四川长宁页岩气长水平段油基钻井液井壁稳定技术  

Wellbore Stabilization Technology of Oil-based Drilling Fluid in Long Horizontal Section of Shale Gas in Changning Block,Sichuan Basin

作　　者：白杨 翟玉芬 罗平亚 代锋 吴凌风 罗玉婧 BAI Yang;ZHAI Yufen;LUO Pingya;DAI Feng;WU Lingfeng;LUO Yujing(School of Oil&Natural Gas Engineering,Southwest Petroleum University,Chengdu Sichuan 610500,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China;Geological Engineering Department of Sichuan Changning Natural Gas Development Co.,Ltd.,Chengdu,Sichuan 610000,China;National Engineering Research Center of Oil&Gas Drilling and Completion Technology,Beijing 102200,China;Sinopec Chongqing Fuling Shale Gas Exploration&Development Co.,Ltd.,Fuling,Chongqing 408014,China)

机构地区：[1]西南石油大学石油与天然气工程学院 [2]西南石油大学油气藏地质及开发工程国家重点实验室 [3]四川长宁天然气开发有限责任公司地质工程部 [4]油气钻完井技术国家工程研究中心 [5]中国石化重庆涪陵页岩气勘探开发有限公司

出　　处：《钻采工艺》2024年第6期152-158,共7页Drilling & Production Technology

基　　金：国家自然基金项目“深井、超深井水基钻井液失水造壁性与流变性调控机理研究”(编号:52274008);国家重点研发计划课题“井筒稳定性闭环响应机制与智能调控方法”(编号:2019YFA0708303);国家自然科学基金联合基金项目“深层页岩气水平井井壁岩石结构强化及调控机理研究”(编号:U23A2026)。

摘　　要：四川盆地长宁区块页岩气储层已经进入纵向立体开发阶段,在钻进龙马溪组龙一1^(4)小层长水平段过程中井壁垮塌、卡钻等复杂事故频发。为此,基于X射线衍射、扫描电镜明确了龙一1^(4)小层岩样矿物组成及微观结构特征,揭示了该区块井壁失稳机理,采用石墨烯纳米片和多级微米刚性封堵剂对现场钻井液进行封堵性能优化,通过提高油水比和氯化钙(CaCl_(2))溶液浓度增强钻井液抑制性,形成了一套强封堵强抑制防塌钻井液体系。现场应用中未出现由于掉块导致的憋泵、憋顶驱、卡钻等复杂事故,摩阻系数均处于中、低值区间,水平段平均井径扩大率为4.07%。说明该油基钻井液能够有效强化井壁,且具有降摩减阻效果,能够解决长宁区块龙马溪组页岩水平井井眼失稳问题。The shale gas reservoir in Changning block of Sichuan Basin has entered the vertical and three dimensional development stage,and complex accidents such as wall collapse and pipe sticking occurred frequently in Longyi 1^(4)Sub-bed,Longmaxi Formation,Changning Block.Therefore,based on X-ray diffraction and scanning electron microscopy,the mineral composition and microstructure characteristics of the Longyi 1^(4)small layer rock sample were determined,and the mechanism of wellbore instability in this block was revealed.Graphene nanosheets and multistage micron rigid plugging agents were used to optimize the plugging performance of the drilling fluid in the field,and the inhibition of drilling fluid was enhanced by increasing the oil-water ratio and CaCl_(2)solution concentration.Finally,a strong plugging and strong inhibition anti-collapsing drilling fluid system was established.After the drilling fluid system was applied in the field,there were no complex accidents such as frequent pump pressure increase,top drive clogging and sticking caused by falling blocks.All the friction coefficients were in the medium to low value range,and the average borehole diameter expansion rate in the horizontal section was 4.07%.It shows that the oil-based drilling fluid can effectively strengthen the borehole and reduce friction and drag,and can solve the borehole instability problem of Longmaxi formation shale horizontal well in Changning block.

关 键 词：页岩气 井壁稳定 油基钻井液 微纳米封堵 水平井 

分 类 号：TE254[石油与天然气工程—油气井工程]