残煤复采掘进工作面揭露空巷时瓦斯分布研究

Research on Gas Distribution for Exposed Empty Lane at Heading Face as Residual Coal Repeated Mining

旧采空巷经过长时间的时间演化,空巷内会存在一定浓度和压力的瓦斯,在复采掘进巷道揭露空巷时,一定浓度和压力的瓦斯肯定会涌出。以圣华煤业掘进的1202巷为研究背景,采用流体力学软件Fluent模拟掘进巷道揭露空巷时工作面及空巷中的瓦斯浓度变化及分布情况。模拟结果表明:掘进工作面瓦斯浓度先是迅速升高,然后迅速下降,3 min左右下降到1%以下,随着通风时间加长,瓦斯浓度接近于0;空巷内两端瓦斯浓度迅速下降,3 min左右下降到1%以下,随着通风时间加长,瓦斯浓度也接近于0。

After a long time evolution,there will be gas in the old empty lane with a certain concentration and pressure. The gas emission will happen when exposing empty lane in the process of residual coal repeated mining of heading face. 1202 heading face is taken as research background in Shenghua Coal Industry. Through the fluid dynamics software Fluent,gas concentration variation and distribution law is simulated in working face and empty lane when empty lane is exposed for roadway excavation. The results show that the gas concentration increases rapidly in heading face at first,then decreases rapidly,it decreases under 1% about 3 min later,with the ventilation time lengthened,the gas concentration is close to zero. At the same time,the gas concentration in two ends of empty lane increases rapidly firstly,then decreases rapidly,it decreases under 1% about 3 min later,as the ventilation time going,the gas concentration is close to zero too.