裂缝封堵层形成机理及堵漏颗粒优选规则  

Formation mechanisms of fracture plugging zone and optimization of plugging particles

作　　者：雷少飞 孙金声 白英睿[1] 吕开河[1] 张曙沛 许成元 程荣超 刘凡 LEI Shaofei;SUN Jinsheng;BAI Yingrui;LYU Kaihe;ZHANG Shupei;XU Chengyuan;CHENG Rongchao;LIU Fan(School of Petroleum Engineering,China University of Petroleum,Shandong Qingdao 266580,China;CNPC Engineering Technology R&D Company Limited,Beijing 102206,China;Petroleum Engineering School,Southwest Petroleum University,Chengdu 610500,China)

机构地区：[1]中国石油大学(华东)石油工程学院,山东青岛266580 [2]中国石油集团工程技术研究院有限公司,北京102206 [3]西南石油大学石油与天然气工程学院,成都610500

出　　处：《石油勘探与开发》2022年第3期597-604,共8页Petroleum Exploration and Development

基　　金：国家自然科学基金重大项目“井筒工作液与天然气水合物储层作用机理和调控方法”(51991361);国家自然科学基金面上项目“深层裂缝性地层剪切响应型凝胶体系构筑与空间自适应堵漏机理”(52074327);中国石油天然气集团有限公司重大工程技术现场试验项目“恶性井漏防治技术与高性能水基钻井液现场试验”(2020F-45)。

摘　　要：针对裂缝性地层封堵层形成机理和封堵规则尚不明晰的问题,基于封堵实验和颗粒物质力学方法研究了裂缝性地层封堵层的形成过程,分析了封堵层组成及颗粒配比,揭示了封堵层形成的本质及破坏的驱动能量,提出了钻井液防漏堵漏颗粒优选规则。研究表明封堵层的形成过程经历了从惯性流、弹性流到准静态流的流态变化过程。封堵层由封端颗粒、架桥颗粒和填充颗粒组成,3种堵漏颗粒的配比是设计堵漏体系的重要依据。封堵层形成的本质是体系发生非平衡性Jamming相态转变,封堵层颗粒体系对压力的响应由熵力驱动,熵越大封堵层越稳定。根据提出的规则优选了堵漏材料、优化了堵漏体系,封堵效果优于其他常用规则,可有效提高封堵层承压能力,为解决裂缝性地层漏失提供了理论和技术依据。As formation mechanisms of plugging zone and criteria for fracture plugging remain unclear,plugging experiments and methods testing granular material mechanical properties are used to study the formation process of the plugging zone in fractured formations,analyze composition and ratios of different sizes of particles in the plugging zone,and reveal the essence and driving energy of the formation and damage of the plugging zone.New criteria for selecting lost circulation materials are proposed.The research results show that the formation of the plugging zone has undergone a process from inertial flow,elastic flow,to quasi-static flow.The plugging zone is composed of fracture mouth plugging particles,bridging particles and filling particles,and the proportion of the three types of particles is an important basis for designing drilling fluid loss control formula.The essence of the construction of the plugging zone is non-equilibrium Jamming phase transition.The response of the plugging zone particle system to pressure is driven by entropy force;the greater the entropy,the more stable the plugging zone.Lost circulation control formula optimized according to the new criteria has better plugging effect than the formula made according to conventional plugging rules and effectively improves the pressure-bearing capacity of the plugging zone.The research results provide a theoretical and technical basis for the lost circulation control of fractured formations.

关 键 词：裂缝性地层 钻井液漏失 封堵层 封堵机理 堵漏颗粒 优选规则 

分 类 号：TE345[石油与天然气工程—油气田开发工程]