空气反循环钻探技术在超高海拔地区的应用

Application of air reverse circulation drilling technology in ultra⁃high altitude area

空气反循环钻探与传统的钻探工艺相比,具有成本低、钻速快、场地要求低、样品可靠无污染等优点。因其以压缩空气为主要循环介质,遇水、冰容易造成淤堵,应用于超高海拔地区空气稀薄、永冻层较厚、地下水丰富等复杂环境一直以来都是难题。为验证空气反循环钻探工艺应用于超高海拔复杂环境的可行性,本文依托西藏巨龙铜矿空气反循环钻探项目,通过选取高功率设备、防水工艺改进以及防冻材料应用等多项举措,成功研究出克服复杂环境因素的整套施工工艺,使其综合效率与平原地区相近,证明了空气反循环钻探技术可以应用于超高海拔地区。

Compared with the traditional drilling technology,air reverse circulation drilling has the advantages of low cost,fast drilling speed,low site requirements,reliable and non‑pollution samples.Because it takes compressed air as the main circulating medium,it is easy to cause blockage when meets water and ice.Therefore,it has been a difficult problem to be applied in the ultra‑high altitude area with complex environment such as thin air,thick permafrost and abundant groundwater.In order to verify the feasibility of air reverse circulation drilling technology applied in the complex environment,based on the air reverse circulation drilling project of Julong copper mine in the Tibet autonomous region,this paper has successfully developed a complete set of construction technology to overcome complex environmental factors through the selection of high‑power equipment,the improvement of waterproof technology and the application of anti‑freezing materials.As a result,its comprehensive efficiency is similar to that of the plain area,and the air reverse circulation drilling technology can be applied to the ultra‑high altitude area is proved.