Study on Thermodynamic Characteristics and Heat Transfer Method of Uncontrolled Fire in Coal Mine Gangue Mountain Spontaneous Combustion Based on System Dynamics

Table 3

Kinetic parameters of the second and third stages of coal gangue at a heating rate of 20°C/min.

Sample	Oxidation stage	Mechanism function	Activation energy (kJ·mol^−1)	Pre-exponential factor (log A/s^−1)	Relationship
2	II	Avrami−Erofeev	88.664	28.662	0.993
	III	Avrami−Erofeev	253.557	45.325	0.994
4	II	Reaction order	48.365	20.162	0.991
	III	Avrami−Erofeev	115.526	19.632	0.986
8	II	Avrami−Erofeev	105.345	36.23	0.988
	III	Avrami−Erofeev	354.594	66.335	0.998
12	II	Avrami−Erofeev	189.63	55.632	0.996
	III	Avrami−Erofeev	398.454	67.562	0.995