Graphite is an allotrope of carbon, which can be divided into block graphite, scale graphite and cryptocrystalline graphite. The crystallization degree and scale size determine the process method of graphite beneficiation. Block graphite industrial value is not high, so it is not used. Although scaly graphite and cryptocrystalline graphite have high industrial value, mineral dressing is more difficult.
In this paper, fine scale graphite and cryptocrystalline graphite are selected as representatives to discuss the difference in graphite ore beneficiation process from four aspects of grinding method, grinding concentration, medium ore return mode and pharmaceutical dosage.
The fine scale graphite because of the extremely fine grain size, the grinding strength of the grinding section is larger for the fine scale graphite, and the ore can be directly ground to the fine fineness. The subsequent regrinding mainly only plays the role of cleaning the flotation concentrate. When the fine scale graphite is regrinding for a period, the grinding fineness can directly reach the standard, and the subsequent regrinding operation almost no longer has an impact on the grinding fineness.
With the increase of the number of regrinding sections of cryptocrystalline graphite ore, the fineness of grinding ore gradually decreases. Although the particle size of cryptocrystalline graphite is also very fine, the ore will pass the fine grinding. Therefore, it is recommended to grind the hidden crystalline graphite gradually in the grinding process.
The grinding concentration of fine scale graphite and cryptocrystalline graphite depends on the fixed carbon content in graphite. If the graphite has low fixed carbon content, the grinding concentration is low, the concentrate rate is low, and vice versa. Therefore, in order to improve the grinding efficiency, the fine scale graphite can concentrate the selected foam products before regrinding to improve the grinding concentration and crude concentrate mineral rate.
The hardness of cryptocrystalline graphite ore is large. In order to save the grinding time, the ball mill with higher grinding efficiency and higher grinding concentration can be selected to improve the recovery rate.
Because it is easy to separate graphite and gangue mineral in fine scale graphite, it can be effectively sorted after its return. However, the buoyability of cryptocrystalline graphite is worse than that of fine scale graphite, graphite is not easily separated from gangue minerals, and the return of middle ore is not conducive to separation, and may even worsen the flotation index.
Therefore, it is suggested that the treatment of fine scale graphite is to return the medium ore separately. The middle ore of cryptocrystalline graphite are treated separately to recover fixed carbon more effectively.
Generally speaking, the overall amount of fine scale graphite and cryptocrystalline graphite ore is large, which is related to the thickness of graphite embedded grain. In fine scales, graphite is scaly, and graphite in cryptocrystalline graphite is cryptotic. The natural buoyability of scale graphite is better than that of cryptocrystalline graphite. Therefore, in order to achieve the same flotation effect, the dosage of cryptocrystalline graphite is significantly higher than that of fine scale graphite.
For fine scale graphite, the increase of the fixed carbon content of crude concentrate before the capture amount reaches the critical point. The change of the amount of foaming agent has less influence on the fixed carbon content of crude concentrate.
For cryptocrystalline graphite, the excessive increase in the amount of collector and foaming agent will lead to the decrease of the fixed carbon content of coarse concentrate. Therefore, the amount of the agent should be appropriately selected according to the specific situation of the graphite ore.
The above is the difference in the mineral processing process between fine scale graphite and cryptocrystalline graphite in four aspects. It is suggested that the mine owner should consult the professional concentrator before the establishment of the concentrator, and conduct the beneficiation test to determine the nature of the graphite ore, and customize the professional beneficiation plan to achieve the ideal return on investment.
