Spontaneous combustion of sulfide ores is one of the more severe safety problems in metal mines. Three representative sulfide ore samples (denoted as 1-2, 2-2, and LB4) were obtained from a typical metal mine in China. The chemical reaction processes were analyzed by thermo-gravimetric analysis (TG) and differential scanning calorimetry analysis (DSC) at the heating rates of 5, 10, and 15°C/min in air flow from ambient temperature to 800 °C. The corresponding curves of TG and DSC for each sample under different conditions were gained, and their combustion characteristic parameters were also presented. Based on the Flynn-Wall-Ozawa method, the reaction activation energy for 1-2, 2-2, and LB4 samples was calculated, which is 427.242, 116.835, and 56.225kJ·mol~(-1) respectively. It can be concluded that LB4 sample is the most susceptible one to cause spontaneous combustion for its lowest activation energy value, whereas 1-2 sample is difficult to arouse spontaneous combustion. This explana- tion is in accordance with the factual situation in mines. Therefore, activation energy value can be used as the standard for evaluating spontaneous combustion tendency of sulfide ores.
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