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The change of water occurrence form and content in coal will change the physical characteristics and pore structure of coal, and then affect its crushing process.In order to study the effect of moisture contained in coal on on the crushing behavior of coal particles,anthracite coal was used as the research object. A Hastelloy grinding equipped with a power measuring device was applied to simulate the crushing environment in a medium-speed coal mill. The individual and mixed crushing experiments were carried out in multi-time batches of coal samples with different water content. Thus, the effects of water occurrence on coal crushing rate, pulverized coal fineness, and grinding energy consumption were studied. The experimental results showed that compared with the original coal samples, the initial particle size material crushing rate of homogenized soaked coal samples decreases significantly due to the increase of water content, its grindability index first decreased and then increased with increasing the water content when the homogenized immersed coal sample was crushed separately, and the fineness of pulverized coal t10 was positively correlated with water content. When dry and wet coal samples were mixed and crushed, the crushing rate and fine-grained material generation rate of 13.34% moisture content samples were much higher than that of homogenized soaked coal samples with the same moisture content, and their its grindability index was larger than that of the original coal; The grindability index of the blended coal samples with other moisture contents was slightly smaller than that of the homogenized soaked coal samples, and this difference became larger with the increase of moisture content, while the crushing rate and the yield of fine-grained materials differed less from that of the homogenized impregnated coal samples. Also, the result indicated that the classical energy-particle size relationship model may be used to characterize the individual and mixed crushing processes of samples with different moisture gradients. The internal and external moisture reduced the ability of anthracite to resist crushing to varying degrees, and increasing the water content during separate crushing improved the energy efficiency significantly. So, the water content parameters were introduced into the energy consumption model to characterize the crushing process of various moisture coal samples. By exploring the influence mechanism of water content in coal on energy consumption of coal crushing, it reveals the way of energy loss in the process of coal crushing and provides theoretical guidance for optimizing coal crushing process and reducing energy consumption.

The Taixi anthracite was used as the raw materials, and mixed with different masses of additives, namely silicon oxide, titanium oxide, and iron oxide, to prepare the coal-based graphite by high temperature graphitization. The microstructure of coal-based graphite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), laser confocal Raman spectroscopy (Raman) and Specific surface area and porosity analyzer.The results show that the graphitization degree of the coal-based graphite can reach over 89% after high temperature heat treatment at 2800 °C , which significantly improves the microcrystalline structure of anthracite and achieves orderly rearrangement of sp2 hybrid carbon atoms in the coal. Under the same additive mixing level, the graphitization degree and stacking height of coal-based graphite with titanium dioxide as additive are relatively high, the difference between the layer spacing and the ideal graphite layer spacing is the smallest, and the degree of ordering of carbon materials is the highest. The Raman spectroscopy results showed that the order degree of coal -based graphite prepared under different additives was significantly different, and the order degree of TXSC3, TXTC2 and TXIC3 coal-based graphite was the highest among the additives. Under the electron microscope, it is found that under the conditions of three additives, the scales, spherical and two shapes of coal-based graphite can be prepared separately. It can be seen from the specific surface area and pore size distribution data of coal-based graphite that they have similar low-temperature nitrogen adsorption-desorption isotherms.

Lignite is extremely hydrophilic; thus it is difficult to upgrade its quality by conventional flotation. In this study, cetylpyridinium chloride monohydrate (CCM) was used as the collector for quartz. The effect of CCM dosage on reverse flotation of Shengli lignite was investigated by different slurry mixing methods. And the dissolution properties of CCM and its mechanism of collecting quartz were studied via surface tensitometer and FTIR. The flotation results show that, due to the strong hydrophilicity of Shengli lignite, the performance of direct flotation is poor. With reverse flotation, the yield of clean coal and the flotation perfection are obviously improved. Besides, the reverse flotation with the zero-conditioning is more efficient than the conventional one. FTIR results show that the adsorption of CCM barely change the functional groups of quartz, indicating that CCM was adsorbed on the surface of quartz through electrostatic adsorption to collect quartz. Meanwhile, CCM adsorption significantly reduces the content of hydroxyl oxygen-containing functional groups of quartz, leading to an increase of the content of hydrophobic groups such as long-chain alkyl. As a result, the hydrophobicity of quartz was improved, and the reverse flotation of lignite was promoted.