Experimental study and chemical equilibrium calculation on the mineral transformation of high-alkali coal under oxy-fuel condition

[Display omitted] •Plasma ashing method was used to determine the minerals in raw high-alkali coal.•Effects of high SO2 and H2O concentrations on mineral transformation were studied.•The simulation based on the plasma ash was performed under oxy-fuel condition.•The mineral transformation under O2/CO2 and O2/RFG conditions were summarized. The study aimed to study the mineral transformation of high-alkali coal to address the ash-related issues in oxy-fuel combustion. However, the traditional ashing method alone is inappropriate to study the mineral transformation at the initial stage of coal combustion due to the high ashing temperature. Hence, both the plasma ashing method (