Same Tired Story

Throughout the 1980s and 1990s, grants have been funneled from the federal government to and through states to fund tire disposal, recycling and reuse projects. Thus far, no “magic bullet” has been found that offers an end market for scrap tires that is so attractive that discarded tires can be considered a desirable commodity. But a number of smaller end markets are being developed, yielding the hope that a cumulative effect could be building that would make the tire disposal problem a thing of the past. 

BURNING RUBBER

Not long ago, tire-derived fuel (TDF) was considered the most promising end market for scrap tires—and it still may be. But market conditions have not favored TDF becoming an instantly competitive force within the energy market. 

This decade has seen oil-producing nations ship petroleum in record amounts at a very favorable price for energy-consuming nations. Similarly, overcapacity is a word often used to describe the amount of energy available from America’s electrical power plants. “For the last ten years, there hasn’t been a need for most companies to explore alternative fuels,” says Robert H. Davis, president and CEO of Greenman Technologies Inc., Lynnfield, Mass. 

But in the regulated utility market, the price paid for electricity has varied widely from state-to-state and region-to-region. This created the opportunity within some states—sometimes aided by subsidies—for TDF to gain a foothold at some power plants and a few manufacturing facilities. 

“The three largest consumers of TDF are utilities, cement kilns and paper mills,” says Greenman’s Davis, whose company has been attempting to consolidate the tire shredding and TDF production industries in what it considers to be key regions of the country. 

“This industry is very ripe for consolidation and growth—someone to professionalize the industry,” says Davis, who was formerly a manager in BFI’s recycling division. When he was with BFI—at a time when its recycling division was a $700 million part of the company—Davis says he “thought tires could add another $100 million” to its revenues. 

He left BFI in 1997 when the company “had tire operations that were successful there, but BFI was not going to pursue them,” says Davis. He agreed to take over the reins at Greenman and shifted the company’s focus away from experimental end markets (such as an injection molding process using a plastic/scrap tire blend) to the making of crumb rubber, primarily for TDF end markets. 

The company acquired BFI’s tire recycling facilities, then two facilities it bought from Republic Industries, and it has purchased additional independent tire shredding operations. 

Davis acknowledges that a phasing out of subsidies in California for tire-derived fuel use has hurt the end market for TDF. “But about 115 and 135 million tires a year are still used there; it’s still the lion’s share,” he remarks. 

Greenman’s strategy has been to stay close to that market. “The appetite [for TDF] is better in the southeastern United States,” says Davis, whose company operates tire recycling plants in Georgia, Mississippi and South Carolina. Additionally, the company has three facilities in Minnesota. 

In the South, Greenman ships TDF to facilities operated by such customers as Inland Paper, Mead Paper, Blue Circle Cement and the Tennessee Valley Authority. While TDF may be an alternative fuel, Davis says that does not make it an inferior fuel source. 

“There are two-and-a-half to three gallons of petroleum in each tire,” says Davis. “It can burn cleaner than coal if it’s processed right,” he remarks. Davis notes that there are steps that have to be taken by TDF users. “They do need feed or metering equipment added to the boilers,” he says. “They need to comfort themselves to make sure it can be burned clean and meet clean air guidelines.” 

Barring dramatic shifts in the market, TDF will remain the largest market for scrap tires for some time to come. A summary of scrap tire markets presented by Michael Blumenthal of the Scrap Tire Management Council, Washington, shows that TDF applications consumed more than ten times as many scrap tires as any other single market. 

“There are sometimes comments heard that scrap tires have much more valuable uses than to be used as fuel or in some civil engineering applications,” Blumenthal noted in a presentation to the Institute of Scrap Recycling Industries Inc. “However, if the goal is to find sound markets for all scrap tires, the reality is that we will need all markets, including fuel and civil engineering. There are more than enough tires to go around for ground rubber or for any other economically viable market,” he added. 

Specifically, the U.S. produces 3.3 million metric tons of scrap tires each year, which could theoretically be ground into 2.3 million metric tons of crumb rubber. “The current market for ground rubber in all applications is about 108 million kilograms, or about 5% of the total potential volume,” Blumenthal stated. “In order for the ground rubber markets to consume all of the potential scrap tire-derived ground rubber, the markets would have to increase more than 20 times.” 

