防控采煤工作面瓦斯燃烧新技术实验研究

Experimental study of new technology for preventing gas combustion in mining face

在分析井下瓦斯燃烧起因和特点的基础上,结合目前煤矿多发的瓦斯燃烧事故,建立超细水雾作用下采煤工作面瓦斯燃烧防控实验平台。在不同条件下进行系列超细水雾抑制瓦斯燃烧实验,以甲烷流量150 mL/min、其体积分数90%、超细水雾流量220 mL/min、水雾粒径5～30μm为最佳实验工况进行水雾与瓦斯燃烧作用机理研究。结果表明:超细水雾与瓦斯火焰作用后,在火焰周围形成封闭水雾圈,瓦斯燃烧火焰出现被抑制—切割—再抑制—再切割的过程,使火焰由大变小,直至熄灭;与自由燃烧相比,火焰周围温度和氧气体积分数均出现不同程度的降低,整个熄灭过程仅用90 s。

Based on analyzing the reasons and characteristics of gas combustion under coal mine and integrating the situation of gas combustion accident which frequently occured at present, the authors built the experimental platform with the ultra fine water mist to prevent gas combustion. A series of experiments with the ultra fine water mist to pre- vent gas combustion was conducted. Finally, the best operation parameter to study the water mist restrained gas com- bustion was obtained with the methane flow of 150 mL/min, the methane concentration of 90%, the atomization quanti- ty of 220 mL/min, and the water spray particle size of 5-30 μm. The results show that after release ultra fine water mist, a closed spray ring is formed around the gas flame, and the gas flame interact with ultra fine water mist appears the process of restrained-cut flame-restrained again-cut flame again, with the gas flame gradual becoming smaller until to extinguish. Comparing with free combustion, the temperature and oxygen concentration around gas flame all reduced with different degree, and the whole process of flame extinguish is only 90 s.