Fluorite has good buoyancy, and fatty acids are often used as collectors. The pH value of the pulp has a great influence on the flotation effect of fluorite. Using oleic acid as a collector, when the pH of the pulp is 8-11, the floatability of fluorite is better. Secondly, increasing the temperature of the pulp can also improve the flotation index of fluorite. At the same time, the flotation behavior of fluorite with different particle sizes is also different.

Coarse-grained fluorspar flotation is characterized by strong selectivity; therefore, its concentrate grade is high, but the recovery rate is low; medium-grained fluorspar flotation results in high concentrate grade and recovery rate; fine-grained fluorspar flotation The selected concentrate grade and recovery rate are both low. When oleic acid is used as a collector for flotation of fluorite, there is also a higher requirement for water used for flotation. That is, when the water quality is hard water, the water entering the flotation process must first be softened in advance.

Fluorite Flotation Method

The main problem of fluorite flotation is the separation from paragenetic gangue (such as quartz, calcite, barite, etc.). There is also the problem of separation from certain sulfides. Depending on the situation, the following methods can be used:

(1) Fluorite ore containing sulfide ore

Generally, xanthate collectors are used to float sulfide ore, and then fatty acid reagents are added to float fluorite. Sometimes in fluorite flotation operations, a small amount of sulfide ore inhibitors (such as cyanide) are added to suppress residual sulfide to ensure the quality of fluorite concentrate.

(2) Separation of fluorite, barite and calcite

Generally, oleic acid is used as a collector to float out fluorite. When using oleic acid to float fluorite, a small amount of aluminum salt is added to activate fluorite, and dextrin is added to suppress barite and calcite.

For complex fluorite mines containing more calcite, limestone, dolomite, etc., it is better to use tannin extract and lignosulfonate to inhibit these gangue minerals.

(3) Separation of fluorite and quartz

Use fatty acid as collector to float fluorite, water glass as inhibitor of quartz, and sodium carbonate to adjust the pH value of the slurry to 8-9. The amount of water glass should be well controlled. A small amount can activate fluorite, but the inhibitory effect on quartz is not enough, and fluorite will also be inhibited when it is excessive.

In order to minimize the amount of added water glass and achieve the inhibitory strength of quartz gangue, polyvalent metal ions (such as Al3+, Fe3+), alum, aluminum sulfate, etc. are often added at the same time as water glass is added. In addition, the addition of Cr3+ and Zn2+ ions is also effective, and these ions not only inhibit quartz, but also calcite.

(4) Separation of fluorite and barite

Generally, fluorite and barite are mixed and floated first, and then separated. In mixed flotation, oleic acid is used as collector and water glass is used as inhibitor. Generally, the following methods can be used for the separation of mixed concentrate:

1) Inhibit barite with dextrin or tannin and iron salt, and float fluorite with oleic acid;

2) Flotate barite with hydrocarbyl sulfate, and what is left in the flotation tank is fluorite concentrate.