The inducement of coal spontaneous combustion disaster and control technology in a wide range of coal mine closed area

Based on the theory of coal and oxygen interaction mechanism and combined with the actual situation of a coal spontaneous combustion incident at Wangtaipu coal mine, the occurrence conditions, process, and the degree of risk of spontaneous combustion in the closed area are analyzed in detail. The main reasons for the coal spontaneous combustion in the closed area were obtained by the extraction and analysis of the multiinformation. The fractures on the seal walls were analyzed. Their distribution characteristics and air leakage were investigated. According to the distribution concentration of CO and O-2 and their variety law in the entire closed area, the range of the fire zone was delineated. After that, multiple technical measures were implemented, such as fracture plugging, even pressure for air control, and absorbing and cooling temperature by injecting nitrogen. The concentration changes of CO, O-2, and CO2 in the closed area are controlled, and the temperature and pressure difference are obviously reduced. The use of multiple information to analysis the degree of spontaneous combustion in the closed area and the multiple fire extinguishing technology has been demonstrated successful in the practical application. The proposed techniques can be applied to other similar conditions for prevention and control of hazards imitated from coal spontaneous combustion.