Cement kilns are used for the pyroprocessing stage of manufacture
and other types of hydraulic cement, in which calcium carbonate
reacts with silica-bearing minerals to form a mixture of calcium
silicates. The cement kilns are the heart of this production
process: their capacity usually define the capacity of the cement
plant. As the main energy-consuming and greenhouse-gas–emitting
stage of cement manufacture, improvement of their efficiency has
been the central concern of cement manufacturing technology.
