Rong Liu

During the mining process of open-pit mines, multiple operations are prone to generating dust, especially during the blasting, where a significant amount of dust is raised and subsequently deposited on the surface of the blast pile. The impact of the blasting force further saturates the interior of the pile with dust. Subject to the combined effects of natural wind and shoveling operations, this dust is re-suspended and disseminated throughout the mine pit, posing a significant threat to the safe operation of the mine and the health of workers. This study comprehensively utilizes field testing and numerical simulations to delve into the migration characteristics of blast pile dust under the combined influence of wind and shoveling operations. Attention is paid to the effects of different wind speeds, wind directions, and shoveling operations on the distribution and migration trajectory of blast pile dust. The research results indicate that the movement of dust is primarily controlled by wind flow, determining its ultimate migration path and diffusion range. This study not only provides a significant theoretical foundation for precise prevention and control of dust pollution in open-pit mines but also has vital practical significance for enhancing the safety of mine operating environments and safeguarding the physical and mental health of workers.

Salt rock is considered as an ideal energy storage medium, and compressed air energy storage by a salt cavern can improve the utilisation efficiency of renewable energy. Salt rock in China mostly contains different interlayers, among which mudstone interlayers are the most common. At present, there are relatively few studies on the influence of mudstone interlayers on the long-term stable operation of gas storage. FLAC3D software was used to simulate the long-term operation of salt rock gas storage with different numbers of interlayers in the Yexian area of Pingdingshan. The results show that with the passage of time, the vertical displacement of the surrounding rock of the vertical single-cavity gas storage tank increases gradually. The maximum settlement value at the top of the surrounding rock is always greater than the maximum uplift value at the bottom. The horizontal displacement shows obvious symmetry with the vertical displacement at the top and bottom of the surrounding rock. The effect of the cyclic pressure interval on horizontal displacement is the same as that of vertical displacement. With the increase in the number of interlayers, the volume of the plastic zone gradually increases with the increase in the running time, and the increasing speed shows a growing trend.

Coal dust pollution in fully mechanized excavation faces not only affects the safety production of the coal mine but also threatens the health of workers. In order to reduce coal dust pollution and improve work conditions in mines, the layout of the dedusting-air duct in the dry dust collector and the influence of the duct position on the dust-producing area were studied. In addition, the effects of different cutting positions on dust removal efficiency were also studied. A full-scale model of mine roadway is established by CFD, and the influence of the position of the dedusting-air duct on dust diffusion and the distance between the tunneling head and the dedusting air duct on dust removal efficiency are studied. The results show that the higher the cutting position, the higher the dust concentration, and the longer the dust diffusion time in the coal roadway. When the distance between the dedusting-air duct and the tunneling head is set to 4 or 5 m, the dust removal efficiency is the highest. Moreover, the dust removal efficiency of the dry dust collector with the dedusting air duct arranged on the opposite side of the roadway is higher than that of the collector with the duct in the middle of the roadway.