Analysis on the zero-g period and characteristic temperature of coal gangue during adiabatic oxidation process

Adiabatic oxidation processes of coal gangue under the different conditions of oxygen concentration and heating rate were analyzed by STA technology to investigate its specific zero-g period and characteristic temperature of every zero-g period.Based on the thermal analysis experimental results,the zero-g periods of coal gangue during adiabatic oxidation process under the different conditions is separated into four stages which are respectively the zero-g period of surface moisture,inherent moisture,volatile combustion and fixed carbon combustion.In the case of the same oxygen concentration which is 20%,the TG curves of adiabatic oxidation of coal gangue move to the high temperature zones along with the increasing of the heating rate,and the characteristic temperatures of every stage which are respectively the starting point,midpoint,inflection point and terminal point increases linearly when the heating rate increases,and the maximum burning rates of the zero-g periods of volatile combustion and fixed carbon combustion also increases when the heating rate increases,but the weight changes of every stage are basically the same.In the case of the same heating rate which is 10.0 ℃/min,the TG curves of adiabatic oxidation of coal gangue move to the low temperature zones along with the increasing of the oxygen concentration,and the characteristic temperatures which are respectively the starting point,midpoint,inflection point and terminal point and the weight changes of the zero-g periods of surface moisture and inherent moisture are basically the same along with the increasing of the oxygen concentration,but the characteristic temperatures which are respectively the starting point,midpoint,inflection point and terminal point of the zero-g periods of volatile combustion and fixed carbon combustion decreases linearly along with the increasing of oxygen concentration.