后高抽立眼治理初采期瓦斯的CFD模拟研究

CFD Simulation Study on Treating Gas in Early Stage of Gas Production by Post-high Drainage Vertical Holes

针对后伪高抽巷施工难度大、成本高的问题,提出了以后高抽立眼代替后伪高抽巷的初采期瓦斯治理方案。为优化后高抽立眼布置参数,以新大地煤矿15201工作面为原型建立了数值计算模型并进行了数值模拟。获得了新大地煤矿15201工作面后高抽立眼的合理布置参数,即:后高抽立眼距离切眼煤壁的距离为10 m,与回风巷之间的距离为10 m。为考察初采期后高抽立眼的瓦斯抽采效果,对走向高抽巷抽采管路的瓦斯混合流量及瓦斯浓度进行了现场实测,实测结果表明,在工作面初次来压期间,后高抽立眼瓦斯抽采量急剧增大,在初采期就取得了较好的瓦斯抽采效果,解决了15201工作面初采期瓦斯超限问题。

In order to solve the problem of high difficulty and high cost in the construction of post-false high drainage roadway, a new gas control scheme is proposed to replace the post-false high drainage roadway with post-high vertical drainage hole. In order to optimize the parameters of post-high vertical drainage hole, a numerical model was established based on 15201 working face of Xindadi Coal Mine, and the numerical simulation was carried out. The reasonable layout parameters of the post-high vertical drainage hole of 15201 working face of Xindadi Coal Mine were obtained, i.e., the distance between the vertical drainage hole and the cutting hole coal wall was 10 m, and the distance between the vertical drainage hole and the return airway was 10 m. In order to investigate the gas extraction effect of post-high vertical drainage hole after the initial mining period, we carried out field measurement of gas mixture flow and gas concentration in the drainage pipeline of high drainage roadway. The measured results show that during the initial pressure of the working face, the amount of gas extraction increased sharply in the post-high drainage hole, and a good gas extraction effect was achieved in the initial production period, which solved the problem of gas over-limit in the initial production period of 15201 working face.