Fluorite beneficiation technology: from hand selection to efficient flotation

Fluorite, as an important non-metallic mineral resource, is highly valued for its wide application in chemical, metallurgical, building materials and other fields. Choosing a suitable beneficiation method is crucial to improving the grade and recovery rate of fluorite. At present, China's fluorite mines mainly use three methods: hand selection, gravity selection and flotation. Among them, flotation is widely used due to its high efficiency.

Hand selection is a traditional beneficiation method, suitable for ores with clear boundaries between fluorite and gangue and easy to identify with the naked eye. The advantages of this method are simple operation and low cost, but it also has problems such as high labor intensity and waste of resources.

The gravity selection method improves the grade of the ore by pre-discarding the tailings, creating favorable conditions for subsequent beneficiation operations. The heavy medium pre-selection process is an effective method in the gravity selection method. It has been applied in South Africa, Italy and other countries. This method can effectively remove impurities such as quartz and reduce the impact on subsequent grinding operations.

Floatation is the most critical link in fluorite beneficiation, especially when fluorite itself has good floatability. By controlling the pH value of the slurry within the range of 8-10 and using fatty acid anion collectors, effective separation of fluorite and gangue can be achieved. According to different types of associated gangue minerals, the fluorite flotation process needs to be adjusted accordingly:

Quartz-fluorite type ore: adopt a process flow of primary grinding and roughing, re-grinding of coarse concentrate, and multiple selections. Use Na2CO3 as a pH adjuster, and use water glass to inhibit silicate gangue minerals.

Sulfide ore-fluorite type ore: preferentially float sulfide ore, and then recover fluorite from the flotation tailings of sulfide ore. Since the activity of fluorite decreases during the flotation of sulfide ore, an activator needs to be added to improve its floatability.

Carbonate-fluorite type ore: The main carbonate gangue mineral is calcite, which is inhibited by organic and inorganic inhibitors such as lignin sulfonate, dextrin, etc.

Barite-fluorite type ore: adopt two processes of mixed flotation and preferred flotation, and achieve effective separation of fluorite and barite by selecting appropriate collectors and inhibitors.

In summary, the optimization of fluorite beneficiation technology needs to comprehensively consider factors such as ore type, composition and grade. Through technological innovation and process improvement, the beneficiation efficiency and product quality of fluorite can be improved to meet the market demand for high-quality fluorite.