Abstract:Digestion performance of high sulfur bauxite was investigated by orthogonal experiment. Regression equation of dissolution rate of alumina and sulfur was obtained. Dissolution process of high sulfur bauxite was optimized with single factor experiment. The results show that temperature is the key factor affecting dissolution performance. Dissolution rate of sulfur is obviously improved when temperature is below 260 ℃. Dissolution rate of alumina drops with increase of alkali concentration, while digestion time and lime dosage have no obvious effect on dissolution performance. The relative dissolution rate of alumina is 95% and dissolution rate of sulfur is below 26%, which are in high accordance to regression equation, under the optimum process parameters of “high temperature and low alkaline” including digestion temperature of 250 ℃, Nk=255 g/L, digestion time of 70 min, and lime dosage of 6%. The process is suitable for processing bauxite with sulfur content of 1.47% below.