The invention relates to a flotation two-stage desiliconization method for high-
silicon bauxite, which is a flotation desiliconization technology for 
bauxite and belongs to the technical field of 
mineral processing engineering. The method comprises the following steps of: coarsely 
grinding the 
bauxite into particles with certain fine 
granularity; under the condition of a certain ore pulp concentration, performing flotation first-stage desiliconization by using 
sodium carbonate as a pH 
regulator and a dispersing agent of the ore pulp, water glass and 
sodium hexametaphosphate as a combined inhibitor of 
gangue mineral, 
lead acetate as an activating agent of the bauxite, 
sodium oleate as a collector of the bauxite and 
pine oil as a 
foaming agent, wherein the base flow in a flotation groove is a section of 
silicon-containing 
tailings; allowing foam products to enter a 
grinding machine and 
grinding the foam products into particles with fine 
granularity; adding the medicaments sequentially and mixing pulp; performing flotation second-stage desiliconization, wherein the base flow in the flotation groove is a section of 
silicon-containing 
tailings; and selecting the foaming products for multiple times to form bauxite concentrate. The sectional desiliconization method for 'flotation first-stage desiliconization after coarse grinding and flotation second-stage desiliconization after regrinding rough concentrate' is utilized, so the influence of ore argillization phenomenon on desiliconization is greatly reduced, the flotation desiliconization effect on the high-silicon bauxite is obvious, the 
silicon dioxide content of the bauxite concentrate can be reduced greatly, the ratio of aluminum to silicon of the bauxite concentrate is increased, and the 
recovery rate is high.