Tire recycling in the United States is the disposal and reuse of waste tires.
Uses
Several forms of waste disposal and reclamation have been put into place, using waste tires as both commodities (new tires) and a form of energy (fuel alternative).
According to the Rubber Manufacturers Association (RMA), as reported elsewhere, 52% of scrap tires are burned for fuel 12% are used in crumb rubber products 16% are used for civil engineering applications at least 14% are ground and dumped in landfills. Different agencies in the world are now recycling waste tires and other rubber goods into useful products instead of polluting the environment.
Whole tires can be used for a number of applications, including artificial reefs, breakwaters, erosion control, playground equipment, and highway crash barriers.
Waste tires are made of a material which can have another economic use. This means that tires which are no longer suitable for use on vehicles due to wear or damage, can be recycled to serve a new economic purpose (rubber asphalt and concrete, fuel alternatives, carbon sources, etc.).
There are many different uses for waste tires that are beneficial in helping reduce the amount of waste tires in stockpiles. Recycled tires are used in creating synthetic turf in sports arenas. Synthetic turf is made up of Crumb rubber which is recycled rubber from automotive or truck scrap tires. Waste tires are also used to make rubber mulch which is used in gardens and playgrounds. Waste tires have also been known to be used in making track and field pavements, roads, and shooting targets. Recycled waste tires have several recreational uses. They are used for tire swings, flower pots, compost bins, retaining walls, and sandals in developing companies. They can also be used as fuel energy. Waste tires used as fuel are either shredded or whole, depending on the combustion device being used. Fuel produced from waste tires is known as Tire-derived fuel (TDF).
There is a potential for using waste tire rubber to make activated-carbon adsorbents for air-quality control applications. Such an approach provides a recycling path for waste tires and the production of new adsorbents from a low-cost waste material. Also, recycled rubber from tires is used as a component of various products commonly known as "tire derived products". Such products include asphalt paving mixtures and as extenders in a variety of rubber products such as roofing materials, walk pads, carpet and flooring underlay and other products. More such products are being developed.
Processing
To convert the waste tire into a valuable product, it must first be reduced in size and then recycled. The recycling process begins first by shredding tires into small manageable chips, which are then cooled to cryogenic temperatures, causing them to become brittle. They are then pulverized into a material that must be screened to remove large chunks of rubber or polymer. Finally, the remaining fibre and magnetic material are separated from the pulverized material using a magnetic separator and a vibrational separator. This form of recycling is environmentally friendly, and allows a valuable resource to be used again and again.
Disposal
In 2007, around 300 million tires were scrapped in the United States. In 2008 around one billion tires were being scrapped each year with an estimated further four billion already in stockpiles and landfills. Global production in 2008 was about 1.5 billion new tires. The U.S. alone produced 291.8 million tyres in 2009 as estimated by the U.S. Rubber Manufacturers Association. In 2013, of tires were generated in the U.S. Newer figures (2015) talk about 450 million scrap tires generated annually in the U.S.
The United States disposes of 279 million waste tires each year, representing over 4 million tons of scrap waste. The polymeric materials that tires they are made of do not decompose easily. Even after heavy use and wear, only a few grams are abraded from each tire before they are deemed not serviceable. This means that almost all the material is discarded, and a valuable resource is left to become an environmental pollutant, if dumped.
Environmental issues
Waste tires are generally discarded after only a small amount of rubber is worn away. Even so, these tires are unfit for further use in the vehicles they were made for. At the same time they are also unwelcome in landfills and have been proven to be an environmental threat.