冀中地区深层煤岩气水平井强封堵钻井液技术  

High Plugging Capacity Drilling Fluid Technology for Deep Buried Coal-Bed Methane Drilling in Jizhong Area

作　　者：罗玉财 喻化民 孙昊 于建涛 冯丹 刘飞 LUO Yucai;YU Huamin;SUN Hao;YU Jiantao;FENG Dan;LIU Fei(Exploration Department,PetroChina Huabei Oilfield Company,Renqiu,Hebei 062552;Engineering Technology Research Institute,CNPC Bohai Drilling Engineering Company Limited,Renqiu,Hebei 062552;Downhole Services Company,CNPC Bohai Drilling Engineering Company Limited,Renqiu,Hebei 062552)

机构地区：[1]中国石油集团华北油田分公司勘探事业部,河北任丘062552 [2]中国石油集团渤海钻探工程技术研究院,河北任丘062552 [3]中国石油集团渤海钻探井下作业分公司,河北任丘062552

出　　处：《钻井液与完井液》2025年第2期225-232,共8页Drilling Fluid & Completion Fluid

基　　金：中国石油天然气集团有限公司科技项目“渤海湾及外围盆地风险勘探和目标研究、工程技术攻关及现场试验”(2023YQX10103);中国石油集团渤海钻探工程有限公司科技项目“钻井液微裂缝高效封堵剂的研究”(2023D25F)。

摘　　要：冀中地区深部煤岩气水平井钻探面临可借鉴资料少、地质不确定因素多、煤层薄极易出层、煤层极易垮塌和卡钻风险高等诸多难点与挑战。从深入研究深层煤岩储层特性出发,得出煤系地层井壁失稳由力学因素和理化性能因素双重决定,而提高钻井液封堵性和抑制性是解决该问题的技术关键。在复合盐钻井液基础上用微纳米刚性封堵与柔性可变形封堵相结合形成了深部煤岩地层强封堵钻井液体系配方。室内用滚动回收率、砂床封堵和陶瓷滤芯封堵等实验评价结果显示,其抑制性与封堵性优于KCl聚合物和复合盐钻井液。信探1H井现场应用效果也表明,该钻井液体系中封堵类处理剂配伍性好,对钻井液性能无不良影响,能大幅降低API滤失量,能维护井壁稳定。在现场应用过程中,水平段进尺1270 m,煤层段浸泡23 d未发生井壁失稳现象,振动筛返出岩屑规整正常,仅见少量煤岩掉块,未见泥岩掉块,起下钻过程通畅无阻,无事故与复杂发生,解决了深层煤岩气水平井钻探过程井壁失稳难题,保障了钻井作业顺利进行,该技术的应用有助于深层煤岩气钻探领域实现高效规模开发与突破。Horizontal drilling of deep buried coal-bed methane in Jizhong area has been faced with several difficulties and challenges such as quite limited data for reference,many geologic uncertainties,thin coal-bed layers which are easy to collapse and have difficulties in trajectory control,as well as high risks of pipe sticking etc.Extensive studies on the characteristics of the deep buried coal-bed reservoirs have concluded that the stability of the borehole wall in the coal-bed formations is controlled both by mechanical factors and physio-chemical factors,the key points of technology in solving this problem is to improve the plugging capacity and inhibitive capacity of the drilling fluid.A drilling fluid with high plugging capacity was formulated to drill the coal-bed formations by treating a compounded salt drilling fluid with rigid micro-and nano-plugging agents and deformable plugging agents.Laboratory experiments on the drilling fluid with hot rolling test,sand-bed plugging test and ceramic filter plugging test show that this drilling fluid has inhibitive capacity and plugging capacity better than those of KCl polymer drilling fluids and compounded salt drilling fluids.This drilling fluid has been used in drilling the well Xintan-1H and proved that the plugging agents have good compatibility with other additives and no negative effect on the properties of the drilling fluid.The addition of the plugging agent into the drilling fluid greatly reduced the API filtration rate and effectively maintained the borehole wall stability.In drilling the 1,270 m long horizontal section,the coal-bed formation,after being soaked by the drilling fluid for 23 days,showed no tendency of borehole wall collapse.Cuttings out of hole have regular shapes and sizes,and from the shale shakers only mudstone sloughing was observed.Tripping into the hole and out of hole were both smoothly conducted.The use of this new drilling fluid has effectively solved the borehole wall destabilization problem encountered in deep horizontal coal-bed meth

关 键 词：深层煤岩气 煤岩气水平井 煤系地层 井壁失稳 强封堵钻井液 

分 类 号：TE254[石油与天然气工程—油气井工程]