摘要 |
1. Method of heat treating fine-grain material, in particular cement raw material, using a multistage cyclone preheater through which the exhaust gases of a rotary tubular kiln pass, high-sulphur-content fuel being introduced into a precalcination zone disposed in the lowermost region of the cyclone preheater and the entire combustion air required in the precalcination zone being supplied by the rotary tubular kiln, characterised in that the kiln exhaust gases are dedusted before entry into the precalcination zone at exhaust gas temperature and at least a portion of the dust precipitating is discarded. |