An Experimental investigation on the pre-hea-ter cyclone reactors utilising in cement industry

AN EXPERIMENTAL INVESTIGATION ON THE PRE-HEA- TER CYCLONE REACTORS UTILISING IN CEMENT INDUSTRY SUMMARY Keywords: Cyclones, Pre-heater cyclones The most important part of cement production line is the rotary kiln. Before entering the rotary kiln, raw material, namely dust, should be heated to a certain temperature to reduce its heat load. To do this, multistage pre-heater type of cyclones have been widely used in cement industry to recovery heat energy of hot gas. The heat is, then, used in preheating of dust which is the raw material of the cement. Thus the dust is heated until its calcination temperature is reached. Therefore, a large amount of heat energy is saved. Nevertheless, the cyclones used as a pre-heater in cement processes have scarcely been investigated in view of heat transfer and fluid dynamics, up to now. In addition, most data in the field are not available in the open literature due to their commercial values. The variables which affect the cyclone performance are; hot gas flowrate, inlet/exit gas temperatures, gas density, pressure drop in the cyclone, geometrical specifications of the cyclone, raw material concentration and the velocity distribution of the gas flow. It is obvious that a study concerning pre-heater cyclone should be simultaneously elaborated with heat transfer and fluid dynamics principles. In this work, experiments were conducted to determine the effects of geometrical properties and operating conditions of the cyclone characteristics, on the pre-heater. A type of Humboldth cyclone with with one stage was used over the experiments. Test results have shown that the parameters mentioned above have a considerable impact on the pre-heater characteristics and must be consider in design considerations. However, for a general conclusion, more detailed studies should be conducted at various test conditions. XII