超临界CO2径向水平井钻井技术应用前景分析

摘要

Supercritical CO2 drilling technology is characterized by low rock-breaking threshold pressure and fast rock-breaking speed.It can effectively control the bottomhole pressure,protect the reservoir and increase the permeability so as to improve the recovery rate.The paper analyzes the feature of the radial horizontal drilling system in micro holes,referring to the characteristics of supercritical CO2,such as reduction of internal pipe friction,pressure injection and smooth movement in the formation It analyzes the feasibility,technological advantage and application prospect of supercritical CO2 micro hole radial horizontal drilling technology.The analysis shows that the technology can make dead wells come back to life,increase oil drainage area,increase single-well oil-gas production and reduce the drilling cost.The technology cannot only improve the drilling speed,but also reduce the jetting pressure needed by rock-breaking.It is an important development orientation for future drilling technology.%超临界CO2钻井技术具有破岩门限压力低和破岩速度快等特点,并能有效控制井底压力、保护储层、提高渗透率,进而提高采收率.通过对微小井眼径向水平井钻井系统特点的分析,结合超临界CO2能够降低管内摩阻、可以注入压力以及在井底超临界CO2状态摩阻下易于在地层内前行等特点,分析了超临界CO2微小井眼径向水平井钻井技术的可行性、技术优势及应用前景.分析结果表明,微小井眼径向水平井钻井技术可使死井复活,能扩大泄油面积,提高单井油气产量,降低钻井成本；超临界CO2微小井眼径向水平井钻井技术不仅可以提高钻井速度,而且能够降低破岩所需的喷射压力,是未来钻井技术重要的发展方向.