Study on enrichment characteristics of gallium in coal

In order to explore the enrichment characteristics of gallium and minerals in coal preparation process, Pingshuo high ash and high sulfur coal is taken as the research object.The products of different size range of separation and density fraction and their ash products are prepared by size analysis, float-and-sink test.And the minerals and gallium elements in the products are analyzed by chemical method and X-ray diffraction method respectively.The results show that the concentration of gallium in ash of the same test sample is much higher than that of the test sample itself, and the enrichment ratio is 1.12-11.78.The enrichment effect is achieved by combustion, especially in the range of small particle size and small density, the concentration of gallium in coal ash is high, and the enrichment ratio is 3.36 and 11.78 respectively.In addition, the concentration factor EF of gallium in the test samples before and after coal combustion is within the range of 0.4-0.85, which indicates that gallium is highly correlated with ash.Further analysis of the correlation between gallium and minerals shows that gallium is mainly concentrated in kaolinite and boehmite.The correlation coefficient between gallium and andalusite is 0.797, which indicates that gallium migrates from kaolinite to andalusite during combustion.