Abstract:
Combustion experiments of Changzhi coal at 550-1 000℃ were conducted in a tube furnace reactor in air and O
2/CO
2, respectively. The XRF, XRD etc. were employed to study the characteristics of raw coal and its demineralized coal. Effects of mineral matter in coal on combustion characteristics and release of SO
2 and NO
x during combustion were investigated using TG-DTG and Antaris-IGS. The results show that ignition and burnout temperature of the demineralized coal are lower than those of raw coal. In O
2/CO
2 the ignition and burnout temperature of raw coal and the demineralized coal are all higher. This shows that when oxygen concentration is 20%, the coals are easier to ignite and burnout in air. Besides that, SO
2 emission of the demineralized coal is higher than that of raw coal; while NO
x emission is opposite. For raw coal, SO
2 emission is higher when combusted in O
2/CO
2; while for the demineralized coal, it is opposite. During combustion in O
2/CO
2, NO
x emission is always lower whether for the raw or the demineralized coal.