浅埋特厚煤层采空区自燃“三带”分布规律研究

Study on the Distribution Law of Spontaneous Combustion Three Zones in Goaf of Shallow Buried Extra-thick Coal Seam

为了研究浅埋特厚煤层综放工作面采空区自燃“三带”分布规律,以中煤平朔井工三矿39204工作面为研究对象,通过现场监测、数值模拟、理论分析等多手段相结合方法,基于氧气浓度划分标准对采空区自燃“三带”分布特征和最低推进速度进行了研究。结果表明:现场监测所得采空区自燃“三带”分布范围和数值模拟试验结果相近,相对误差较小,其中进风巷散热带、自燃带和窒息带长度分别为0~31.5 m、31.5~80和80 m以上,回风巷的散热带、自燃带和窒息带长度分别为0~20.5 m、20.5~55.9 m和55.9 m以上,依据所得采空区自燃“三带”划分结果和最短自然发火期,计算确定了39204工作面每天推进长度应大于1.02 m,每月应大于30.6 m,可避免采空区遗煤发生自然现象,若推进长度小于计算值则需采取相关措施进行自然发火预防。

39204 working face of No.3 Mine of China Coal Pingshuo was taken as the research object,and the distribution characteristics and minimum advance speed of "three zones" of spontaneous combustion in goaf were studied based on the oxygen concentration classification standard through the combination of on-site monitoring,numerical simulation,theoretical analysis and other means.The results showed that the distribution range of the three zones of spontaneous combustion in the goaf obtained from on-site monitoring was similar to the numerical simulation test results,with relatively small errors.The lengths of the heat dissipation zone,spontaneous combustion zone,and suffocation zone in the intake airway were above 0~31.5,31.5~80 and 80 meters.The lengths of the heat dissipation zone,spontaneous combustion zone,and suffocation zone in the return airway were above 0~20.5,20.5~55.9 and 55.9 meters.It was calculated that the daily advance length of the 39204 working face should be greater than 1.02 meters,and the monthly advance length should be greater than 30.6 meters.