远距离下保护层采动卸压及地面井失稳变形研究

发布时间：2018-05-14 06:39

本文选题：远程采动煤岩体 + 下保护层　；参考：《中国矿业大学》2015年硕士论文

【摘要】：作为高瓦斯复杂煤层群开采的典型代表,淮南矿区在煤层群集约化开发及煤与瓦斯共采领域取得较大成功,卸压煤层瓦斯地面井抽采也在部分矿井取得成功。本文以地面井采气成功率高的丁集矿及试验井成功率相对较低的顾桥矿为研究对象,采用理论分析、数值实验与工程实践相结合的方法,研究远距离下保护层采动煤岩体卸压变形移位规律、地面井的稳定性分析与特种加固措施以及卸压煤层瓦斯地面井和井下组成的立体抽采工程实践。应用FLAC3D软件,模拟分析了远距离下保护层11-2煤层采动造成的覆岩卸压及变形移位规律、被保护层13-1煤层卸压及变形移位规律及被保护层渗透性演化规律;模拟分析了地面井套管失稳变形的挤压破坏和剪切破坏两种响应机制,将煤层采面走向上看作半无限大平面问题,建立沿煤层倾向的模型,模拟了在采动过程中不同位置处预设地面井的变形移位规律,揭示出钻井在采动影响下的破坏特征,合理选择地面钻井的位置,采用“G”级油井水泥固井来防止套管破断。研究对象现场工程实践表明,顾桥矿、丁集矿采用的地面钻井、井下工作面高抽巷和走向钻孔、采空区埋管、顺层钻孔和底抽巷穿层钻孔及顺槽穿层钻孔等立体式抽采瓦斯与方法,使工作面瓦斯抽采率达到47.8~87.5%。提出了淮南矿区地面钻井瓦斯抽采效果评价方法,得出丁集矿地面井是成功的,而顾桥矿地面井失败,建议顾桥矿采用丁集矿试验成功的“G”级油井水泥固井方法来提高地面钻井井身稳定性。
[Abstract]:As a typical representative of high gas complex coal seam mining, Huainan mining area has achieved great success in the field of intensive development of coal seam group and comining of coal and gas. In this paper, the Dingji ore with high gas production success rate in surface wells and Guqiao mine with relatively low success rate in test wells are taken as the research objects. The method of combining theoretical analysis, numerical experiment and engineering practice is adopted in this paper. This paper studies the displacement law of pressure relief deformation of coal and rock mass in the mining of protected strata at a long distance, the stability analysis of surface wells and special reinforcement measures, and the practice of three-dimensional drainage engineering composed of surface and underground gas wells in relief coal seams. FLAC3D software is used to simulate and analyze the overburden pressure relief and deformation displacement caused by mining of protective layer 11-2 coal seam at a long distance, the pressure relief and deformation displacement law of protected layer 13-1 seam and the evolution law of permeability of protected layer. In this paper, two response mechanisms of casing instability deformation in surface wells are simulated and analyzed, such as extrusion failure and shear failure. The upward strike of coal seam face is regarded as a semi-infinite plane problem, and a model of coal seam inclination is established. The deformation and displacement law of preset ground wells at different positions in the course of production is simulated, the failure characteristics of drilling under the influence of production are revealed, the location of surface drilling is reasonably selected, and the cementing of "G" grade oil well cement is adopted to prevent casing breaking. The field engineering practice shows that the surface drilling used in Guqiao Mine and Ding Ji Mine, the high pumping roadway and directional drilling hole in underground working face, the buried pipe in goaf, The gas extraction rate of the working face is 47.8% and 87.5% through the three dimensional gas extraction methods, such as drilling along the bedding and bottom drainage roadway, and drilling through the trench in the same way. A method for evaluating the effect of gas drainage in Huainan mining area is put forward. It is concluded that the surface well of Ding Ji Mine is successful, but the ground well of Guqiao Mine has failed. It is suggested that the cementing method of "G" grade oil well cement, which was successfully tested by Ding Ji ore deposit, be used to improve the wellbore stability of surface drilling in Guqiao Mine.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD712.6

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