Each year, the U.S. generates approximately 300 million scrap tires. While a number of these end up in landfills, the majority of scrap tires are used in a variety of ways, including as ground material rubber to create rubber-modified asphalt.
According to John Sheerin, director, End-of-Life Tire Programs at the U.S. Tire Manufacturers Association (USTMA), the tire recycling industry is in a state of transition. As he explained, there is a distinct trend towards increased utilization of ground tire rubber in new products like molded and extruded goods and landscaping mulch.
“Further growth in rubber modified asphalt is expected,” Sheerin said. “However, continuing movement towards non-solid fuels have adversely impacted tirederived fuel markets that historically have consumed the majority of scrap tires since the 1990s. So, we are seeing a shift towards more material reuse. The last 12 months have seen a return to normalcy after the global pandemic with in-person meetings and compliance inspections resuming. We are seeing more activity.”
Amy Brackin, senior vice president of sustainability at Liberty Tire Recycling, added that in many ways the tire recycling industry is the most complex it has been in the last decade. As she explained, the industry must now balance the demand from retailers and manufacturers to provide the highest and best use of end-of-life (EOL) tires, the further demand from retailers to have timely and dependable end-of-life (EOL) tire services, and the regulatory demands of us as recyclers.
“Balancing these sometimes- competing goals has become a complex equation,” Brackin said.
Reflecting on the last few years and the impact of COVID, Brackin pointed out that it’s been an interesting time for everyone in the industry.
“In early 2020, we saw an immediate drop in tire flow from our customers as a result of lockdowns, which dramatically reduced travel, and therefore tire usage. The balance of the year created a multitude of inconsistencies,” Brackin said. “We navigated the ebb and flow of business openings and closings, quarantines and labor shortages across all industries. By 2021 however, we saw a dramatic increase in the number of tires coming in. People were traveling, primarily by car, with stimulus money to spend. As we entered 2022, we saw things settle into a more ‘normal’ tire flow and regain consistency by the end of the year.”
End markets performed well during this same period. For instance, tire derived fuel (TDF) has been up largely due to rising energy costs. In addition, construction markets boomed. Lawn
and garden products, such as rubber mulch and molded products made from recycled rubber, saw increases due to the number of household projects completed during COVID.
“However, our markets were negatively impacted by inflationary costs to produce and ship goods,” Brackin said. “As we have moved from late 2022 into the first quarter of 2023, we have seen some signs of softening in the crumb markets and expect this to continue through 2024 if current economic forecasts are correct.”
Ongoing Challenges
The biggest challenge facing the scrap tire industry continues to be that the growth in scrap tire generation has exceeded the growth in scrap tire recycling markets. As Sheerin pointed out, while the recycling markets have grown, that growth has not been enough to overcome the continued growth in generation of scrap tires.
“We have therefore seen more tires going to landfills even as ground tire rubber markets have grown significantly,” Sheerin said.
USTMA has focused on circular and sustainable scrap tire recycling markets. The organization has supported infrastructure legislation for many years and the Infrastructure Investment and Jobs Act (Bi-partisan Infrastructure Bill) passed by Congress and signed into law is helping to incentivize circular and sustainable scrap tire markets.
Additionally, according to Sheerin, scrap tire markets can benefit from provisions of the Inflation Reduction Act.
“We are working with stakeholders and states to grow markets for rubber modified asphalt which lasts longer and cracks and ruts less than standard hot mix asphalt and is therefore more
resilient and sustainable,” Sheerin said. The Rubber Modified Asphalt State of Knowledge report USTMA co-sponsored with The Ray (a full-scale highway innovation demonstration laboratory in Georgia) and authored by University of Missouri identified the state-of-the-art for the technology and identified data gaps for additional research.
“We are also working with our partners First State Tire Recycling, Liberty Tire Recycling, and the Tire and Rubber Association of Canada to prepare a Tire Derived Aggregate State of
Knowledge Report by University of Wisconsin. Tire Derived Aggregate is a long lasting, lightweight building material that can be used in retention basins and infiltration gallery to help purify stormwater,” Sheerin said.
USTMA recently send a letter to Congress identifying areas where policymakers can continue to work together including investment in the expansion of sustainable and circular infrastructure solutions for scrap tires, such as use in rubber modified asphalt (RMA) in infrastructure projects and research to assess the benefits of tire derived aggregate (TDA).
From Brackin’s vantage point, she said that typical of most industries, rising fuel costs, increased operating expenses, and labor shortages have hit the tire recycling industry hard, making it impossible to collect and process tires at the same costs as even a year ago.
