The mineralogy of Zhundong coal and its combustion-generated particles were characterized in detail by computer controlled scanning electron microscopy (CCSEM). The experiment was done on a lab-scale drop tube furnace. The results showed that there were calcite

kaolinite

pyrite

pyrrhotite

oxidized pyrrhotite and unclassified minerals in Zhundong coal. The mass fraction of quartz

iron oxide and dolimite increased sharply

while the mass fraction of calcite and unclassified minerals decreased. Also

the behaviors of Na

Fe and Ca as the important elements to the ash deposition

and their particle size distributions were investigated.