STUDIES ON HYDRO = PRETREATMENT OF BAUXITE

To increase the ratio of A/S hydro-pretreatment of bauxite from Shanxi was studied. The results indicated that the value of ak should be either small(3.0) or great (176) for the hydro-pretreatment of bauxite at a certain temperature (95℃) and L/S. The value of A/S of refined bauxite was all bigger than 9.5, which fit the alumina production by Bayer. There was obvious effect of temperature and L/S on the value of A/S of refined bauxite, ratio of desiccation and stability of solution after. bauxite was pretreated. It also showed that there was not obvious difference of structure between original bauxite and refined bauxite after pretreatment and the refined bauxite could be digested by the current technology of Bayer in China.