关键词: 高瓦斯近距离煤层群, 煤层自燃, 回撤密闭期间, 综合防灭火

Abstract: :High gas mine working face is prone to spontaneous fire during stoppage of production and removal of support, thus causing gas explosion.There are some spontaneous combustion characteristics such as serious air leakage in the goaf, high temperature fire area near the goaf, and more residual coal in the goaf, etc. Nitrogen injection, grouting, wind plugging, spontaneous combustion prediction and other fire prevention were implemented.The gas monitoring results showecd that during the end of mining and removal of supports, the volume fraction of CO and O2 showed a trend of first low, then high and then low, and the CH4 volume fraction ranged from 0.5% and 1.3%.After air stopping, the concentration of CO and O2 ranged from 1×10-6 ~ 11×10-6 and 0.01% ~ 0.09% respectively.The concentration of CH4 ranged from 0.24% ~ 1.48%, it showed that comprehensive fire-fighting technology has a good inhibiting effect on the spontaneous combustion of goaf coal. The gas concentration of CH4 is in a safe range, which ensured the safety of the working face production.