Coal oxidation; Threshold temperature; Activation energy; Calorimetry

Character of the temperature dynamics of coal oxidation rate was investigated at temperatures from ambient to 160°C for five bituminous coals. Non-linear development of the Arrhenius plots (Ln (oxidation rate) versus Reciprocal temperature) was found with breaks at temperatures between 45°C and 100°C. The break was denoted as threshold temperature Tth and its value indicates a temperature beyond which the coal oxidation gains more intense character. Also, the influences of the coal grain size, coal moisture content and oxygen concentration on temperature dynamics were examined and analysed from the point of view of the threshold temperature and activation energy of the coal oxidation.

Character of the temperature dynamics of coal oxidation rate was investigated at temperatures from ambient to 160°C for five bituminous coals. Non-linear development of the Arrhenius plots (Ln (oxidation rate) versus Reciprocal temperature) was found with breaks at temperatures between 45°C and 100°C. The break was denoted as threshold temperature Tth and its value indicates a temperature beyond which the coal oxidation gains more intense character. Also, the influences of the coal grain size, coal moisture content and oxygen concentration on temperature dynamics were examined and analysed from the point of view of the threshold temperature and activation energy of the coal oxidation.