Distribution of 'three zones' of spontaneous combustion in gob with lower entry retained along the gob

摘要

CT101 of Wugou Coal Mine is a fully mechanized longwall.The goaf is filled with gangue.Along the gob side the lower entry is retained by constructing a piled wall of trapezoidal gangue bags.The retained entry is ventilated by a local fan with positive pressure.In order to understand the "three zones" distribution in the gob so as to provide the basis for fire prevention, temperature probes and gas exhausting pipes were embedded in the gob along the upper entry and behind supports.Temperature and oxygen concentration at different sites were obtained.Based on the rate of temperature rise and oxygen concentration changes, "three zones" features in the gob were obtained: The "three zones" change fast with time.The heat dissipation zone is very narrow, the widest position of the heat dissipation zone and the oxidation zone are in the triangle strip formed by hydraulic supports and the wall of gangue bags.