Americans generate 250 million scrap tires each year—one for every citizen.
In 1995, 69% of all tires generated were recovered; a 26% increase from
1994. Fewer tires were sent to landfills or stockpiled in 1995 largely
resulting from a growing technology known as Tire Derived Fuel (TDF), which
burns shredded tires for energy that can be used by electric utilities,
pulp and paper mills, and cement kilns. Increased demand for scrap tires
provides a promising outlook for tire reuse and recovery, which will help
decrease the number of tires illegally dumped and stockpiled.
Despite significant strides in recovery rates, tires are still stockpiled
or illegally dumped. Tire piles can create many problems. (Disease-carrying
rodents and mosquitoes thrive in the standing water of tire piles and use
them as breeding sites, creating a public health hazard.) Tire piles are
also a hazard because, if set afire, they are difficult to extinguish and
under uncontrolled conditions, create air, ground and water pollution.
In response to the health and environmental hazards associated with
stockpiled and illegally dumped tires, 47 states have passed scrap tire
regulations mandating the proper management of tires. Many states also
charge disposal fees of $1-$3 when replacement tires are purchased to eliminate
stockpiles and help fund alternative management methods. Since tires often
rise to the surface of a landfill due to the resiliency of the rubber,
many states require tires to be shredded or split before they are landfilled.
Though they take up less space when shredded, tires can be difficult and
expensive to shred due to their steel belts and tough design. Some states
completely ban tires from their landfills to encourage other uses.
Tire Derived Fuel
Scrap tires have historically been a big challenge for solid waste management.
Tire-Derived Fuel (TDF), however, is playing a large role in meeting the
challenge. In 1995, 130 million tires were burned for energy according
to the Scrap Tire Management Council (STMC). As a petroleum by-product,
tires have an energy value nearly equal to oil, and 25% higher than coal.
Recent reports have shown that TDF is comparable to fossil fuel and, in
many cases, burns cleaner and cheaper than coal. It also has a higher heating
Industry is seeing the opportunities in TDF and the market for scrap
tires continues to expand. Shredded tires are used as a fuel in dedicated
tire-to-energy facilities, in pulp and paper mills, and in cement kilns.
Today, approximately 38 cement kilns burn tire-derived fuel; only 2 cement
kilns used TDF in 1990. The high temperature inside a cement kiln provides
for the complete combustion of tires, without black smoke and odors that
are normally associated with uncontrolled burning tires, according to the
Tire Derived Fuel Markets
80 million consumed as fuel 38 cement kilns burn TDF (only
2 in 1990)
Other areas of research and development include pyrolysis and gasification.
The goal of both technologies is to convert tires into fuel gas and oil
with a marketable residual char (carbon black) and steel. Research has
been conducted in this area since 1965, but there has been no successful
commercial application for the technology to date. While the char is not
as suitable in the tire industry, it is suitable as a solid powder fuel.
14 kilns are testing
15 paper mills burn TDF
16 industrial plants including utilities burn TDF
2 whole-tires-to-energy plants
Reuse of Tires
Scrap tires are extending their lives through a variety of uses. Product
research and business development will continue to increase the number
of scrap tires diverted from the waste stream. According to the Recycled
Products Guide newsletter, a company in North Carolina takes worn racing
tires and makes everything from doormats to jewelry. Another in Washington
state has designed products made from used tires to maintain hiking trails
and reduce soil erosion. Its products are being used in a number of national
forests around the nation.
There are many other examples of practical, effective uses for discarded
Highway and road applications is another use that states are using to manage
scrap tires. "Rubber asphalt" is made by blending crumb rubber with asphalt,
with the rubber comprising up to 25% of the mix. California, Arizona, and
Florida use crumb rubber in many of their road projects.
Filler in new tires
Molded goods and manufactured parts
Fish habitats, erosion control, playground equipment
Landfill cover, composting medium drainage systems and absorbent
As markets for scrap tires continue to expand across the country, communities
and tire retailers will find it easier to manage tires generated in their
community. Innovative ideas for the reuse of scrap tires indicate the potential
for diverting an increasing number of tires from the waste stream and recovering
the millions of illegally dumped and stockpiled tires.
"Recycled Products Guide 'Reporter'," 1995
The Goodyear Tire & Rubber Company
The Scrap Tire Management Council
"Scrap Tire Users Directory," Scrap Tire Management Council, 1995
"Burning Tires for Fuel and Tire Pyrolysis: Air Implications," EPA
- 450/3-91-024, 1991
"Scrap Tires: A Resource and Technology Evaluation of Tire Pyrolysis
and Other Selected Alternate Technologies," EGG-2241, U.S. Dept. of Energy,
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