Research On The Coal Spontaneous Combustion Dangerous Area Division And Nitrogen Injection Simulation In Yang Village Mine Fully Mechanized Goaf

The spontaneous combustion of coal in goaf seriously affect the mine safety in production. Which can cause dust and gas explosion, and lead to major fatal casualties accidents. Yang village Mine 316 fully mechanized caving face is located below the Si east bank, in order to prevent damage to the aquifer, the annual flood season need to stop mining, which is belong to intermittent mining. Daily average forward speed is relatively slow, while 316 mechanized caving working face belongs to intermittent, longer stop mining, coal left exposed to oxidation temperature zone for too long, increasing the goaf risk of spontaneous combustion of coal, mined in need strengthen the mined-out area of monitoring and prevention during stop mining.This paper from intermittent mining characteristics in Yang village mine 316 fully mechanized goaf, adopting spontaneous combustion experiment research, field observations, numerical simulation of spontaneous combustion danger zone determination, the distribution of nitrogen injection on oxygen concentration during different field numerical simulation.First of all, the natural characteristics, the influence factors of coal spontaneous combustion and the division of “three zones” are studied. Secondly, through the combination of the coal spontaneous combustion experiment and the field monitoring data, the “three zone” division and the determination of the spontaneous combustion danger zone of the goaf are carried out. Finally, the physical model is established according to the actual conditions at the site, in based on the measured parameters, according to the theory of porous media, combined with spontaneous combustion experiment show that the consumption rate of oxygen and energy conservation equation, transfer equation, turbulence model. Using Fluent calculation software simulation gob oxygen concentration field, verify the reliability of the model. Comprehensive analysis showed that during the normal exploitation of the best location,and oxidation temperature zone meet safety distance, in the nitrogen injection at the inlet side of 40 m, heat and oxidation temperature at the junction with the belt; reasonable nitrogen injection of 400m3/h; during stop mining, the bandwidth requirements minimize oxidation degree warming in the 30 m at the continuous injection of 400m3/h nitrogen is more reasonable. The results of the study could for 316 mechanized caving working face of fire prevention and control to provide certain theoretical basis and effective prevention of goaf left coal spontaneous combustion.