Analysis on the determination of spontaneous combustion risk areas in goaf under three-dimensional gas extraction in the coal industry
The oxidation and spontaneous combustion of coal must meet the following conditions simultaneously:① The coal seam has a tendency towards spontaneous combustion and accumulates in a fragmented state;②Continuous ventilation and oxygen supply conditions;③ Continuous thermal storage environment;④ sufficient oxidation time.Whether using coal pillar mining or no coal pillar mining,there is always air leakage in the goaf behind the working face.The range of air leakage is not only affected by the lithology of the roof and the method of roof caving,but also by the speed of the working face and the compaction time of the caving rocks in the goaf.The magnitude of air leakage velocity directly affects the oxygen supply and heat storage conditions of coal.The concentration of oxygen determines the oxidation and spontaneous combustion ability of coal seams,while the advancing speed of the working face determines the duration of floating coal oxidation.Therefore,goaf areas with spontaneous combustion tendency fully have the conditions for spontaneous combustion.
Spontaneous combustion three zonesOxidation zoneNegative pressureCOMSOL software
万方数据
维普
