下分层工作面煤自燃早期辨识与防治

难胶结人工顶板层状漏风诱发煤体自燃是下分层工作面巷道掘进及生产过程中防灭火难题。针对煤自燃初期气体产物量小易受风流稀释而难以检测的问题，在向下分层煤层顶板布置专用测试装置，监测煤体内部气体的温度和气体成分，判定煤自燃状态。研究结果表明，煤体内测点最高可检出175×10^-6，巷道风流仍不能及时发现煤氧化气体产物；易自燃下分层煤体因二次氧化，自燃进程快，监测煤体内部气体能够实现煤自燃的早期辨识；煤层顶板冒落岩石胶结程度低，形成平面漏风是下分层煤体自燃的直接原因，通过向上分层采空区沿煤层走向注入高分子材料形成漏风封堵墙，有效控制了下分层煤体的自燃。

Early identification and prevention of coal spontaneous combustion in lower stratified face

Spontaneous combustion of coal body induced by layered air leakage of difficult-to-cement artificial roof is a difficult problem in fire prevention and fire prevention in the process of tunnel excavation and production in the lower layered working face.Aiming at the problem that the amount of gas products in the initial stage of coal spontaneous combustion was small and was easily diluted by wind flow and was difficult to detect,a special test device was arranged on the roof of the downward stratified coal seam to monitor the temperature and gas composition of the gas inside the coal body to determine the coal spontaneous combustion state.The research results showed that the highest detection point in the coal body could detect 175×10^-6,and the air flow of the roadway still could not detect the coal oxidation gas products in time;the gas inside the coal body could realize the early identification of coal spontaneous combustion;the coal seam roof caving rock had a low degree of cementation,and the formation of plane air leakage was the direct cause of the spontaneous combustion of the lower layered coal body.The sealing wall effectively controled the spontaneous combustion of the lower layered coal body.