Qiao Zhenglong, Miao Qianfei, Ma Heng, Xu Liang, Li Rong, Gao Jie
College of Resource and Environment Engineering, Jilin Institute of Chemical Technology, Jilin, Jilin 132022, China.
College of Safety Science and Engineering, Liaoning Technical University, Huludao, Liaoning 125105, China.
ACS Omega. 2024 Dec 25;10(1):769-784. doi: 10.1021/acsomega.4c07713. eCollection 2025 Jan 14.
The inhibition of methane-air explosions by air jet-driven NaHCO powders and porous barriers was investigated in this study. Flame images and overpressure data were recorded using high-speed cameras and pressure sensors. The inhibition mechanism of NaHCO powder was further investigated using the reaction mechanism of sodium-containing substances and methane combustion. The results showed that NaHCO powder driven by high-pressure gas jets reduces the average propagation speed of flame fronts and the rising rate of overpressure. The presence of porous barriers increases the turbulence intensity in the pipe and the travel time of the NaHCO particles. Thus, the contact time between the large particle powder and the flame increases, and the inhibiting effect on flame propagation gradually increases as the obstruction rate increases. NaHCO powder inhibits methane-air explosions through physical and chemical mechanisms. From a chemical perspective, sodium-containing radicals preferentially react with CO in the system to form CO, reducing the production of H* and OH* radicals in the reaction system. The cycle of gaseous Na and NaOH also consumes H* and OH* radicals in the system, blocking the chain reaction.
本研究考察了空气喷射驱动的NaHCO粉末和多孔屏障对甲烷-空气爆炸的抑制作用。使用高速摄像机和压力传感器记录火焰图像和超压数据。利用含钠物质与甲烷燃烧的反应机理，进一步研究了NaHCO粉末的抑制机理。结果表明，高压气体喷射驱动的NaHCO粉末降低了火焰前沿的平均传播速度和超压上升速率。多孔屏障的存在增加了管道内的湍流强度和NaHCO颗粒的停留时间。因此，大颗粒粉末与火焰的接触时间增加，随着阻塞率的增加，对火焰传播的抑制作用逐渐增强。NaHCO粉末通过物理和化学机制抑制甲烷-空气爆炸。从化学角度来看，含钠自由基优先与体系中的CO反应生成CO，减少了反应体系中H和OH自由基的产生。气态Na和NaOH的循环也消耗了体系中的H和OH自由基，阻断了链式反应。
