Background of used old tyres

There are over one billion end-of-life tires generated annually, worldwide, and it is estimated that four billion unwanted end-of-life tires exist in landfills and stockpiles. Around 246 million scrap tires were generated in the U.S. in 2015. As a result, the importance of tire recycling cannot be understated. Going back 100 years or so into the history of tires, tire recycling was a priority, with the price of an ounce of rubber rivaling the price of an ounce of silver. Such economic incentives faded, however.

The introduction of synthetic rubber made from cheap imported oil, as well as by the adoption of steel belted radial tires made tires cheaper (less urgent to recycle) as well as more difficult to recycle. As a result, worn out tires increasingly found their way to landfills or were often dumped illegally. Fortunately, tires are now increasing diverted from landfills.
 

The Urgency of Diversion
 

Tires sent to landfills or dumped illegally are a significant concern. Old tires provide shelter for rodents, and can trap water, providing a breeding ground for mosquitoes. In landfills, tires consume up to 75 percent air space, In addition, tires may become buoyant and rise to the surface if they trap methane gases. This action can rupture landfill liners that are designed to prevent contaminants from polluting surface and ground water. Approximately 700 to 800 million old tires were estimated to be illegally stockpiled in 1994, with that total reduced to approximately 275 million by 2004.