capabilities at our refinery in Finland, focusing on turning liquefied waste plastic into high-quality raw material for new plastics, but other companies are also pushing new recycling technologies. Chances are good that this will enable us to increase recycling of plastics including plastic packaging in the future. But a question will remain: Will recycling be enough? Unfortunately not.

Demand for plastics and packaging is increasing at global scale. Aside from that, collection, sorting and recycling aren’t perfect processes. They come with material losses. Thus, even at a recycling rate of 100% (and we are currently only at some 10% globally!), we wouldn’t be able to meet the demand for new plastics just through recycling. Meeting the demand will require us to tap into other (renewable) material pools — and one of these is biomass.

Biogenic carbon is available in large quantities as a more sustainable feedstock

Plastics made from bio-based materials aren’t new, and there is a broad range of different approaches and technologies to turn biomass into polymers. They all share one basic concept and a common advantage, though: using biogenic carbon instead of fossil carbon, and as a result reducing greenhouse gas emissions over the lifecycle of plastics.

So let’s focus on the route of using bio-based waste and residues to achieve that goal, as this is also what we at Neste are experts on. Initially, we used these materials — for example, used cooking oil or residues from vegetable oil production — to produce fuels like renewable diesel or sustainable aviation fuel. We still do so, but the renewable hydrocarbon products our refineries produce can also be used to replace fossil naphtha or propane in the production of plastics. In fact, bio-based waste and residue oils and fats can be used to produce a one-to-one replacement for fossil plastics feedstock that can also be used in a blend with fossil feedstock. The plastics and chemicals produced that way are just the same as those made from conventional fossil raw materials, be it common polypropylene or polyethylene, PET or similar.

This is why we call it a drop-in solution: same performance, same characteristics, different raw material, different carbon footprint. The difference in the carbon footprint can be quite significant. Replacing fossil feedstock with bio-based feedstock may see GHG emissions plummet by more than 85% over the plastics’ lifecycle.

The question of scalability and availability

Plastics made with bio-based materials are not a vision but a reality already today. Neste alone — and we are not the only ones active in this field — has a production capacity for renewable products of 6 million tons, set to grow to 7.5 million tons within the next three years. Other providers are increasing their capacities as well, so there are good chances that bio-based materials can contribute to the defossilization of plastics, and thus plastic packaging, at industrial scale.

While production capacities are one thing, the required raw materials are another. The amount of commonly used waste and residue oils and fats is finite. Experts predict that the global availability of such resources could exceed 44 million tons annually from 2030 onwards. Considering the current global plastics production is somewhere around 440 million tons, this limited supply highlights a significant gap. Furthermore, it’s important to acknowledge that these oils and fats are not solely designated for plastics production; they are also utilized in manufacturing fuels and other products, emphasizing the need to explore alternative solutions. This means that further renewable carbon pools will be required. Research and development efforts are looking at various options for that, including algae, lignocellulosics or so-called novel vegetable oils, which are vegetable oils that do not compete with food and animal feed production and feature regenerative agricultural concepts. Aside from these bio-based options, a long-term alternative is Power-to-X, which converts CO2 and green hydrogen into hydrocarbons.

The time is now to pave the way for defossilization

The next years will be decisive to enable a future for fossil-free plastics and plastics packaging. New recycling solutions like chemical recycling are in a commercialization phase, and now is the time to ramp them up. While already available in large volumes, bio-based materials need to be incorporated at a broader scale throughout plastics production. These will be decisive factors to ensure that alternative solutions, on top of mechanical recycling, can play their role in defossilizing the industry in the long-term. I am confident it can be done.

Maiju Helin is head of market development for polymers and chemicals at Neste. Previously, she was head of sustainability and regulatory transformation and of stakeholder management for Neste’s Renewable Polymers and Chemicals business. Prior to Neste, Maiju worked at UPM Biofuels in various roles.

The views and opinions expressed are those of the author and do not imply endorsement by Resource Recycling, Inc. If you have a subject you wish to cover in an op-ed, please send a short proposal to [email protected] for consideration.

This article appeared in the November 2024 issue of Resource Recycling. Subscribe today for access to all print content.

Tire recycling, by and large, means chopping up tires and doing one of two things with the pieces: using them as-is, such as in mulch or artificial turf pellets, or burning them for fuel. But these traditional markets haven’t been keeping pace with new tire generation, according to the latest data from the U.S. Tire Manufacturers Association, an industry advocacy group. And researchers, public officials and others across the country are working to push tire recycling in new directions, including into the same roads those tires once traveled.

More than 3.8 million tons of used tires were processed into usable products in the U.S. in 2023, a 79% diversion rate, according to the association’s biennial End-of-Life Tire Management Report, the newest version of which was released in October. The figure was an uptick from 71% two years prior but was also the exception topping off a decade of decline from the peak of 96% in 2013, according to the association’s previous data.

John Sheerin, the organization’s senior director of end-of-life tire programs, said the bump was likely from temporary factors. The dip in miles driven at the height of the COVID-19 pandemic, for instance, meant a dip in used-up tires to manage, and higher natural gas prices resulting from Russia’s war on Ukraine made tire-derived fuel more appealing for furnaces, paper mills and similar facilities.

Barring these blips, U.S. tire consumption rises ever upward, Sheerin said, and the tide is against carbon-emitting fuels like TDF and the coal it often supplements. The problem requires development of end markets like rubber-modified asphalt, an association priority that has been gradually drawing more support at the state and federal level.

