Abstract: A low alumina silica bauxite ore in Guizhou Province has Al2O3 grade of 60.35%、SiO2 content of 13.53% and alumina silica ratio of 4.46.The aluminous minerals are mainly diaspore,and the siliceous minerals are mainly kaolinite,illite,chlorite.In order to determine the development and utilization process of the ore,the beneficiation test was carried out.The results show that the ore sample has been treated with one roughing and one scavenging under the condition that the fineness of the first stage grinding is -0.074 mm content 74.52%.When the regrinding fineness of the coarse concentrate is -0.053 mm accounting for 87.65%,it is treated by one roughing three cleaning two scavenging,and the middle ore returns to the closedcircuit positive flotation process in sequence for desilication,The bauxite concentrate with Al2O3 grade of 67.49%,alumina silica ratio of 8.81 and Al2O3 recovery of 78.04% is obtained.The desilication effect is significant,which provides a basis for the next stage of work.

Key words: Low alumina silica ratio, Bauxite, Flotation desilication, AC1