Abstract:
In order to study the law of coal spontaneous combustion in high-gas coal mines, the No.4 coal seam at 302 face of Tingnan Coal Mine was used as the research object. We analyze the “three-zone” law of spontaneous combustion in the district, and through comparative analysis, the results of the “three-zone characteristic” of spontaneous combustion in high-gas mines show that the lower limit oxygen concentration of No.4 coal seam in Tingnan Coal Mine is 8.0%, and gas products show a “hysteresis effect” with the decrease of oxygen content; the oxidation zone of goaf is asymmetrical in tendency. The inlet side is wide and the maximum width is 95 m. The return air side is narrow(77 m). Compared with the “three zones” of 1# to 4# goaf, the width of the loose tropical zone of 302 working face goaf is larger and the return air side is smaller, and the maximum width of the oxidation warming zone of the inlet and outlet air side is smaller. During the normal stoping period, the main threat of coal spontaneous combustion comes from the “two roads” floating coal in the goaf.