某煤矿综放采空区瓦斯与火治理技术

Gas and Fire Control Technology in Fully Mechanized Caving Goaf of a Coal Mine

某矿综放工作面放顶煤开采会使采空区遗留大量煤炭,采空区在采取瓦斯抽采措施时,会导致工作面风流漏入采空区,导致采空区内风流场变化,进而增加采空区自燃危险性。针对此问题,使用FLUENT数值软件建立了采空区自燃危险区仿真数值模型,计算得到工作面适宜风量为1200 m^(3)/min,抽采量为140 m^(2)/min,注氮量为1000 m^(3)/h,确定工作面最小推进速度为2.05 m/d。经现场检验,抽采纯量为15 m^(3)/min,风排量为4 m^(3)/min,采空区深部CO最大值在2~23 ppm,较好地兼顾了瓦斯与火治理。

The top coal caving mining in the fully mechanized caving face of a mine will leave a large amount of coal in the goaf.When the goaf is taken gas drainage measures,it will lead to the air leakage of the working face into the goaf,resulting in the change of the air flow field in the goaf,thereby increasing the risk of spontaneous combustion in the goaf.In view of this problem,the FLUENT numerical software was used to establish the simulation numerical model of goaf spontaneous combustion danger zone.The suitable air volume of working face was 1200 m^(3)/min,the extraction amount was 140 m^(3)/min,and the nitrogen injection amount was 1000 m^(3)/h.The minimum advancing speed of working face was determined to be 2.05 m/d.According to the field test,the pure volume of extraction is 15 m^(3)/min,the wind discharge is 4 m^(3)/min,and the maximum value of CO in the deep part of the goaf is 2~23 ppm,which better takes into account the gas and fire control.