气液两相介质抑制管道甲烷爆炸协同增效作用

Synergistic inhibition effect on methane explosion in pipeline by gas-liquid two-phase medium

瓦斯抽采管道一旦泄漏或受到外部火源波及,极有可能引发爆炸事故。基于自行搭建的惰性气体-超细水雾惰化抑制可燃气体爆炸试验系统,研究了气液两相介质抑制9. 5%甲烷/空气预混气爆炸的影响因素和协同作用规律,并分析了其抑爆协同增效的原因,提出气液两相介质抑爆存在相间耦合作用。实验结果表明:在CO_2,N_2,He和Ar四种惰性气体与超细水雾的共同作用下,气液两相介质对9. 5%甲烷/空气预混气爆炸超压、火焰传播速度和最大火焰温度的抑制均表现出明显的协同增效作用。当4种惰性气体稀释体积分数达到14%、细水雾通入量8.4mL(质量浓度694. 4 g/m^3)后,均能对9. 5%甲烷/空气爆炸产生良好的抑制效果;控制参数继续增加,抑爆增效作用的增长幅度缩小;其中CO_2与超细水雾下的协同抑爆效果最好,N_2次之,He,Ar与超细水雾的协同抑爆水平相差不大,为清洁、高效惰化细水雾抑爆技术的应用提供了技术指导。

At present,there are a large number of methane transport pipelines.Once the gas drainage pipes leak or are affected by external fire,it is likely to cause an explosion accident.Based on the self-built inert gas/ultra-fine water mist inerting suppressing test system on gas explosion,this paper carried out a series of gas-explosion inhibition experiments on 9.5% methane/air explosion by gas-liquid two-phase medium.The synergistic inhibition law of gas-liquid two-phase medium on 9.5% methane/air explosion was obtained,and the reason of synergistic effect of explosion suppression was analyzed,and the study proposed the inter phase coupling effect between gas-liquid two-phase medium.Results showed that under the combination of CO2,N2,He and Ar four inert gases and ultra-fine water mist,the inhibition effect on overpressure,flame propagation speed and the maximum flame temperature was obviously improved.When the dilution fraction of four inert gases reached 14% and the amount of ultra-fine water mist reached 8.4 mL(mass concentration 694.4 g/m^3),the gas-liquid two-phase medium had a good inhibition effect on 9.5%methane/air explosion.While the controlling parameters continued to increase,the growth rate of explosion suppression effect gradually reduced.The synergistic explosion suppression effect of CO2 and ultra-fine water mist was the best,N2 was the second,and He and Ar were the least.However,the synergistic explosion suppression level of the combination of He,Ar and ultra-fine water mist had little difference,which provides a scientific support for the clean and efficient development and utilization of inerting water mist explosion inhibition technology.