ALTERNATIVE MARKETS

Although tire-derived fuel remains the largest market for scrap tires, it is far from the only one. 

Both tire recyclers and manufacturers continue to seek end markets for the rubber, steel, fiber material or mixed material product that results from ground and shredded tires. Some civil engineering applications have also been found that employ whole tires, often after they are baled or compressed. 

Rumber Materials Inc. (RMI), Austin, Texas, is one company that is finding markets for crumb rubber made from scrap tires. According to J’Lynn Hare, general manager of RMI’s Munster, Texas, plant, the company is consuming 650 tons of scrap tires per year. This year, the company will mix that amount of crumb rubber with 450 tons of scrap plastic to make Rumber Composite, a granular product that can be used to make polymer products “stronger, much more impact-resistant and longer-lasting,” according to RMI. 

“Tests showed that by using Rumber composite, our buckets were more resistant, especially in cold weather, as far as cracking, pliability and durability goes,” says David Bowell, president of Miller Manufacturing, a St. Paul, Minn., maker of injection-molded buckets. 

Other customers RMI has found for its product include makers of highway signs, livestock feeders, plastic pallets, trailer bed floors, and dumpster and garbage pail lids. “The Rumber composite can act as an impact modifier for a myriad of polymer products,” says Harold Fischer, president and CEO of RMI. 

The company has recently completed a 10,000 sq. ft. expansion of its plant, according to Hare. She feels many more uses for the composite will be found. “We’ve just now seen the tip of the iceberg,” says Hare. “There are so many places and so many uses that we haven’t thought of.” 

One end use for scrap tires that has been thought of—and occasionally put into place—is within a paving material mixture. While “rubberized asphalt” has demonstrated itself as a usable material, at least as far as its advocates are concerned, it faces competition from a number of other recyclable commodities that are trying to find their way into paving mixtures. 

Foremost is recycled asphalt and concrete itself, which is more commonly used as road base or in off-highway applications. But glass cullet producers have also pushed for the use of “glassphalt,” and newer mixtures have been made using ground ceramics and even ground plastic computer components diverted from the waste stream. 

Despite the competitive aggregates/paving market, rubber recyclers are still concentrating on rubber asphalt as a potential market. The Tire and Rubber Recycling Advisory Council (TRAAC) of the International Tire and Rubber Association (ITRA), Louisville, Ky., is holding a workshop at its annual meeting to address the topic. The ITRA convention is taking place in Nashville, from June 9 to June 12. 

“A Road Map for Introducing Asphalt Rubber in Your State,” will include a tour of a section of road in Tennessee that was paved with rubberized asphalt. Arizona has been the state at the forefront of using rubberized asphalt, while Tennessee and Texas have been among the states to recently solicit and accept bids from contractors using the material. 

“Last fiscal year we spent $18.4 million on products containing crumb rubber,” says Rebecca Davio, recycling coordinator for the Texas Department of Transportation (TxDOT). “The majority of that went to rubberized crack sealer and chip seals, or seal coats,” she notes. “We also are using some rubberized asphalt, and a recent project near Odessa, Texas appears to be successful.” 

Davio believes there is a good chance the use of rubberized asphalt could spread beyond the project in the Odessa TxDOT region of the state. “My guess is that it probably will spread,” she says. “Every district and every project has to be looked at to see if it has the right conditions that would make the best use of this material. The good experience, though, should certainly help them want to consider. There are a couple of projects going up for bid in the Odessa region and in the Abilene area” 

For state governments, the incentive is certainly there to encourage end markets for scrap tires. “Tires provide such an abundant stream of material,” says Davio. 

Blumenthal says bluntly, “The United States faces a major challenge in dealing with scrap tires.” In his remarks to ISRI, he noted that the U.S. “generates approximately 273 million scrap tires” each year, a number that increases annually. To add to the problem, tire stockpiles found throughout the U.S. could contain as many as 850 million scrap tires. 

