顶板来压规律对高位钻孔瓦斯抽采浓度的影响及优化

通过现场实测、理论分析及Fluent数值模拟等方法,研究了新疆某矿12B801综放工作面支架工作阻力及高位钻孔瓦斯抽采浓度变化,结果表明：顶板来压呈现大、小周期变化规律,大周期平均来压步距约65.0m,小周期平均来压步距约15.5m,大、小周期来压直接影响着高位钻孔瓦斯抽采浓度；利用大、小周期来压规律,对原设计抽采钻孔参数进行了优化,Fluent模拟表明钻孔优化后可将工作面上隅角瓦斯浓度比原方案降低45%以上,现场实测综放工作面上隅角瓦斯最大浓度仅为0.24%,证明抽采钻孔优化的合理性。

Influence of roof pressure law on gas drainage concentration in high level boreholes and its optimization

Through field measurement, theoretical analysis and Fluent numerical simulation, the working resistance of the support of the 12B801 fully mechanized coal caving face and the change of gas extraction concentration in the high level hole in a Xinjiang mine are studied. The results show that the pressure of the top plate presents a large and small periodic change law, the large period average pressure step distance is about 65.0m, the small period average pressure step distance is about 15.5m, the large and small period pressure directly affects the gas extraction concentration in the high borehole. Using the law of large and small cycle pressure, the parameters of the original design are optimized, and the Fluent simulation shows that the gas concentration in the upper corner of the working face can be reduced by more than 45% after the drilling optimization is optimized. The maximum gas concentration in the upper corner of the working face is only 0.24%, which proves that the optimization of the extraction drilling is reasonable.