Fire Prevention Technology Practice in Syncline Structure Area based on Inhibitor Spraying and Tube Bundle Monitoring

Abstract

To address the “water-gas-structure” multi-field coupling disaster encountered by the 9401 fully mechanized top-coal caving face at Hengsheng Coal Mine while passing through the Liujiazhuang syncline axis, the three-dimensional compound air leakage mechanism composed of “boreholes, overlying goaf, and surface fissures” and the associated risk of residual coal spontaneous combustion were analyzed in depth. Consequently, an active prevention and control system centered on mobile calcium chloride inhibitor spraying was constructed. A calculation model for the inhibitor dosage based on mining parameters was established, determining the optimal daily spray volume at 9.98 m³, accompanied by the implementation of a hierarchical dynamic control strategy. Combined with a beam tube monitoring system, full-process dynamic tracking of key gas components in the goaf, including O₂, CH₄, CO₂, and CO, was conducted. Field application results indicated that during the implementation, the gas flow field in the goaf remained generally stable. The peak methane concentration was controlled below 0.55%, and carbon monoxide levels consistently remained at low background values without abnormal fluctuations. This system effectively blocked compound air leakage channels, inhibited the oxidation process of residual coal, and ensured safe mining operations under complex geological conditions.