In thermal recycling, the Old tires burned and converted into energy. Considering the magnitude of an uncontrolled tire fire, it is hard to imagine that the combustion of Old tires is an environmentally friendly method of disposal - but that is deceptive. Old tires are well suited as a fuel substitute in cement works, pulp works and power plants because they have a calorific value of approx. 9,0 kWh/kg and a sulfur content of approx. 1,2%.
The combustible elements of Old tires (Textile, rubber, soot, etc.) are used to generate energy, the non-combustible parts (ZnO, steel, etc.) oxidize completely and are used in cement production.
Thermal recycling represents the last step in the disposal hierarchy of used tires. Before a used tire is sent for thermal recycling, it can be passed through the Retreading get a second life.
A tire can no longer be retreaded or as tread tires are kept in the recycling cycle, material recycling is an environmentally friendly solution. Even if the tires cannot be recycled - this usually applies to silo tires, seal or silent tires - using them as a secondary raw material is a good alternative. Cement plants use old tires as a substitute fuel for thermal recycling. Modern European cement plants burn the tires under strict environmental regulations with low environmental impact.