Fluorite is commercially named fluorspar composed of calcium fluoride (CaF2). It is the principal source of fluorine. The same is used in the production of hydrofluoric acid, which is used in a wide variety of industrial applications including glass etching. Fluorite tends to occur in well-formed isometric crystals, forming cubes and octahedrons. It also occurs in both massive and earthy forms, and as crusts or globular aggregates with a radial fibrous texture.
1 Grinding size (i.e. grinding fineness)
In the beneficiation operation, the grinding fineness is one of the most important factors affecting the beneficiation index, which directly affects the beneficiation output of the final concentrate. Usually, the flotation of fluorite ore concentrate varies regularly with the coarse and fine flotation size in a certain size range.
When the particle size is coarse, the recovery rate of fluorite is high but the grade is low; when the particle size is fine, the recovery rate of fluorite is low but the grade is high. Therefore, in order to improve the fluorite recovery, the grinding size should be reduced, and vice versa.
2 Pulp temperature
Fluorite is usually flotation with the carboxylic acid trap. Because of the high freezing point of carboxylic acid, the pulp temperature has a significant influence on the flotation process.
It is tested that when In a certain temperature range, the higher temperature is, the solubility of carboxylic acid in the pulp increases, so it is easy to disperse, the trapping ability of fluorite ore is strong, and the recovery rate is high. The grade is high, but the recovery rate is a bit low.
3 Trapping agent
Under certain conditions, when the amount of trapping agent is larger, the recovery is high, but the grade is low. In general, the amount of catcher is increased in roughing to increase the recovery rate as much as possible; when the amount of catcher is small, the recovery rate is low, but the grade is high. In the selection operation, generally choose to add less or no trapping agent to improve the concentrate grade.
The main function of the inhibitor is to inhibit the vein minerals and harmful elements in the ore. In Xinjiang fluorite ore inhibitor test, when the inhibitor dosage is low, the concentrate product in the vein minerals calcite, barite content, resulting in a lower grade of the concentrate product, but due to a section of grinding operations, fluorite and vein minerals dissociation is not complete, so that part of the fluorite and vein minerals adhered together with the fluorite is selected, resulting in a higher recovery. When the amount of inhibitor is large, the grade is high, but the recovery rate is low. In the selection operation, generally take to add inhibitor to improve the grade of the concentrate.
5 Pulp level
In the flotation process, the fluorite minerals with better floatability will reach the top of the froth layer first.
6 Pulp pH
The pH of the pulp has a great influence on the flotation of fluorite. When oleic acid is used as the trapping agent, the flotation is better when the pH is 8-11; when the pH is 6, the flotation is also better. For different types of fluorite ore, the floatability of its vein minerals is also influenced by the pH value, which in turn affects the sorting effect, for example, when oleic acid is used as the trapping agent, the floatability of fluorite and calcite is better at pH 8-9.5.
7 Quality of water
When fluorite is trapped by oleic acid, Ca2+ and Mg2+ ions are present in the water. Some studies have shown that the presence of Mg2+ can seriously interfere with the flotation of fluorite and significantly reduce the flotation effect, so the water used for flotation of fluorite needs to be softened in advance.
8 Part of the middle ore concentration re-election return
It is known from experimental research that when the middle ore is returned sequentially, some of the vein minerals keep circulating in the flotation system and cannot be thrown away, which affects the flotation index; if part of the middle ore with high vein mineral content is selected for concentrated re-election, the re-elected concentrate is returned to the roughing and the tailing is thrown away directly, this return method not only reduces the load of the circulating system, but also improves the grade and recovery of the concentrate product.
9 Mechanical stirring intensity
Within a certain range of stirring intensity, with the increase of stirring intensity, the contact time between the chemical molecules and mineral particles can be accelerated, reducing the flotation time, thus improving the recovery rate and grade of the concentrate.
10 Operating conditions
In the actual production process on site, the production conditions are unstable due to improper management or negligence of the operating workers, which can also affect the final fluorite concentrate beneficiation index.