Research on prevention and control technology of mineral spontaneous combustion in Fushun West Open Pit Mine

In view of the frequent occurrence of spontaneous combustion disasters in the Fushun West Open Pit Mine and the resulting problems of environmental pollution and production safety, three samples of coal, kerogen shale, and retorted kerogen shale are taken on-site to conduct laboratory industrial analysis and high-temperature programmed heating experiments, respectively. The results of industrial analysis and the rules and heat release characteristics of gases released during the spontaneous combustion process are obtained, the mechanism of spontaneous combustion of minerals is studied, and the monitoring methods and appropriate prevention and control technical measures for spontaneous combustion in open pit mines are proposed. The results show that the volatile matter of coal samples is the highest, reaching 42%, while the ash content of oil shale and dry distillation residue both exceed 75%. The specific surface area and pore size distribution show that the mixed minerals are prone to oxidation and adsorption, and the apparent structural characteristics explain why the minerals are prone to oxidation and spontaneous combustion. During the oxidation and heating process of each sample, carbon oxides and hydrocarbons are easily precipitated, and the composition and concentration of the gas are closely related to the temperature. The oxidation heating process releases huge amounts of heat, which promotes the further development of self-heating to spontaneous combustion. Spontaneous combustion in open pit mines not only affects the ecological environment, but also destroys high-quality coal resources, reduces slope strength, and may further trigger geological disasters such as landslides. An infrared thermal imaging system can be used to accurately delineate high-temperature self-heating and spontaneous combustion areas by combining auxiliary isotope radon measurement and borehole temperature measurement, so as to select appropriate prevention and control measures for precise management, effectively controlling the development of spontaneous combustion in the mine, and treating similar problems. Precise prevention and control of spontaneous combustion in mines provides reference experience.