九里山矿底板岩巷施钻瓦斯涌出规律研究

Study on gas emission law of bottom slate roadway drilling in Jiulishan Mine

以焦作矿区九里山矿为例,通过实测堆煤瓦斯涌出量及钻孔下风侧距离钻孔不同距离断面上的瓦斯体积分数,研究底板岩巷施钻期间瓦斯涌出来源、涌出量及其变化规律。结果表明:堆煤瓦斯释放量相对较低,通过正常通风不会导致瓦斯体积分数超限;正常施钻期间,钻孔瓦斯涌出量相对较高,距钻孔不同距离,瓦斯体积分数不断变化,整体呈现出逐渐降低的趋势,但在距离钻孔下风侧2 m的位置上,仍然可能导致瓦斯体积分数超限。

In order to find out the main sources of gas emission during drilling and clarify its change law,this paper takes Jiulishan Mine in Jiaozuo Mining Area as an example,and expounds the source,emission and variation law of gas emission during the drilling of floor rock roadway by measuring the amount of gas emission from coal pile and the gas concentration with different distances from the borehole to the windward side of the borehole.The results show that the amount of gas released from the coal stockpile is relatively low,and the gas volume fraction will not exceed the limit through normal ventilation.During normal drilling,the gas emission from the borehole is relatively high,and the gas concentration changes continuously at different distances from the borehole,and the overall trend is gradually decreasing.However,the gas concentration may still exceed the limit at the position 2 m away from the downwind side of the borehole.