Energy generation through the use of tires
In thermal recycling, used tires are incinerated under controlled conditions and used to generate energy. Industrial thermal recycling is a technically sophisticated and strictly regulated process. Under defined conditions, used tires make a significant contribution to energy production when incinerated.
Used tires are very well suited as alternative fuel due to their high calorific value of approximately 9,0 kWh per kilogram and their relatively constant sulfur content of around 1,2 percent. They are used particularly in cement plants, pulp mills, and power plants, replacing fossil fuels such as coal or oil. All combustible components contained in the tire, such as rubber, textiles, and carbon black, are used for energy generation.
The non-combustible components of used tires, including steel and mineral components such as zinc oxide, oxidize completely during the combustion process. In cement plants, these residues are directly integrated into the production process and used as a raw material component in the cement clinker. This eliminates additional waste, and the material components are put to good use.
Within the waste disposal hierarchy, thermal recycling represents the final stage of recycling for used tires. Before a tire is sent for this type of recycling, it should remain in use for as long as possible, for example through retreading or use as a treaded tire. If this is no longer possible, mechanical recycling often represents an environmentally sound alternative.
For certain tire types, such as silo tires, sealed tires, or silent tires, mechanical recycling is often not feasible. In these cases, thermal recycling offers a viable solution. Modern European cement plants use used tires as a secondary fuel under strict environmental regulations, ensuring low-emission and controlled combustion.