Influence of dolomite particle size on the kinetics of its thermal decomposition process

The results of an experimental study of the thermal decomposition of natural dolomite, carried out on laboratory equipment at constant temperatures of 650 °C, 700, 750, 800 and 850 °C, are discussed. Particles of Belarusian dolomite weighing 0.58 g, 0.88, 2.3, 2.7, 7.6 and 16.3 g were used as the test samples. An integral equation describing the kinetics of thermal decomposition of natural dolomites of Belarus is presented. It is shown that the reaction rate of thermal decomposition of dolomite depends not only on the temperature regime in the reaction zone, but is also largely determined by the mass of the samples under study. It has been established that the rate constant of thermal decomposition of dolomite in the studied range of sample masses can be determined by the empirical expression identified in the course of this study. The rate constants of thermal decomposition of dolomite particles of various masses have been determined. The values of the rate constants obtained empirically and those calculated taking into account the mass of the samples are compared. It is noted that the developed model is physically justified, and the dependence proposed in the work can be incorporated into existing engineering methods for calculating generator gas purification systems using dolomite as a catalyst and sorbent.

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