综放工作面“U+Ⅰ”通风系统与煤自燃的关系

The Relationship Between 'U+Ⅰ' Ventilation System of Fully Mechanized Top Coal Caving Face and Coal Spontaneous Combustion

分析了综放工作面"U+Ⅰ"型通风系统的特性,推导了该系统各条巷道的配风关系式,考察了高位巷通畅与堵塞时期"U+Ⅰ"型通风系统的风排瓦斯效率,并结合2005年神华宁夏煤业集团公司乌兰煤矿5344工作面的"4.8"火灾案例,运用数值模拟的方法分析了"U+Ⅰ"型通风系统高位巷阻塞或通畅对采空区氧浓度场的影响。研究表明:高位巷阻塞期间风排瓦斯效率变低,上隅角瓦斯浓度升高,氧化升温带在回风侧离工作面较近且范围更大。研究结果对于防治工作面瓦斯超限和采空区煤自燃具有十分现实的指导意义。

In this paper,the ＇U＋Ⅰ＇ ventilation system＇s characteristics of fully mechanized top coal caving face have been analyzed and the air distribution formula of each roadway deduced.In addition,gas drainage efficiency of the ＇U＋I＇ ventilation system was investigated when the elevated lane was both blocked and unobstructed.And more specifically,the differences of the oxygen concentration field in the goaf caused by the elevated lane＇s state of the ＇U＋Ⅰ＇ ventilation system were studied with numerical simulation method and by combining the mine fire case dated April 8,2005 at the working face 5344 of Wulan Coal Mine,Shenhua-Ningxia Coal Industry Group.The research shows that if the elevated lane is blocked,the gas drainage efficiency would become lower and gas concentration at upper corner of working face would become higher.Besides,the oxidization and heat accumulation zone would be expected to be larger than before and nearer to the working face in the exhaust section.The results achieved may serve as a guidance to solve gas overrunning problem at work face and prevent coal spontaneous combustion in the goaf.