Experimental study on low temperature oxidation of gas coal with different water content

In order to study the spontaneous combustion characteristics of gas coal with different water content, low-temperature oxidation experiments were carried out on five kinds of coal samples respectively through the programmed temperature experiment system. The test results show that in the process of low temperature oxidation, the spontaneous combustion characteristics of gas coal with different water content change exponentially with the increase of temperature. The volume fraction of CO and CO₂, oxygen consumption rate and exothermic intensity of coal samples are higher than raw coal at low water content and lower than raw coal at high water content. In the accelerated oxidation stage, the activation energy of raw coal is 75.7 kJ/mol, while the activation energy of coal sample with water content of 5.87%, 9.81% and 13.81% is decreased by 6.8 kJ/mol, 25.6 kJ/mol and 4.6 kJ/mol, respectively. Meanwhile, the activation energy of coal sample with water content of 17.85% is increased by 4.1 kJ/mol. The results show that within a certain range, the higher the moisture content, the lower the apparent activation energy and the higher the spontaneous combustion tendency of coal. However, excessive moisture will inhibit the accumulation of heat, and the activation energy of coal will increase and the spontaneous combustion tendency will decrease.