Roasting Pretreatment and Digestion Performance of High Sulfur Bauxite

Roasting pretreatment of high sulfur bauxite was studied using a fluidized bed. The effects of roasting temperature,roasting time and particle size on roasting desulfurization performance were studied by orthogonal experiments. The experimental results indicated that the sulfur in bauxite was successfully discharged as gas form through roasting. Among the parameters in tested ranges,the optimal roasting parameters were 850℃ roasting temperature for 40 min holding time,and the optimal ore particle size was 165 μm. Digestion rate of roasted ore was also tested. Compared with the digestion conditions of head ore,the reasonable digestion temperature was reduced to 220℃ and molecular ratio reduced to 1.4.