Kinetics of thermal decomposition of limestone particles in a fluidized bed reactor

The decomposition of limestone particles in fluidized bed reactor was studied over the temperature range of 1034-1173K and over a particle size range from 0.25 to 1.85 mm. These conditions are typical for fluidized bed combustors. The decomposition was carried out at different CO 2 concentrations (between 0 and 15%) The results show that the rate of decomposition of limestone particles of this size is controlled by chemical reaction. The activation energy found for the decomposition reaction was 42200 cal/mol. The calcination times measured were shorter than those predicted by the model in the case of the chemical reaction control and spherical unreacted core. This fact indicates that decomposition interface is greater than those defined by the surface of a sphere. The estimated values of initial CaCO 3 -CaO interface are between three and five times the external surface area of a sphere. This parameter appears to be dependent on particle size and independent of calcination temperature. The use of the parameter in the decomposition model predicts satisfactory all experimental results