HILTON HEAD, S.C.—By their very nature, off-the-road tires are difficult to manage and recycle, according to a speaker at the 34th Clemson University Global Tire Industry Conference.
But new initiatives are making OTR tire processing and recycling both more feasible and more profitable, increasing sustainability within that market, said Richard Gust, president of national account sales and director of government affairs for Liberty Tire Recycling L.L.C.
The OTR tire market is a fast-growing sector in the tire market, Gust said at the conference held April 18-20 at Hilton Head. OTR sales totaled $5.34 billion globally in 2017, and are expected to grow to $7.68 billion in 2025, he said.
Mining, earthmover and forestry tire sales will continue to grow, and the development of a U.S. infrastructure bill holds significant promise for further growth, according to Gust.
"OTRs represent just 1 percent of the tire industry in unit volume, but 15 to 20 percent in total weight," he said. "As tire industry professionals, we must improve the recovery of these valuable resources to become more sustainable."
Fortunately, the tire recycling industry is beginning to address this issue, according to Gust.
The large OTR tire market presents major challenges through their sheer size, he said. Some 300,000 large OTR tires are manufactured each year, ranging from 300 to 14,000 pounds, he said.
Construction tires (25 inches or below) represent 77 percent of the large OTR tire market, Gust said. Aggregate tires (29 to 49 inches) comprise 15 percent, and mining tires (51 inches and up) 8 percent, he said.
"Note that the mining segment of 8 percent represents 45 percent of the scrap tires by weight," he said.
OTR tires can be repaired or retreaded multiple times, greatly extending their service life, according to Gust.
Retreading an OTR tire costs 30 to 50 percent as much as a new tire, but lasts more than 80 percent as long, he said. Retread plants produced an estimated 615 retreaded OTR tires daily in 2017, he said.
OTR tire recyclers face significant challenges and capital expenditures, Gust said. Transportation and handling costs, processing equipment, trained employees, sustainable markets, safety and a processing space large enough to accommodate giant tires are all major issues in OTR recycling, he said.
"You have to be really concerned about safety when a tire weighs 14,000 pounds," he said.
Loading and unloading equipment is necessary for OTR tire handling, as are special width permits for transportation, according to Gust.
There is equipment to cut and shred the tires and to remove the beads, he said. "Removing the beads prolongs shredder life and delivers a recyclable, high-quality, high-carbon steel," he said.
According to a February 2016 study commissioned by Ontario Tire Stewardship, rubber yield from OTR tires varies from 43 to 71 percent.
Steel recovery ranges from 9 to 57 percent, with industrial tires carrying the highest amount of steel, he said. Fabric yield can be as high as 32 percent, but giant OTR tires contain zero fiber, Gust said. Some major state efforts to recycle OTR tires include:
- Massachusetts: F&B makes dock bumpers, rollers, blades and bucket wear pads;
- Michigan: Entech makes playground material, tire-derived fuel and tire-derived aggregate;
- Minnesota: Liberty Tire makes TDF, TDA and ballistics material for the FBI;
- South Dakota: Wenzel Construction makes livestock water tanks, bale feeders and barn scrapers; and
- Utah: Western Tire makes mulch and livestock water tanks.
Pyrolysis appears to be a common theme in OTR tire recycling, according to Gust. OTR tire recyclers in Canada, Latin America, Australia and South Africa are either using a form of pyrolysis or considering the process, he said.
Titan Tire Reclamation Corp. in Fort McMurray, Alberta, uses a proprietary thermal vacuum process that it claims can recover 500 gallons of renewable blend oil, 4,000 pounds of carbon black and 2,000 pounds of steel, Gust said.
"The U.S., Canada and global mining industries have undertaken green initiatives which include cleaning up waste and discarded tires from mine sites," Gust said. "But a lot more needs to be done."
While current federal policy allows the disposal of solid waste on federal land, the U.S. Bureau of Land Management continues to review this policy, according to Gust.
The Bureau of Land Management and the U.S. Forest Service are conducting research on available alternatives to tire landfilling, Gust said. Meanwhile, the U.S. Environmental Protection Agency continues to define discarded tires as a solid waste, he said.
"Out west in the U.S., we can and we must do better than this," Gust said. "Far too many OTRs are found in vacant desert lots along major highways, while others are buried or abandoned in mines."
Extended Producer Responsibility laws have been either drafted or promulgated in many parts of the world, according to Gust.
"If you are a manufacturer or importer of OTR tires, an EPR program puts all responsibility—financial, operational, reporting, all of it—on you," he said.
There are well-established markets for products made from recycled OTR tires, according to Gust.
"However, if we are going to increase the level of OTR recycling, we must stop stockpiling and burying," he said. "Investments in processing equipment, technologies and markets are necessary if we are to advance sustainability.
"If we don't step up and take care of this, the government will step in and require EPR or something similar," Gust said.