Oxidation characteristics of coal by STA-FTIR experiment

The aim of this study was to use the simultaneous thermal analysis-Fourier transform infrared spectroscopy (STA-FTIR) technique to analyse the oxidation and exothermic behaviours for four types of fresh coals based on vari- ous critical factors,such as characteristic temperatures,change of heat,releasing gases,reaction kinetics. A foundation of prevention and control technology in spontaneous combustion of coal was established. In accordance with experimen- tal results,with the decrease of metamorphic grade of coal,the volatile matters,heat releasing rate,and the total heat release were also increased. The characteristic temperature gradually reduced,and the initial temperature and peak temperature in gases releasing of H2 O,CO2 ,CO,and CH4 during the non-isothermal oxidation process were lower,de- creasing in the generation of CO. By contrary,the great amounts of CO2 and H2 O were increased. In addition,the func- tion of reaction mechanism in water evaporation,oxygen desorption,and mass gain process are similar. This demon- strates that the different coals have a similar reaction process. When the metamorphic grade of coal is lower,the oxidation and combustion reaction is easier and the hazard of spontaneous combustion of coal is more serious. Therefore,ac- cording to different storage,mining,or transportation conditions,the cooling system,sealing off the cracks,or suitable inhibition agent should be adopted to prevent the spontaneous combustion in the lower metamorphic grade of coal with low initial temperature.