According to the U.S. Department of Transportation 62 million registered vehicles are on the roads in the United States. Multiple that number by four and that is 248 million tires. Yes, a small percentage of the 62 million registered vehicles are motorcycles, but that’s still a lot of tires.
Tire life is being prolonged by tire manufacturers experimenting with better rubber compounds and something called camber tire shaping, which enhances wheel alignment and reduces wear and tear. This has helped reduce tire waste. But when a car’s tires have worn down the treads to where it is not safe to drive, the tires need to be replaced. Because of this, tire recycling has become a big business.
A Big Business
Tires are non-biodegradable and can take up lots space in landfills. Tires can also trap methane gases which damage landfill liners put in place to keep landfill contaminants from polluting the surface land and leaching into ground water sources. So, to prevent as many tires as possible for ending up in landfills, tires are run through a tire recycling machine into rubber pellets. Here are several of the uses for recycled tires.
Ground up tires are recycled into hot melt asphalt and recycled asphalt pavement. Recycled tires are being used for new tires, but only 5 percent by weight of a new tire can be recycled material due to reduced tread life and lower traction. Recycled tires rubber pellets are laid in landscaping beds and gardens as bark mulch. The rubber is ideal to hold in moisture and to block sun to prevent weeds from growing.
In a cement manufacturing plant, old tires have been used as an alternative fuel to produce cement. And recycled tires have even been used in the production of sandals. Recycled tires have been used in the formation of rubber-molded products such as carpet padding, floor underlayment, flooring materials, dock bumpers, patio decks, railroad crossing blocks, livestock mats, movable speed bumps, and the list goes on.
Tire Recycling Process
Tire recycling begins with the steel support rings being removed from the tires. Next the tires are ground up into smaller pieces in a tire recycling machine and come out as ground pellets. Then the ground pellets are shipped to be formed into the various products mentioned above.
To process alternative fuels, in a tire recycling machine, tires are recycled by heating shredded or whole tires in a reactor with no oxygen present. In the reactor the rubber is heated which softens the rubber polymers which aids in the breakdown into smaller molecules which allows them to be vaporized. Once a vapor, the smaller molecules are directed into a chamber where they are burned to produce an oil-based liquid which can be used as fuel.