油气对瓦斯爆炸的影响

The influence of oil gas on gas explosion

焦坪矿区是我国少有的煤油气共存矿区,曾多次发生重大煤矿安全事故,而油气是造成该地区瓦斯涌出量和爆炸危险性增加的重要原因.关于油气-瓦斯-空气混合气爆炸特性方面的研究并不多,为了考察油气的影响并结合矿区实际情况,选用正己烷作为油气的代表,利用自制的配气系统以及20L爆炸实验装置进行实验.由于已有文献对油气-瓦斯混合气爆炸下限进行了研究,本文重点研究油气对爆炸威力以及瓦斯爆炸上限的影响.实验结果表明正己烷的加入增加了瓦斯的爆炸威力,如当正己烷浓度为2%、甲烷浓度为0.5%时就能发生爆炸并产生0.89MPa的超高压;正己烷浓度为2%时混合气的最大爆炸指数达到9.41MPa·m/s,超过了甲烷最大爆炸指数5.5MPa·m/s.将混合气爆炸上限的理论结果同实验结果进行对比发现二者并不完全符合,理论结果偏安全,而混合气爆炸最佳浓度同化学当量比浓度较为接近.图4,表4,参10.

Jiaoping mining area is a rare mining region in China where oil and gas coexist where the serious safe accidents happen frequently. The oil is main factor which causes out-flow and explosion hazard of gas become serious. But the researches on explosive characteristic of oil -methane-air mixtures are few. Based on the mining reality this article chooses the n-hexane to represent oil gas. The experiments were made using self-made air distribution system and 20 L global explosion installation to investigate the influence of oil gas on gas explosion. The article researched the influence of oil on gas explosion low limits , this article will focus on the influence of oil on explosion power and upper explosive limits. The results show that the n-hexane can increase the explosive power greatly. The mixture which contains 2% n-hexane and 0.5% methane can explode immediately and produces 0.89 MPa high pressure. When n-hexane concentration is 2% the maximum explosion index of mixture can get 9.41 MPa.m.s^-1 which greatly exceeds the methane maximum explosion index 5.5 MPa.m.s^-1. There are some different between the experimental results and theoretical values of upper explosive limit, the theoretical values trend safety. The explosion optimum concentration is close to the stoikiometric ratio.