Experimental Study Of Remaining Coal Spontaneous Combustion Law In Goaf For Majialiang Coal Mine

Majialiang Coal Mine is located in Shuocheng territory in Shanxi Province, The mine design production is 12 Mt/a, by use of mining overall height of fully mechanized caving coal face mining technology. The average thickness of extraction of 4 # coal seam is 9.8m, all the face width is 250 m, to around 2500 m in length. However, due to the technology features, fully mechanized caving mining brings about a big falling goaf space,more air leakage channel and air leakage volume, more coal in goaf and the goaf is often affected by the roof water.These factors in time and space lead to the increased the difficulty to master the goaf fire.Taking Ma Jia Liang coal mine fully mechanized caving mining working face as the project background, analysis the impact of necessary and sufficient conditions of coal spontaneous combustion,aimed to establish "fire prevention——fire prediction——fire emergency" three in one comprehensive fire prevention technology system. The main research contents are as follows:(1)Through the coal spontaneous combustion programed heating test for different water content to determine the spontaneous combustion characteristics of coal goaf under aqueous conditions, master of residual coal spontaneous combustion index gas, establishment coal spontaneous " fire prediction " system;( 2) Through the spontaneous combustion "three zone" experiment platform,explore the correlation between stope ventilation quantity and spontaneous combustion "three zone" range;(3)Through the continuous observation for the whole progress of cutting and caving coal,analysis residual coal distribution in goaf; through the determination of stope ventilation condition of site, analysis air leakage distribution in goaf.Based on these, to determine the residual coal in the goaf spontaneous combustion rule.(4)According to the spontaneous combustion rules of residual coal in goaf,put forward the working face end stacking block wall technology, reduce the internal goaf air leakage,put forward the injection of nitrogen technology, reduce the oxygen content in mined-out area,based on these to establish pontaneous combustion "fire prevention" system.;According to the different emergency situation, proposed a low-temperature nitrogen resistance of water mist technology, liquid nitrogen pouring technology of fire prevention, establish goaf spontaneous combustion "emergency fire extinguishing" technology system.