采空区注氮防灭火技术的优化设计及工艺改进

Optimization Design and Technological Improvement of Nitrogen Injection Technology for Fire Prevention in Goaf

为降低遗煤自燃危险性,增强注氮防灭火效果,通过模拟分析不同注氮位置、注氮量下采空区氧浓度分布情况,确定最佳注氮量为1400 m^(3)/h、注氮位置为距工作面40 m处;将注氮工艺由间隔式改为非间隔式注氮工艺,并采用悬挂挡风帘、搭挡风墙措施可防止氮气的流出。改进后,采空区内CO浓度先增大后降低,且进回风巷CO浓度均小于最高CO浓度0.024‰,表明该注氮工艺能够抑制采空区煤的自燃氧化。进遗传算法优化双环管网案例和河内管网案例,与多种算法对比,证明了改进遗传算法在实际应用中的可行性。

In order to reduce the risk of spontaneous combustion of residual coal and improve the effect of nitrogen injection on fire prevention.The distribution of oxygen concentration in goaf under different nitrogen injection positions and nitrogen injection amounts was simulated and determined that the optimal nitrogen injection amount was 1 400 m^(3)/h and the nitrogen injection position was 40 m away from the working face.The process of nitrogen injection is changed from interval type to non-interval type.At the same time,the measures such as hanging windscreen and building baffle wall are used to prevent the outflow of nitrogen.After the improvement,the CO concentration in the gob increases first and then decreases,and the CO concentration in the inlet and return air is less than the maximum CO concentration of 0.024‰,which indicates that the nitrogen injection process can inhibit the spontaneous combustion and oxidation of coal in the gob.