EXPERIMENTHAL STUDY OF CALCIUM OXIDE CARBONATION KINETICS UNDER ISOTHERMAL CONDITIONS
Abstract
The results of experimental studies of kinetics of the reaction CaO + CO2 = CaСО2 performed at isothermal conditions at temperatures of 773, 873, 973 and 1123 K are being discussed. Pyrolysis gas, containing approximately 14.5% vol. of CO2 was fed during the experiments into the reaction zone, which housed the sample of calcinated dolomite. The extent of the reaction was determined from the weight gain of the sample kept at a constant temperature. Analysis of the data has shown that the kinetics of the CaO carbonation reaction is characterized by typical periods of heterogeneous processes, such as periods of induction, reaction acceleration and deceleration. The rate-determining step of the overall process for small degrees of conversion is a chemical reaction of CaO and CO2 . Activation energy and pre-exponential factor of the Arrhenius equation were estimated for this stage on the basis of the performed study. They are 29.6 kJ / mol and 0.36·10–1 min-1 (6.0·10–3 s-1 ) respectively.
About the Authors
M. V. Malko
Institute of Power Engineering of the National Academy of Sciences of Belarus
Belarus
Belarus
S. V. Vasilevich
Institute of Power Engineering of the National Academy of Sciences of Belarus
Belarus
Belarus
U. M. Bahach
Institute of Power Engineering of the National Academy of Sciences of Belarus
Belarus
Belarus
D. V. Degterov
Institute of Power Engineering of the National Academy of Sciences of Belarus
Belarus
Belarus
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