深层页岩气油基钻井液承压堵漏技术分析
2020-05-21孙云超
孙云超

摘 要:现阶段国内很多地区页岩气朝向深层领域开发,钻井液及固井水泥浆密度均有提升。在生产实践中,为进一步优化固井质量,减少或规避水泥浆流失等问题,增强油基钻井液对井壁承压能力是有效途径。文章概述了国外新型油基堵漏技术的特征及作用机制,在此基础上探究该技术在涪陵页岩气开采中的应用状况。实践表明,该项技术应用期间有效满足了现场施工需要,取得技术经济效果较为理想,具有一定推广价值。
关键词:油基钻井液;页岩气;水平井;技术分析
中图分类号:TE254 文献标志码:A 文章编号:2095-2945(2020)15-0160-02
Abstract: At present, shale gas in many areas of China is developed in deep areas, and the density of drilling fluid and cementing slurry has been increased. In production practice, in order to further optimize cementing quality and reduce or avoid the loss of cement slurry, it is an effective way to enhance the pressure-bearing capacity of oil-based drilling fluid to wellbore. This paper summarizes the characteristics and mechanism of the new oil-based plugging technology abroad, and on this basis, explores the application of this technology in Fuling shale gas production. The practice shows that during the application of this technology, it effectively meets the needs of on-site construction, achieves ideal technical and economic results, and has a certain value of popularization.
Keywords: oil-based drilling fluid; shale gas; horizontal well; technical analysis
既往有大量的生产实践表明,油基钻井液在防塌陷、抗污、热稳定等诸多方面占据优势,在高温深井、页岩气水平井等领域中均有较广泛应用。深层页岩气的储藏埋深三千余米,地层压力系数明显增加,伴隨地层破碎程度的提升,也要求地层承压能力有一定增强。既往有很多学者在研究提升固井质量措施期间,特殊在钻井工作结束后对钻井液实施封堵改造的提议。鉴于此,本文结合前人研究结果,对承压堵漏技术的作用机制及实践应用情况予以探究。
1 国外油基堵漏技术分析
针对过往涪陵页岩气田开采期间存在的漏失状况,通过现场调研后,拟定在本区井段油基钻井液钻进期间,采取防漏堵漏技术手段,要求在存留定向工具的工况下实现堵漏,遵照“小漏随钻堵,大漏高效堵”的原则实施技术,通常能在较短时间内恢复循环。……
