摘要
钻井液滤失是一个时间长且复杂的过程,泥浆成分、地层压力、温度和渗透率是影响滤失行为的关键因素。随着在高温和高压区域钻进的深入,需引入预测滤液侵入和颗粒桥接的研究。通过在基础水基泥浆中添加重晶石和不同粒径大小的碳酸钙来研究颗粒桥接、滤液侵入和渗透性对其造成的影响。通过渗透率为15.9~653 mD的砂岩岩心在不同时间进行高温高压滤失测试的方式来模拟颗粒桥接效应。该研究还利用分析模型来计算使用不同混合设计的试验的泥饼渗透率。通过扫描电子显微镜(SEM)分析颗粒侵入随深度和时间的预期趋势。结果表明:碳酸钙颗粒大小与滤失损失成正相关,多孔介质的渗透性是影响累积滤失量的关键因素;重晶石将充填岩心中微孔隙,颗粒分布较为均匀且致密,使得岩心渗透率得以降低。本研究的结果可用于设计井筒强化流体,以减轻井眼稳定性和地层损害。
Drilling fluid filtration loss is a long and complex process.Mud composition,formation pressure,temperature and permeability are the key factors affecting filtration loss behavior.As drilling progresses in high temperature and pressure areas,studies on predicting filtrate intrusion and particle bridging need to be introduced.In this paper,the effects of particle bridging,filtrate intrusion and permeability were investigated by adding barite and calcium carbonate of different particle sizes to the base water-based mud.The particle bridging effect was simulated by means of high-temperature and high-pressure filtrate loss tests at different times in sandstone cores with permeabilities ranging from 15.9 mD to 653 mD.The study also used analytical models to calculate mudcake permeability for tests using different mixing designs.Expected trends in particle intrusion with depth and time were analyzed by scanning electron microscopy(SEM).The results showed that calcium carbonate particle size was positively correlated with filtration loss and that the permeability of the porous media was a key factor in the cumulative filtration loss;barytes filled the micropores in the core with a more uniform and dense particle distribution,allowing the core permeability to be reduced.The results of this study can be used to design wellbore-enhancing fluids to mitigate borehole stability and formation damage.
作者
张大力
李文明
贾涛
郭良
王明明
ZHANG Da-li;LI Wen-ming;JIA Tao;GUO Liang;WANG Ming-ming(Sinopec Shengli Petroleum Engineering Company Yellow River Drilling Corporation,Dongying Shandong 257000,China)
出处
《当代化工》
CAS
2023年第7期1619-1623,共5页
Contemporary Chemical Industry
基金
国家自然科学基金项目“页岩油气高效开发基础理论”(项目编号:51490653)
中国石化科技攻关项目“鄂南致密油藏两级裂缝高导流复合压裂技术研究”(项目编号:P17005-5)联合资助。
关键词
钻井液
泥饼
渗透率
高温高压
井壁稳定
Drilling fluid
Mud cake
Permeability
High temperature and high pressure
Wellbore stability
