Mining and Design Branch,China Coal Research Institute Department of Mining and Design,Tiandi Science and
Technology Company Limited China Coal Research Institute Jalainur Coal Industry Company Limited

针对灵泉矿巨厚煤层下分层综放开采时,上分层泄水巷中的瓦斯极易进入下分层上平巷内的问题,采用从下分层上平巷向泄水巷中打钻孔注氮置换瓦斯的技术措施,通过CFD数值模拟了上分层泄水巷及采空区内的瓦斯运移规律,求出了合理的注氮参数,分析了不同注氮速率、注氮间距时泄水巷内瓦斯浓度的变化。结果表明:注氮参数变化时,瓦斯在泄水巷内的分布规律存在差异性;当钻孔间距为30 m、注氮量为800 m3/h时,置换瓦斯的效果最佳。最终将合理的注氮参数应用于工业现场,下分层开采时不再出现瓦斯超限的现象。

When a fully-mechanized upper slice mining was conducted in the bottom slice of the extreme thick seam in Lingquan Mine, according to the problem occ urred that the gas in the water drainage gateway of the upper slice was easily run into the up gateway of the bottom slice.A borehole drilling was conducted from the up gateway in the bottom slice to the water drainage gateway in the top slice in order to make the nitrogen injection to replace the gas.CFD numerical value was applied to simulate the migration law of gas in the water drainage gateway in the upper slice and the goaf.In order to have the rational nitrogen injection parameters,the variation of gas concentration in the water drainage gateway with different nitrogen injection rate and the nitrogen injection spacing was analyzed.The results showed that when t he parameters of the nitrogen injection varied,the distribution law of gas in the water drainage gateway would have differences.When the borehole space was 30 m and the nitrogen injection amount was 800 m~3/h,the replaced gas effect was best.Finally,the rational nitrogen injection parameters should be applied to the industrial site a nd the results showed that in the bottom slice mining,there was no gas over limit phenomenon occurred.

国家自然科学基金青年基金资助项目(51504135)；煤炭科学研究总院科技创新基金资助项目(2015ZYJ001)；中国煤炭科工集团公司科技创新基金资助项目(2014MS034)；