Slag vertical roller mill can be used to grind non-inflammable and non-explosive materials with Moh's hardness below 9.3 and moisture content below 6%, Such as: slag, limestone, calcite, barite,dolomite, potassium feldspar, marble, talcum, gypsum, kaolin, bentonite, medical stone, rock phosphate,iron ore, quartz, active carbon, coal, ect.