塔里木致密裂缝性储层钻井液侵入实验研究  

Experimental Study on Mud Intrusion in Tarim Tightly Fractured Reservoirs

作　　者：黎明 郭建春[1] 刘彧轩 刘文辉[2] LI Ming;GUO Jianchun;LIU Yuxuan;LIU Wenhui(School of Petroleum Engineering,Southwest Petroleum University,Chengdu,Sichuan 610000;Tarim Branch,CNPC,Korla,Xinjiang 841000)

机构地区：[1]西南石油大学石油工程学院,成都610000 [2]中国石油塔里木油田分公司,新疆库尔勒841000

出　　处：《钻井液与完井液》2023年第5期586-593,共8页Drilling Fluid & Completion Fluid

基　　金：国家自然科学基金“深层页岩气压裂多裂缝的竞争起裂及扩展”(51874250)。

摘　　要：近年来致密砂岩储层伤害与保护问题引起学者们的关注。由于存在天然裂缝通道沟通,在裂缝性致密储层的开发过程中,工作液很容易沿裂缝进入储层,对储层造成严重的伤害。为了探究钻井液对裂缝性储层的伤害程度和机理,以塔里木库车山前区块裂缝性致密砂岩储层为研究对象,进行了钻井液侵入伤害实验。实验结果表明,钻井液侵入过程按照泥饼的形成过程可分为4个阶段,分别是无泥饼阶段、泥饼快速生成阶段、泥饼动态平衡阶段和形成封堵阶段;钻井液侵入速率受储层渗透率、泥饼渗透率、流体性质以及密度的影响,当储层渗透率高于临界渗透率时,侵入速率主要由滤饼渗透率决定;通过扫描电镜结果可得,钻井液固相颗粒在岩心孔喉中的堵塞状态分为堵塞状、黏附状和填充状3种,不同堵塞状态对储层渗透率伤害程度不同。得到的钻井液动态伤害分析与固相颗粒侵入研究有助于复杂油藏模拟器的改进,对现场施工作业以及钻井液优化具有一定的指导意义。In recent years,the problem of tight sandstone reservoir damage and protection has attracted the attention of scholars.Due to the existence of natural fracture channel communication,the fluids can easily enter the reservoir along the fractures during the development of fractured tight reservoirs and cause serious damage to the reservoir.In order to investigate the degree and mechanism of mud damage to fractured reservoirs,this paper conducts mud intrusion damage experiments with fractured tight sandstone reservoirs in Tarim Kucha Piedmont block as the research object.The experimental results show that the mud intrusion process can be divided into four stages according to the formation process of mud cake,namely,no mud cake stage,mud cake rapid generation stage,mud cake dynamic equilibrium stage and formation of sealing stage;the mud intrusion rate is affected by the reservoir permeability,mud cake permeability,fluid properties and specific gravity,and when the reservoir permeability is higher than the critical permeability,the intrusion rate is mainly determined by the filter cake permeability;by Scanning electron microscope results show that the blockage state of mud solid phase particles in core pore throat is divided into three kinds:blockage,adhesion and filling,and different blockage states have different degrees of damage to reservoir permeability.The mud dynamic damage analysis and solid-phase particle intrusion study obtained in this paper can help improve the complex reservoir simulator,which has certain guiding significance for the field construction operation and mud optimization.

关 键 词：钻井液 致密裂缝储层 侵入速率 固相颗粒 储层保护 

分 类 号：TE258[石油与天然气工程—油气井工程]