Research Of Goaf Spontaneous Combustion Danger Zone Change Law With U+L Ventilation

This study aimed at the actual situation of Suancigou coal mine 107 face of 6 upper of Yitai Group, study the impact of goaf spontaneous combustion danger zone on 107 face of 6 upper under the U+L ventilation with a link-roadway is not closed on the side for return air in goaf, and study the change of goaf dangerous areas with different air supply amount in order to eliminate the goaf fire hazards and provide theoretical basis. Establishing beam tube monitoring system on 107 face of 6 upper and analyzing the oxygen concentration in goaf and on the basis of oxygen concentration to partition goaf spontaneous combustion "three zones"; In order to contrast with U+L ventilation style, also establish beam tube monitoring system on 109 face of 6 upper and partition goaf spontaneous combustion "three zones"; Application of numerical simulation software COMSOL, establishment of two-dimensional model, simulating U+L ventilation style when link-roadway into the goaf is apart from the face distance is different to the impact of goaf spontaneous combustion danger zone; In addition, simulating the goaf spontaneous combustion danger zone under different air supply amount between U+L and U ventilation style, and analyzing all kinds of situation. Finally to simulate nitrogen injection in goaf, according to the simulation results analyzing the impact of nitrogen injection in goaf of spontaneous combustion danger zone, to provide guidance for the establishment of goaf fire security measures, and get the effective prevention of goaf spontaneous combustion.