1. Rotary kiln and kiln shop

With the exception of vertical straight furnaces, now obsolete but still in service in the Far East (China, the world's leading producer, achieves 2/3 of its production with straight furnaces) and experimental furnaces under development (fluidized bed in Japan), all furnaces are now of the "rotary furnace" type.

The evolution of clinkerization process technology has led to a reduction in the relative importance of the rotary kiln within the kiln shop. The five essential operations to be carried out in the kiln shop are (figure 1 ):

• drying,

• preheating up to 500 C,

• decarbonation from 700 to 1,050 C,

• clinkerization...