Cement clinker prodn. on sinter bed

Cement clinker is produced by (a) dry grinding raw cement components to prepare raw meal; (b) mixing the raw meal with solid fuel; (c) pelletising the mixt. with concurrent addn. of calcium chloride CaCl2; (d) drying the pellets in a heated drying zone in a dense layer; (e) roasting the layer of pellets by burning a solid fuel over the surface of the layer and holding the temp. of the resultant gaseous prod. at 1150-1250 deg.C for no longer than half the roasting period and drawing fuel combustion gaseous prods. through the pellet layer and removing exhaust gases; (f) lowering the temp. to 900-1000 deg.C to effect dechlorination, gradually in the direction of the cooling zone; and (g) cooling the cement clinker to ambient temp. The process combines the advantages of improving the clinkering process by lowering the temp. of the final clinkering with the acid of calcoum chlorode, currently only used in rotary kilns, with the advantages of roasting by burning a fuel over a layer of pelletised material on a sinter bed and drawing hot gases through the bed.