注惰对封闭火区可燃性气体运移规律影响的研究

Effect of Inert Gas Injection on Transport Law of Combustible Gas in Closed Fire Zone

注惰是矿井火灾救灾措施之一,但在救灾实践中向封闭火区注惰却诱发了爆炸,因此研究注惰对封闭火区可燃气体运移规律的影响十分必要。从理论上分析了封闭火区内发生的化学反应和气体组分,并依据质量守恒定律建立了封闭火区内气体浓度的数学模型和注入惰气后气体浓度变化的数学模型;设计、实施了封闭巷道内充注惰气模拟实验,实验结果证实矿井火灾可产生H2和烷烯烃类化合物等可燃性气体;通过对实验数据中O2、CO注惰前后浓度变化分析得出,充注惰气对封闭火区可燃气体具有改变风流流动状态的"活塞"推动作用;通过对比注惰前后CO理论计算值和实验测试值验证了理论分析和数学模型的可靠性。研究结果对于煤矿火灾救灾过程中防止次生灾害的发生具有重要意义。

It is one of methods to prevent coal mine fire with inert gas,however, it has induced gas explosion when the inert gas was injected into closed fire zone. Therefore, it is very necessary to know the combustible gas movement behavior after inert gas injection in closed fire zone. The chemical reaction and gas component is analyzed theoretically, and the mathematical model is found for gas concentration of closed zone before or after injected according to the principle of conservation of mass. A simulated experiment is designed and conducted for injected inert gas into dosed laneway. Based onthe experimental result, the combustible gas, such as H2 alkane and olefin, is formed during coal mine fire. Furthermore, it is indicated that the inert gas push combustible gas, like ＂piston＂, which can change the direction of ventilating current, from the O2 ,CO concentration analysis before or after injected. Through a comparative analysis of practical monitoring data and value in theory about CO, the theoretical solution and the mathematical model is proved to be reliable. These results have important significance for prevent secondary accident in coal mine fire extinguished.