This type of ore finely dispersed, it is possible to obtain by conventional flotation bauxite ore high silica aluminum (6 to 8.9); however, fine mineral rate is only 20% to 30%. The low yield of bauxite concentrate is due to the high content of less than 5μm in the ore-grown pulp. The yield of different types of bauxite is less than 5μm and the yield is 50%-80%. Like other ore flotation, the low floatability of fine-grain bauxite is due to the increased surface area of ​​the particles, the low rate of basic flotation, and other factors.

Selective flocculation of fine-grained minerals in advance is one of the most promising methods for improving flotation efficiency. Whether it is to study collectors with high-efficiency flocculation, or to search for selective polymeric flocculants, selective flocculation can be achieved. When the amount of minerals to be separated in the treatment of bauxite suspension is high, selective flocculation should be rationally applied as an independent mineral processing operation. The selective flocculation process includes: (1) dispersing and stabilizing the slurry by physical-chemical methods; (2) selectively flocculating the slurry with the polymer; (3) classifying the material according to a certain particle size to obtain flocculated sediment and overflow. The product overflows as a slurry fraction in a dispersed state.

A kaolinite-monohydrate soft bauxite bauxite is treated by a coarse mechanical mechanical disintegration-fine particle selective flocculation process, as shown in Figure 1a. The results of the selection are shown in Table 1. It can be seen from the table that the ore contains 53.3% Al ₂ O ₃ and 17.5% SiO ₂ . The bauxite concentrate contains Al ₂ O ₃ 62.4%, SiO ₂ 10.2%, and aluminum recovery rate of 58.1. %, the ratio of aluminum to silicon increased from 3.1 to 6.2, and a certain sorting effect was obtained.

Table 1 A kaolinite-monohydrate boehmite ore selection index

Figure 1 Flow chart of the selection process of boehmite bauxite

A-a certain kaolinite; b-a certain chlorite