Abstract:To address digestion of low grade and high sulfur bauxite in industrial application, effects of roasting temperature, roasting time and ore particle size on desulfurization by low-temperature roasting were investigated. The results show that sulfur removal rate of bauxite is 75.83% with sulfur content in ore of 0.29% under the optimum roasting desulfurization conditions including roasting temperature of 650 ℃, roasting time of 180 s, and ore particle size of 48 μm. Under the same digestion conditions, relative dissolution rate of alumina from roasted ore is 97.63%, which is 7.32 percent point higher than that of raw ore. Sulfur in bauxite mainly exists in form of pyrite, which is prior reaction with kaolinite to boehmite during roasting.