Temperature rising rates and oxygen concentrations influerced to apparent activation energy of coal

In order to study the effect of temperature rising rate and the oxygen concentration to apparent activation energy, simultaneous thermal analyzer was applie d to thermal gravity experiment of coal samples from Changzhi Changcun Mine. Under different temperature rising rates and oxygen concentrations,feature point temperatu re T1- -T5of coal and oxygen reaction features was found and Coats- Redfern integral formula was applied to analyse and calculation on experiment results and apparent a ctivation energy of coal under relevant conditions was obtained. The results showed that within certain scope,due to temperature rising rate of the coal sample increased,re action rate would be increased and coal and oxygen reaction would be easily conducted. When temperature rising rates were 2,5,10,20 and 30。C /min,apparent activation energy of coal would be 160. 734 6,159. 437 6,141. 870 1,117. 659 7 and 95. 261 8kJ 1 mol individually. The apparent activation energy of coal would be reduced with incr eased temperature rising rate and variation law basically would be subjected to index function. In addition,due to oxygen concentration increased,coal molecules would req uire more activated active groups to reacted with oxygen molecules. To activate those active groups would require more energy. When oxygen volume fractions were 5%,1 0%, 15%,21% and 30% individually,apparent activation energy of coal would be 85. 825 4,111. 956 3,127. 021 3,141. 870 1 and 155. 571 6 k J /mol individually. With oxyge n concentration increased,the apparent activation energy of coal would be increased and the variation law would be subjected to logarithm function.