“Specific to tire recycling, I would say it is finding a consistent balance for outbound material that aligns with quantities being generated. You can’t just decide not to pick up a customer’s used tires when your warehouse is full, or you don’t have demand in your backend markets,” Brackin said. “Retailers also require dependable service that provides sustainable solutions for their used tires. It is a daily challenge across our industry, but expanding end markets can lessen this impact in the future. Hand in hand with that is the challenge of market development. We need growth of end markets for tire-derived material. This comes with collaboration, significant capital investments, and subsidized margins on outbound products to truly displace virgin materials in use today.”
For context, in the USTMA’s 2021 Scrap Tire Management Summary, the data shows that scrap tire recycling is not keeping pace with increased annual generation. In total, markets consumed 71 percent of scrap tires in 2021, a decrease from around 76 percent in 2019.
While this is a concern for such players as Liberty Tire, it should be noted that this is an incredibly high overall recycling rate.
“Nonetheless, there are several factors that drove this decrease on a percentage basis. A passenger tire equivalent, or PTE, is the average weight of a tire,” Brackin said. “This weight has increased by roughly 15 percent over the last decade with the growth of the SUV market and new tire technologies. In addition, the electronic vehicle (EV) market has grown and the heavier load of these vehicles and the higher instant torque, are leading to increased tire wear. Regardless of the reason, we see this as a motive to expand our research, development, and investment into sustainable solutions for EOL tire material. We strongly believe consumer sentiment toward recycling and sustainability will be a key driver to help in this process.”
Continuous Innovations
As of late, Sheerin said technological innovations have not had a great impact on the tire recycling industry.
“No doubt there is tremendous innovation developing in many fields including pyrolysis, devulcanization, wire processing, and other areas, however, the impact on the market as of late has not been material,” Sheerin said. Further, tire manufacturing has tremendous innovation in sustainable and biobased materials, sensor technology, airless tire technology and many other fields. However, it typically takes many years for new tire technology to develop, become widespread and then reach end of life before the impact will be felt in the tire recycling industry.
Liberty has continued to invest significant capital to provide multiple end-use outlets to the industry as this is critical to the long-term success of tire recycling. Brackin stated that Liberty’s goal is to partner with companies that share the company’s vision to move end-of-life tire material up the value chain towards circularity.
So what type of innovations is the scrap tire recycling industry experiencing? Brackin said that in general, she would say the processing industry has become more sophisticated and efficient. Just like in tire production, processing technology continues to advance on all fronts, from plant and collection efficiency to how end-of-life tires get into secondary markets.
“Not long ago, tires were simply shredded and buried. That evolved into processing tires into smaller pieces, but even then it was not really managed with the consistency required by more sophisticated end markets,” Brackin said. “Today, tire recycling has advanced to respond to the needs of those markets and can deliver a highly specialized product, with consistent quality, at sizes so small that they are impossible to differentiate with the naked eye.”
More broadly, tire manufacturers are incredibly focused on sustainability and continue to innovate tires with new technology almost daily. As Brackin explained, some of those changes in raw materials and design have begun to impact the industry and require more engagement between the recyclers, the equipment providers, and the manufacturers, to ensure they are all staying ahead of those trends and can manage them effectively.
In the end markets, the industry is also seeing several emerging technologies that have continued to gain momentum.
“Rubberized asphalt barriers that once required specialized equipment and operators, have been broken down with the introduction of dry mix alternatives that can be incorporated using existing jobsite equipment,” Brackin said. “We are now able to compete in any paving size application, from parking lots to major interstates. These engineered dry mix additives capture all the good performance benefits of rubber modified asphalt, se while being simpler to use in the field. This enables pavement owners to make an impact in terms of longevity, sustainability, and life cycle costs in rubberized asphalt projects. In addition to asphalt, gasification, devulcanization and pyrolysis are all areas we’ve seen much focus on with goals of creating circularity in tires and providing alternatives to virgin carbon black.”
Projected Outlook
From Sheerin’s viewpoint, the scrap tire industry is moving towards recycling markets which are sustainable and circular. This driving force coming from both within and outside the industry as a social objective will have major impacts on how tires are made, used and managed at end of life in the future.
Brackin agreed that the market outlook is very positive. As she explained, end-of-life tires have taken a different position in the minds of tire manufacturers, retailers, and consumers as sustainability is moving more into the day-to-day vernacular of the world.
“As consumers become more educated on the benefits of using end-of-life tires, the only limit in how these tires can be used is the imagination of companies seeking more sustainability in the future,” Brackin said. “The more people think outside the box about the possibilities, the greater the positive impact on the environment and the world around us will be.”
“Movement towards electric vehicles may require more tires because those heavier vehicles and their acceleration characteristics may wear tires faster. This gives us even more motivation to grow the markets for end-of-life tires,” Sheerin said. “As Yogi Berra said, ‘it’s tough to make predictions, especially about the future’. Nevertheless, I’m optimistic that the tire industry will lead the way towards a more sustainable future and a more circular economy.”
