惰性气体对KHCO3冷气溶胶甲烷抑爆性能的影响研究

主动式喷粉抑爆装置是煤矿甲烷爆炸的防控装备之一,该装置装填的超细粉体抑爆剂可在甲烷爆炸初期主动喷洒,使其中超细粉体颗粒形成冷气溶胶,减少后续甲烷爆炸危害。为进一步提升主动式喷粉抑爆装置的抑爆性能,探究冷气溶胶抑爆剂的抑爆规律,使用5 L爆炸管道系统,测试了N₂和CO₂两种惰性气体对KHCO₃冷气溶胶甲烷抑爆性能的影响。试验结果表明:N2、CO₂显著强化了KHCO₃冷气溶胶对9.5%甲烷/空气预混气的抑制性能,相比于空气驱动的KHCO₃冷气溶胶,气体介质中含有惰性气体的KHCO₃冷气溶胶使甲烷爆炸最大压力下降更为显著,到达峰值压力时间也更长;CO2对KHCO₃冷气溶胶抑爆性能的增效作用强于N2。其中,体积分数0.03 g/L的KHCO₃冷气溶胶仅使甲烷最大爆炸压力降低60.4%,而在气体介质内充入体积分数15%~20%的N2或5%~10%的CO2时,同浓度KHCO₃冷气溶胶可以完全抑制甲烷爆炸,继续增加惰性气体的体积分数可以进一步减少KHCO₃冷气溶胶用量,从而降低主动式喷粉抑爆装置的成本。试验考察了在不同浓度KHCO₃冷气溶胶与不同体积分数N2、CO2作用下的甲烷爆炸情况,得到了KHCO₃冷气溶胶与惰性气体的最佳抑爆用量配比,能够为基于KHCO₃冷气溶胶的主动式喷粉抑爆装置的设计提供理论依据及技术参数。此外,讨论了含惰性气体的KHCO₃冷气溶胶系统的甲烷抑爆机理,并分析了惰性气体的增效原因。

Research on synergistic effect of inert gas on methane explosion suppression performance of KHCO3 cold aerosol

Active powder spraying and explosion suppression device is one of the prevention and control equipment for methane explosion in coal mines.It can be actively sprayed at the initial stage of methane explosion after being filled with ultra-fine powder explosion suppres?sant,so that ultra-fine powder particles form cold aerosols and reduce the hazards of subsequent methane explosion.In order to further im?prove the explosion suppression performance of the active explosion suppression device,and to explore the explosion suppression law of cold aerosol explosion suppression agents,the methane explosion suppression characteristics of KHCO₃cold aerosol driven by inert gas was tested using a 5 L explosion tube system.The experimental results showed that N2 and CO₂ significantly enhance the suppression perform?ance of KHCO₃cold aerosol on 9.5%methane/air premixed gas explosion,which revealed lower max-pressure and longer time to maxpressure on methane explosion compared with the suppression by KHCO₃cold aerosol driven by air.Among them,0.03 g/L KHCO₃cold aerosol reduced the max-pressure of methane explosion by 60.4%,but when the gas medium is filled with 15%~20%N2 or 5%~10%CO2,the same concentration of KHCO₃cold aerosol can completely suppress the explosion of methane.As the volume fraction of inert gas increased,the amount of KHCO₃cold aerosol was further reduced,thereby reducing the cost of active explosion suppression device.The experiment investigated the explosion of methane under the action of different concentrations of KHCO₃cold aerosols and different volume fractions of N₂ and CO₂,and obtained the optimal combination ratio of KHCO₃cold aerosols and inert gases,which can provide theoretical basis and technical parameters for the design of active explosion suppression system based on KHCO₃cold aerosol.In addition,the meth?ane suppression mechanism of the KHCO₃cold aerosol system containing inert gas was discussed,and the reason for the synergistic effect of inert gas was analyzed.