Research of the air leakage law and control techniques of the spontaneous combustion dangerous zone of re-mining coal body

The float coal in the gob of re-mining face spontaneous combustion mechanisms was studied and the physical model was build. With the boundary condition determined by analyzing the on-the-spot data, the distribution of oxygen concentration and the velocity of air flow in the gob were calculated by numerically simulating the flow field. Basis on the results,a type of composite gel was chosen to used controlling the development of the spontaneous combustion dangerous zone,at the same time,the characteristics and form of the gel was introduced,and showen the equipments and systems of injectting gel.The spontaneous combustion zone was controlled after injecting the composite gel with fly ash,with the temperature and CO gas reducing.