Study On Mechanism Of Waste Rock Spontaneous Combustion And Fathering Technology In Dongrong No.2 Coalmine

Wastrock spontaneous combustion seriously threatened safety production and contained the environment in coalmine. After long term development, spontaneous fire zone in the wastrock piles in Dongrong No.2 mine got the characteristics of high temperature and large range, which threatened safety production of the enterprise seriously.In the present study, influence of characteristics of the wasterock, including sulfer content, carbon content and deteroprate degree, water content and stacking property, on spontaneous combustion are stuied. Through wasterock fire site monitoring and theoretical analysis, it proved that there exist not only coal oxidation bu also gasification (reaction of coal with carbon dioxide and water vapor). The reason of explosion during drenching water into the high-temperature fire zone int the wastrock pile is analyzed systematically. Through analyzing mass transfer in the wasterock pile, a model for regulation of gas penetration and development of the fire is set up.According to characteristics of the wasterock spontaneous combustion, a general technique scheme to extinguish the fire is put forward. The fire is extinguished successfully by means of injecting composite gel into the fire zone, which safeguarded safety production and improved the environment in the coalmine.It proved that the composite gel can absorb large amount of heat and plug air leakage passages, which suits for extinguish wasterock pile fire well. The composite gel makes full use of fly ash from the nearby power station, which not only reliefed environmental pollution by the waste ash but also reduced cost of the fire-fighting material. The fire extinguishing system realized injecting gel in large flux and got very good fire extinguishing effect.