沁水盆地煤层气二开水平井钻井关键技术  

Key technologies of second-spud horizontal-well drilling used for CBM in Qinshui Basin

作　　者：贾佳 谭章龙 王鹏[2] 林俊文 申文杰 曹超[2] 杨琦[2] JIA Jia;TAN Zhanglong;WANG Peng;LIN Junwen;SHEN Wenjie;CAO Chao;YANG Qi(CNOOC EnerTech-Drilling&Production Co.,Tianjin 300452,China;China United Coalbed Methane Co.Ltd.,Taiyuan,Shanxi 030000,China)

机构地区：[1]中海油能源发展股份有限公司工程技术分公司,天津300452 [2]中联煤层气有限责任公司,山西太原030000

出　　处：《天然气技术与经济》2023年第4期34-39,50,共7页Natural Gas Technology and Economy

基　　金：中海油七年行动计划子课题“煤层气水平井二开井身结构配套技术服务”(HX20220089)。

摘　　要：为了解决沁水盆地煤层气开发过程中优质储层钻遇率低、固井质量差、储层保护难度大等问题,以提高煤层气的后期压裂和产气效果为研究对象,开展了井眼轨迹优化设计、井身结构和配套工艺、钻井液、二开半程固井等一系列技术研究。研究结果表明:①轨迹设计采用“双增双稳”剖面,设置控制点可精确控制轨迹走向;②三开水平井优化为二开大井眼水平井(Ф311.2 mm×Ф244.5 mm+Ф215.9 mm×Ф139.7 mm);③采用可降解聚膜钻井液可有效保护储层;④使用打捞式免钻塞完井工具,完成二开半程固井,可避免煤层固井漏失;⑤形成了适合沁水盆地的煤层气二开水平井钻井关键技术体系。现场应用结果表明可以缩短钻井周期30%,提速20%以上,有效提高煤层气整体开发效益。结论认为,煤层气二开水平井钻井关键技术可以为后续煤层气开发提供借鉴和参考。There exist many problems during coalbed methane(CBM)development in Qinshui Basin,such as low drilling rate,poor cementing quality and troublesome reservoir protection.Thus,some drilling technologies were studied from as⁃pects of optimization of wellbore trajectory,wellbore structure and supporting process,drilling fluid,and third-spur half ce⁃menting in order to improve both fracturing and production effects.Results show that(i)the profile of"double increase and double stability"is employed in trajectory design,and trajectory direction is governed precisely by setting control points;(ii)a third-spud horizontal well can be optimized to the second-spud horizontal well with large borehole(Ф311.2 mm×Ф244.5 mm+Ф215.9 mm×Ф139.7 mm);(iii)a kind of drilling fluid to degrade polymer film is adopted for reservoir protec⁃tion with effect;(iv)the fishing-type completion tool without plug drilling is used for half cementing in the second spud⁃ding so as to avoid lost circulation during cementing;and(v)the key drilling technologies are suitable for CBM secondspud horizontal wells in Qinshui Basin.In addition,after field application,it is revealed that the drilling period is short⁃ened by 30%and the ROP is improved by over 20%,indicating an overall increase in CBM development benefits.In con⁃clusion,these technologies can provide reference for subsequent CBM development.

关 键 词：沁水盆地 煤层气 水平井 固井 效益 

分 类 号：TE243[石油与天然气工程—油气井工程]