温度与CO气体耦合作用对瓦斯爆炸界限影响实验

Experimental Study on the Coupling Influence of Temperature and CO Concentration on CH4 Explosion Limit

针对煤矿火区封闭过程中常发生的瓦斯爆炸问题,运用 20 L 爆炸装置,实验研究了不同环境温度(25~200 ℃)和 CO 浓度(1%~10%,体积分数)条件下瓦斯的爆炸极限和最大爆炸压力。结果表明:单因素可燃性气体 CO 体积分数升高,瓦斯爆炸上限、下限均下降,爆炸极限范围变宽;温度升高,爆炸上限升高,下限下降;常压条件下,随着温度升高,爆炸上限与初始温度呈二次函数关系变化,爆炸下限与初始温度呈对数关系变化;瓦斯爆炸上限与下限爆炸压力随着初始温度升高均降低,随着 CO 体积分数升高均升高。多因素高温与 CO 气体耦合作用下,瓦斯爆炸上限升高,下限下降,瓦斯爆炸危险性增加;初始温度和 CO气体对爆炸极限的耦合影响比单一因素的影响大,对爆炸上限的影响更为显著。

Gas explosion often occurs in the course of closing fired coal mine. The explosion limit and maximum explosion pressure under temperatures ranging from 25 ℃ to 200 ℃ and CO volume fractions of 1% 10% are studied by using a special 20 L explosive device. The results show that upper and lower explosion limits all decrease with increasing CO volume fraction, the range of explosion limit is widened in the presence of only CO. The upper gas explosive limit increases while its lower limit decreases as temperature increases. At ambient pressure, the upper gas explosive limit increases quadratically with initial temperature while the lower limit increases logarithmically with initial temperature. Increasing CO volume fraction results in increase in both the upper pressure limit and the lower pressure limit. Coupling CO gas with high temperature, the gas explosive upper limit increases and the lower limit decreases thus higher risk is expected in such condition. Explosive limits, especially the upper limit are more sensitive to coupling factors than to single factor.