Fire Extinguishing and Unsealing Technology of Spontaneous Combustion in Goaf of High Gassy and Easy Combusted Thick Seam

In order to ensure a safety unsealing of the combustion zone in the high gassy and easy combusted thick seam and the safety mining of the fully mecha nized top coal caving mining face, based on the spontaneous combustion features of No.8101 top coal caving mining face in Tongxin Mine, from the coal distribution in t he goaf of the coal mining face, coal mining face advancing rate, ventilation leakage quantity and others, the paper analyzed the combustion features.The oxidization C onditions and high temperature range of the fire zone were detected.The results showed the fire zone after unsealed would have a possibility of re-combustion and the「 elated technical measures to prevent the re-combustion should be conducted.The fire prevention and control technology with nitrogen and carbon dioxide should be app lied to control the sustainable expansion of the fire zone in the goaf, and the fire prevention and control technology with pressurized injection of fly ash should be applie d to extinguish the high temperature fire source in the goaf, and to form a fire isolation zone to effectively isolate the fire zone in the goaf in order to provide good condi tions to successfully unseal the spontaneous combustion zone in the goaf and to ensure the normal production recovered of the coal mining face.