Tire derived fuel (TDF) is a fuel derived from waste tires of all kinds. TDF is a major use for scrap or waste tires is fuel. This may include whole tire or tires processed into uniform, flowable pieces that satisfy the specifications of the end-user. Waste tires are used as fuel either shredded or whole depending on the type of combustion unit.
Tire Derived Fuel (TDF) Markets
TDF is the oldest and most developed market for waste tires in the U.S. Industrial facilities across the country, including cement kilns, pulp and paper mills and electric utilities use TDF as a supplemental fuel to increase boiler efficiency, decrease air emissions and lower costs. More than 52 percent of the 300 million waste tires generated annually are consumed as TDF in these facilities providing a cleaner and more economical alternative to traditional fuels.
Combusting Tires fuel is Excellent and Environmentally Sound Method
The U.S. Environmental Protection Agency (EPA) described TDF as a high Btu-value fuel with lower emissions, including lower greenhouse gas emissions, than comparable traditional fuels, in a 2009 Advanced Notice of Proposed Rulemaking. In earlier studies, EPA concluded, “With proper emission controls, burning tires for their fuel energy can be an environmentally sound method of disposing a difficult waste.”
Waste tires make an excellent fuel because of their high heat value. Each tire has energy potential. The heating value of an average size passenger tire is between 13,000 and 15,000 Btu/lb., which compares with about 10,000 to 12,000Btu/lb. for coal. The primary reason for using tire fuels is to save fuel costs. Further, they are compact, have a consistent composition and low moisture content-all benefits to the fuel user. Another major reason for combusting tires as fuel is to decrease the number of waste tires disposed in landfills or stockpiles.
Nationally waste tires represent a potential energy source of 1.01 quadrillion Btu per year based on a discard rate of 300 million tires per year each weighing an average 22.5 lbs with 15,000 Btu per pound. This is equivalent to 17 million barrels of crude oil and represents about 0.24 percent of the U.S. energy needs. Given this energy value, it is clear that waste tires compete with comparable traditional fuels including coal, petroleum coke and wood wastes.