Comprehensive Protection and Control Technology for Coal Spontaneous Combustion at Fully Mechanized Caving Face in Yanzishan Coal Mine

During the mining period of No.8901 fully mechanized caving face in Yanzishan Coal Mine, gases including CO, C₂H₄ and C₂H₂ appeared in the goaf, concentrations of which fluctuated severely, and C₂H₂ emerged intermittently. By analyzing this situation, it was concluded that it occurred coal spontaneous combustion in the goaf mainly because of the large air leakage from upper goafs and small pit goafs. Therefore, a comprehensive fire protection technology was put forth and applied for controlling spontaneous combustion during mining and closing period of No.8901 fully mechanized caving face which involved pressure balancing ventilation, sealing air leakage, nitrogen injection in goaf, and ground concentrated grouting, it had achieved good effects. This technology can be used for reference to control goaf coal spontaneous combustion under similar conditions.