“We have a ways to go,” Sheerin said. Still, “a lot of things are going in the right direction, and there’s a lot of energy in the field right now.”

Street-level work

Used tires are of course a universal issue, often the biggest class of material collected by weight for the local programs that accept them. States from Alabama to California devote millions of dollars to grants and other programs for tire management, like the $2 million awarded by West Virginia to 22 businesses and local governments early this year. Connecticut in 2023 passed the country’s first statewide extended producer responsibility law for tires, which state officials expect to go into practice next year.

In Tennessee, state officials have taken deliberate steps to grow the used-tire supply chain, said Chris Pianta, an environmental program manager for the Department of Environment and Conservation’s Office of Sustainable Practices.

Since 2015, a small fee on new vehicles has gone into the Tire Environmental Act Program, which awards yearly grants for a mixture of private and public organizations. To build options and lower transportation costs, the first several years’ grants focused on increasing the number of local tire processors, Pianta said. The state has since gone from just one processor to half a dozen.

“I think we’re definitely in a better spot than we were nine years ago,” he said, noting that the grants over their history have contributed more than $10 million to 30-plus projects that diverted 7.6 million tires. “Hopefully we’re starting to make a dent.”

One such processor was Memphis Tire Recyclers, which started in late 2021 after its founders saw an opportunity in addressing hoarded and illegally dumped tires around the city, said Corteney Mack, its chief business officer and co-owner.

Memphis Tire received more than $460,000 from the state grant program in 2022 to buy equipment and facility upgrades, in some cases years earlier than the owners originally planned. The business now has three locations and customers buying all of the crumb rubber, tire-derived aggregate and tire-derived fuel it can make.

“It definitely helped take our business to new heights quicker than we anticipated,” Mack said.

Now Tennessee’s grant program has diversified into more, smaller recipients with projects that directly use scrap tire products, Pianta said. The bulk of this year’s $1.6 million in grants went to tire-rubber trails at state parks and other public areas, for example. Another $147,000 went to a Memphis nonprofit called the Binghampton Development Corporation to install bicycle lane barriers along 6 miles of city streets.

The BDC works to build job skills and work experience for communities in need, such as those with histories of substance abuse or with the criminal justice system, said Andy Kizzee, director of the BDC business hub. The organization has been around for two decades, but over just the past few years it has partnered with the city of Memphis, local professionals and others to recycle a variety of challenging materials. The push all began about three years ago with the confluence of two community problems.

“Memphis has the second-most pedestrian and bicycle deaths in the country, and we’ve got a huge illegal dumping problem,” Kizzee said. So a local urban planner, Laura Murray, partnered with a local industrial artist, Tad Pierson, and with the BDC to try to help both problems at once by converting dumped tires into barriers shaped like camelbacks, upright panels or three-leafed clovers. The barriers are bolted directly to the pavement and alert drivers if they start crossing the line.

Grants from the state tire program, the nonprofit People for Bikes and elsewhere funded a 1-mile pilot in 2022, and now the project is ready for another leap that’ll start in January, Kizzee said. And it will reach beyond dumped tires to make a bigger dent in the tire issue.

“We’ll be sourcing those from tire shops — small mom-and-pop tire shops that wouldn’t necessarily have a contract with a hauler or tire processor,” he said.

Into the asphalt recipe

Tennessee’s approach has also touched on a relatively small but growing trend toward rubber-modified asphalt, a type of pavement that incorporates finely ground tire rubber as an ingredient. The resulting mixture can extend road lifespans, reduce repair costs over time and bring other benefits, according to a state-of-knowledge report released in 2021 by the tire manufacturers association, the University of Missouri and The Ray, a nonprofit pushing for more sustainable transportation.

The technology has been the subject of testing in multiple states, including on several hundred miles of roads in Alabama, Georgia and Michigan. The University of Tennessee-Knoxville received a state grant of about $350,000 in 2023 for similar research.

A small sliver of old tires, about 3%, was used for asphalt applications in 2023, according to the manufacturers association report released in October. But the nation’s highways and roads represent a massive possible end market for the hundreds of millions of used tires generated every year, said Baoshan Huang, a professor in UTK’s Department of Civil and Environmental Engineering who’s overseeing the tire research project.

“The biggest potential application is to put it into asphalt pavement,” he said. “Our society, our community, does have a need to utilize this waste tire rubber, and also there are technologies that can use it more effectively.”

UTK is partnering with the state Department of Transportation to test the asphalt on sections of roads, developing mixtures and experimenting with such details as how much to de-vulcanize, or essentially cook, the rubber to get the best results.

It’s a common topic of research across the country, since every state sets its own pavement specifications and has its own climates and other concerns, said Sheerin with the manufacturers association.

“You can’t just throw some rubber in there and say it’s good,” he said. “They want to see work on the ground in their state that has lasted for some time.”

Sheerin reiterated the many potential benefits to rubber-modified asphalt, including its durability and its ability to be recycled multiple times as roads are resurfaced. The Tire Recycling Foundation, which works in concert with the association, received $3.8 million from the U.S. EPA in July as part of a round of grants supporting low-carbon manufacturing. The money is meant to help develop robust environmental product declarations that show environmental impacts across the life of a product, which could help spur more widespread adoption of the technology.

“At present it’s a relatively small market,” Sheerin said, “and it needs to grow substantially.”