In addition to rubberized asphalt, states have been experimenting with other ways to use scrap tires in civil engineering applications. The Northwest Arkansas Regional Solid Waste Management District, Harrison, Ark., has been using whole or baled tires in several different ways, according to program director Bill Lord. Lord also tracks projects taking place in other states using scrap tires. Among those projects and uses: 

• Erosion control along a river bank and lake shore in New Mexico. More than 2,500 bales of tires were wrapped in wire and then encapsulated in cement along the Pecos River and the shore of Lake Carlsbad in New Mexico. 
• Land reclamation in low lying areas in Louisiana and Alabama as well as in old pit mines in Arkansas. 
• Road buttresses to prevent trucks from driving into a deep pit mine in Arkansas. 
• Animal fencing for a corral. 
• Firing range construction.

But while the products have been well received, the conclusion seems to be that the total market for such products is not large enough to put more than a small dent in the oversupply of scrap tires. 

PIONEERING ON THE PROCESSING FRONT

The difficulty and high cost of effectively separating the different materials found in tires—rubber, steel and fiberglass—has been cited as the primary hurdle to creating a demand-driven market for the scrap commodities found within tires. Steel belting that has too much rubber or fiberglass attached, for instance, is not desirable for steel mills melting scrap. 

Can advances in the processing of scrap tires change that equation? There are still researchers and entrepreneurs willing to find an answer to that question. 

Terence C. Byrne, chairman and CEO of Tire Corp., Montreal, believes there are serious processing advances to be made, and that his company has made a giant step forward. 

“Others have taken existing size reduction equipment and adapted it to tires,” says Byrne. “When we took a look at what results from those, the product is just not 100% clean. There is a lot of commingling, whether you reduce to powder or whatever,” he adds. 

“We felt we had to design a system that would deal directly with a tire,” Byrne continues. “We realized we had to separate the sidewalls from the treads. They contain different types of rubber, different mixes of materials, they can be different colors.” 

Byrne says markets exist for everything produced by the Tirex process. “The fiber is in string form. Certain molding companies use it to reinforce rubber or for large O-rings. Plastic lumber makers are using it, and paying about 25 cents per pound (U.S.) for it.” The steel is clean enough to be purchased by scrap dealers. 

For crumb rubber produced at Tirex’s Montreal plant, “we’re getting 10 to 15 cents per pound for 10 to 20 mesh, and 15 to 20 cents for 20 to 30 mesh,” says Byrne. “Depending on the price, we can move everything we make,” he adds. 

As is the case in most of North America, procuring feedstock has not been a problem for Tirex. “All tires are provided by RecyQuebec,” says Bryne. “When you recycle to crumb rubber, they provide a subsidy.” 

Byrne says, though, that he is setting up the company as one that can operate in a market without those subsidies. “You’ve got to be able to compete without the subsidies.” 

Part of that plan for Tirex involves selling the company’s patented TCS-1 plants to other tire recyclers. Byrne says he has 14 contracts for plants to be built over the next four years. The buyers “sought us out—we really have done almost no sales effort at all.” He says the response is encouraging, especially since Tirex “put $8 million into the development of this system.” 

EnTire Recycling, Nebraska City, Neb., is trying to secure processing success through high volume as well as by producing high-quality end products. The plant is capable of processing two million tires annually. The company uses a system designed and made by Shred-Tech, Cambridge, Ontario, Canada. Further cryogenic processing produces a crumb product that EnTire is currently selling for 10 to 19 cents per pound. 

HOPE, BUT NOT WILD OPTIMISM

Scrap tires are still considered a disposal problem far more than they are a marketable commodity. 

And while the hope of finding a breakthrough processing solution is now regarded as wishful thinking for alchemists by many in the industry, some gains have been made. Perhaps the acknowledgement that turning scrap tires from garbage to gold was too tough of a target has left the research in the hands of people willing to take smaller steps toward solving the scrap tire dilemma. 

Those involved in this research remain hopeful that the tide can be turned, and the era of scrap tires as a public nuisance can draw to a close. 

“Right now a vast majority of tires are being utilized either in feedstock or as fuel,” says Byrne. “As the feedstock becomes valuable, you’ll see a shift in recycling away from chips and toward the crumb market. I think in a number of years, when you are able to produce in volume a good product, a lot of the subsidies will go away, and scrap tires will have a value. I think that’s even within the next ten years,” he states. RT