Goaf Spontaneous Combustion Forecast under Conditions of Stereoscopic Gas Drainage(Extended Abstract)

摘要

In order to avoidgoaf accidents caused by gassy and high spontaneous combustion, spontaneous combustion oxidation experiment was carried out under the conditions of air flow with various gas concentrations, at the same time, considering the "U+L+I" type ventilation system characteristics of Tianchi coal mine 401 working face, numerical simulation and field measurement was used to investigate the law of goaf air leakage under the conditions of stereoscopic gas drainage and spontaneous combustion prediction method was established.Furthermore, under the process of oxidation temperature rising, CO concentration was calculated in the way of one-dimensional linear difference calculation.Then the risk index of 401 working face of spontaneous combustion was obtained.The research shows that under the conditions of air flow with various gas concentrations, oxidation product CO shows "lag effect".We can predict the goaf spontaneous combustion danger by using high pumping lane and tail lane gas composition under the conditions of stereoscopic gas drainage.In 401 working face, when pumping high lane CO concentrations are less than 74 ppm and tail lane CO concentrations are less than 37 ppm, goaf will be in the low-temperature oxidation stage; when high pumping lane CO concentrations are greater than or equal to 74 ppm or tail lane CO concentrations are greater than or equal to 37 ppm, goaf will be in the spontaneous combustion dangerous stage.The research results may have practical significance for gas prevention and spontaneous combustion control of gassy and high spontaneous combustion coal seam.