黄陵一号煤矿中厚煤层110工法瓦斯治理技术研究

Research on gas control technology of 110 construction method in medium thick coal seam of Huangling No.1 Coal Mine

切顶留巷无煤柱开采下煤与瓦斯共采是我国无煤柱开采技术的重要发展方向,为解决陕西黄陵一号煤矿中厚煤层110工法开采工艺条件下卸压瓦斯治理难题,采用理论分析与数值模拟相结合的研究方法,分析了切顶留巷开采导致覆岩结构变化及裂隙分布特征。结果表明,根据110工法开采过程顶板结构状态变化特征,将切顶留巷围岩结构运动划分为4个阶段。工作面充分采动后,垮落带的高度基本不再变化,稳定在7 m左右,裂隙带发育高度为55 m左右,应力集中系数约为2.73,采空区中部垮落带内裂隙基本处于压实闭合状态,裂隙区宽度约为40 m,切眼处岩层破断角为67°,工作面停采处岩层破断角约为62°。根据1009工作面切顶留巷无煤柱开采技术下裂隙分布特征,施工定向高位试验钻孔,现场抽采效果良好,有效治理了1009回风巷瓦斯浓度超限问题,实现了1009工作面安全回采。

The co-mining of coal and gas under non-pillar mining of roof-cutting entry retaining is an important development direction of non-pillar mining technology in China.In order to solve the problem of pressure-relief gas control under the condition of 110 mining method in medium-thick coal seam of Huangling No.1 Coal Mine in Shaanxi Province,the combination of theoretical analysis and numerical simulation was used to analyze the change of overburden structure and fracture distribution caused by roof-cutting entry retaining.The results show that according to the change characteristics of roof structure state in the mining process of 110 method,the structure movement of surrounding rock in roof cutting and retaining roadway is divided into four stages.After the working face is fully mined,the height of the caving zone is basically no longer changed,and it is stable at about 7 m.The development height of the fracture zone is about 55 m,and the stress concentration coefficient is about 2.73.The fractures in the caving zone in the middle of the goaf are basically in a state of compaction and closure.The width of the fracture zone is about 40 m,the fracture angle of the rock stratum at the open-off cut is 67°,and the fracture angle of the rock stratum at the stop of the working face is about 62°.According to the fracture distribution characteristics under the non-pillar mining technology of the 1009 working face,the directional high-level test borehole was constructed,and the on-site extraction effect was good.The problem of gas concentration overrun in the 1009 return airway was effectively controlled,and the safe mining of the 1009 working face was realized.