Impurities in brown corundum - white spots

White spots refer to the white impurities appearing in the grain size of brown corundum, which are formed during the smelting process of brown corundum. Raw materials such as iron filings and anthracite added in the bauxite ore and smelting process themselves will contain various impurities, and then chemical reactions will occur during the high-temperature smelting process of the electric arc furnace and some impurities will also be generated. Among them, the white dots are most visible to the naked eye. These impurities will affect the effective ingredients of brown corundum, have a certain impact on the grinding performance and fire resistance, and the appearance is not very beautiful and affect the end user's experience. In particular, some fine grinding industries have extremely high requirements for the quality of brown corundum, and these impurities may cause defective products in the final product.
These white impurities are difficult to completely remove because they are produced during the smelting process, and there will be a certain content in the brown corundum block. In actual production, the following methods are mainly used to minimize the appearance of white spots.
1.Raw material optimization and smelting, purification improve the crystallization effect of brown fused alumina, making the brown fused alumina denser and less impurity from the source
2.In the crushing process, manually sorting, try to select the original pieces with less impurities to crush the silt. But this method is labor intensive and costly
3.Multiple magnetic separation treatments can remove impurities containing more iron and magnetic substances

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