微裂缝发育泥页岩地层井壁稳定技术研究与应用  

Study and Application of Borehole Stabilization Technology in Shale Strata Containing Micro-Fractures

作　　者：于雷 张敬辉 刘宝锋 孙荣华 季一冰 刘传清 

机构地区：[1]中石化胜利石油工程有限公司钻井工艺研究院,山东东营257000 [2]中石化新疆新春石油开发有限责任公司,新疆克拉玛依834000 [3]中石化胜利石油工程有限公司海洋钻井公司,山东东营257055

出　　处：《石油钻探技术》2017年第3期27-31,共5页Petroleum Drilling Techniques

基　　金：国家科技重大专项"页岩气等非常规油气开发环境检测与保护关键技术"课题五"致密油气开发环境保护技术集成及关键装备"(编号:2016ZX05040-005);中国石化集团公司科技攻关项目"低活度水基钻井液体系研究"(编号:JP15015)部分研究内容

摘　　要：泥页岩微裂缝发育,微裂缝宽窄不等,形状多变不规则,导致钻井过程中泥页岩地层易出现井壁失稳问题,为此,提出了全固相粒度优化+多元协同封堵技术,通过对钻井液自身的固相粒度及需添加的暂堵剂的粒度进行优化,并对胶乳沥青、纳米乳液和铝基聚合物等3种封堵材料进行复配,以期达到多元协同封堵泥页岩微裂缝的目的。室内试验结果表明,粒度优化后的钻井液API滤失量由4.8mL降为3.2mL,高温高压滤饼的抗剪切强度系数为0.74,岩心动滤失量显著降低。全固相粒度优化+多元协同封堵技术在渤海某油田和胜利油田多口井进行了现场应用,优化后的微裂缝封堵钻井液高温高压滤失量显著降低,成功钻穿大段含油泥页岩,未发生井下故障。室内试验与现场应用结果表明,全固相粒度优化+多元协同封堵技术能显著提高泥页岩地层的井壁稳定性,为同类型地层水平井的安全快速钻进提供技术借鉴。Highly variable micro-fractures that demonstrate differing widths and irregular shapes are u- niversally present in shale,so the borehole is easily subjected to instability. To solve this problem, a tech- nology that combines the optimization of solid particle size and multiple collaborative plugging was proposed. In the study, the solid particle-size of drilling fluid itself and the particle size of the temporary blocking agent were optimized, three plugging materials（i, e. ,latex asphalt, nanoemulsion and aluminum poly- mer） were combined, and consequently multiple collaborative plugging of micro-fractures in shale was achieved. Grain-size distribution optimization, filter cake shear strength coefficient and HTHP dynamic filtration experiments were carried out. The results showed that API filtration of drilling fluid decreased from 4. 8 mL to 3.2 mL,the shear strength coefficient of HTHP filter cake was 0. 74, and the dynamic filtration of the rock sample declined significantly. The technology of all solid particle size optimization combined with multiple collaborative plugging was applied successfully at many wells in Bohai Bay Oilfield and Shen- gli Oilfield. The HTHP filtration of optimized micro-fracture plugging drilling fluids significantly declinedand a long section of oil shale was penetrated without downhole failures. Laboratory tests and field applications showed that the technology of all solid particle size optimization combined with multiple collaborative plugging could significantly enhance borehole stability in shale formations and maybe used as the tech- nological reference for the safe and quick drilling of horizontal wells in same type of formation.

关 键 词：泥页岩 微裂缝 井眼稳定 多元协同 封堵 粒度分布 

分 类 号：TE254[石油与天然气工程—油气井工程]