Task
Slightly angled downwards, the kilnʻs rotation transports the precalcined raw meal from the inlet to the discharge end (kiln hood), whereby the temperature increases along the kilnʻs length. Hereby, the required clinker phases are created at material temperatures up to 1450 °C.

Demands
For constructional as well as production-related reasons, the rotary kiln is subjected to a wide range of thermal, chemical, and mechanical influences.
Particularly the increasing use of alternative fuels leads to extremely high thermochemical and thermomechanical stresses in the refractory lining. Based on the material flow, a rotary kiln is usually divided into the following zones:
1. Kiln inlet cone
2. Preheating zone
3. Calcining zone
4. Upper transition zone
5. Clinkering zone
6. Lower transition zone
7. Discharge area.