In recent years, with the development of industry, fluorite has become more and more widely used in chemical industry, metallurgy and other fields, its price has been rising, and its value has begun to approach scheelite, and 43% of my country’s fluorite reserves are associated minerals.
The resource utilization rate needs to be improved, so the comprehensive utilization of fluorite is of great significance. So how can scheelite and fluorite ore be recovered smoothly?
I. The beneficiation method of scheelite
The floatability of scheelite is good, and it is often treated by the combined method of gravity separation and flotation.
Scheelite flotation separation mainly solves the problem of separation from sulfide ores and non-metallic ores, specifically:
- Separation of scheelite from sulfide ore. Xanthate is used to capture sulfide minerals prior to flotation of scheelite. When floating scheelite, add a small amount of oxide and sodium sulfide to suppress a small amount of sulfide that has not been floated.
- Separation of scheelite from calcite and fluorite. Commonly used thick slurry high temperature method. First concentrate the pulp to a concentration of 60~70%, then add water glass, heat the pulp to above 80°C, stir for 30-60 minutes, then dilute with water, and flotate scheelite at room temperature. The product in the tank is Fluorite and calcite.
- Separation of scheelite from quartz-like silicates. Using oleic acid as a collector and water glass as an inhibitor, can inhibit quartz and silicate gangue and float scheelite.
- Separation of scheelite and barite. Because water glass has similar inhibitory effects on scheelite and barite, it is difficult to separate water glass alone, and it is necessary to use alkyl sulfate or sulfonate as collector to reverse flotation barite under the condition of PH=1.5-3.0, scheelite is obtained in the tank.
- Tungsten and tin separation. Electric selection and flotation can also be used. During flotation separation, scheelite is collected with fatty acid, and cassiterite is suppressed with water glass. Tungsten and molybdenum separation. Molybdenum is floated first, then scheelite is floated with oleic acid, and a large amount of water glass is used to heat and select the scheelite.
Commonly used collectors for scheelite are oleic acid, oleic acid soap and 731 oxide paraffin soap. There was once a beneficiation plant that used high-temperature beneficiation to select scheelite. The production technical indicators: the grade of scheelite concentrate was 67.03%, the tailings was 0.095%, and the recovery rate was 80.17%.
II. The beneficiation method and beneficiation equipment of fluorite ore
Fluorite is mainly composed of calcium fluoride, which is an important metallurgical flux and chemical raw material. As a mineral resource, what is the beneficiation method and beneficiation equipment of fluorite ore?
Fluorite ore beneficiation mainly adopts flotation method and gravity separation method. Flotation method is used to deal with fine-grained dissemination and low-grade fluorite ore. Flotation method is also one of the most important beneficiation methods for fluorite ore beneficiation. The only way to get fluorite ore powder. Gravity separation is used to process the beneficiation and purification of coarse-grained embedded high-grade fluorite ore to obtain coarse-grained metallurgical grade fluorite lump ore, which is the main method for producing fluorite concentrate for steelmaking industry.
- Flotation method: High-quality fluorite concentrate powder can be obtained by flotation treatment of fluorite ore, but the investment of flotation equipment is large, the operating cost is high, and it has certain pollution to the environment. Therefore, under the premise that environmental protection requirements are becoming more and more strict today, the application of fluorite ore flotation is more and more limited, which also promotes the improvement and application of fluorite ore gravity separation technology and equipment to some extent.
- Gravity separation has a very good effect on the purification of coarse-grained embedded fluorite ore. Under normal circumstances, gravity separation can also be used for beneficiation and purification of fine-grained fluorite ore, which has the advantages of energy saving, high efficiency and environmental protection. In the new type of fluorite beneficiation plant, the application of gravity separation method has gradually surpassed the flotation method.
B. Mineral processing method
- Gravity separation method: The gravity separation method is suitable for the treatment of coarse-grained and high-quality fluorite lump ore, and also has a good effect on the beneficiation of some fine-grained fluorite ore. There are fluorite ore gravity separation plants in Xinyang, Henan, Zhenglanqi, Inner Mongolia, Jinchang, Gansu, and Wuchuan, Guizhou.
- Flotation method: The flotation method is suitable for the beneficiation of fine-grained disseminated low-grade fluorite ore, and its concentrate is mainly used for the production of hydrofluoric acid in the chemical industry. The number of selected equipment in the stone flotation equipment increases, and the equipment investment increases. The flotation method has certain pollution to the environment, and many regions have banned the use of the flotation method to select fluorite.
C. Gravity beneficiation equipment
The gravity separation method is mainly used for the beneficiation and purification of coarse-grained embedded fluorite ore. Therefore, the gravity separation equipment of fluorite ore is mostly jig concentrator. The beneficiation and purification of fluorite ore have good results and ideal processing capacity, and various beneficiation indicators have reached a satisfactory level. The application of fluorite gravity separation jig is also more and more extensive.
The beneficiation of scheelite is based on the dissemination characteristics of the ore, and the combination of gravity separation and flotation is often used. Adding polyvalent metal salts to water glass can significantly improve the flotation effect of scheelite. The content of metal sulfide in fluorite ore is relatively high, and sometimes the content of lead and zinc can reach industrial grade. Therefore, when developing and utilizing, we must also consider the recovery of metal ore.