石油钻采工艺2025，Vol.47Issue(4)：452-463,12.DOI:10.13639/j.odpt.202503011
基于动静态实验与核磁共振技术的低渗透砂岩储层酸岩溶蚀机制研究
Study on acid rock dissolution mechanism of low-permeability sandstone reservoirs based on dynamic and static experiments and nuclear magnetic resonance technology
摘要
Abstract
It is crucial for optimizing acid fluid selection and enhancing acidification effect to investigate the acid rock dissolution mechanism of low-permeability reservoirs and clarify the impact of such factors as shale content and acid fluid concentration on dissolution efficiency.Combining two experimental approaches—static dissolution(mineral rock plate at 20～60℃)and dynamic flow(with acid fluid concentration 1%～5%,core permeability(0.1～1)×10-3 μm2,and shale content 8%～44%),the dissolution laws of hydrochloric acid,mud acid,and acetic acid were analyzed under various influencing factors.In addition,nuclear magnetic resonance online monitoring technology was introduced to evaluate the changes in pore configuration before and after acid displacement.The results show that quartz exhibits strong acid resistance(dissolution rate<3%after 24 hours),while montmorillonite is easily dissolved(dissolution rate of 54.46%after 24 hours).As the temperature rises,the dissolution rate gradually increases.Increases in rock permeability,acid fluid concentration,and shale content all contribute to enhanced acid dissolution.Therefore,high-permeability cores present better acidizing effect than low-permeability cores.After displacement with 5%mud acid,the optimal dissolution effect is achieved,core porosity is increased by 14.39%and permeability improved by 76.30%.Overall,clay minerals(particularly montmorillonite)are key factors influencing acidizing efficiency.The use of 5%mud acid is recommended for acidizing low-permeability sandstone reservoirs with shale content≥20%.The application of nuclear magnetic resonance-mercury penetration coupling technique improves the accuracy of pore configuration description by over 10%.关键词
低渗透砂岩储层/酸化/溶蚀规律/核磁共振/泥质含量/动静态实验Key words
low-permeability sandstone reservoir/acidification/dissolution law/NMR/shale content/dynamic and static experiments分类
能源科技引用本文复制引用
王昭凯,牟倩楠,赵红雨,张永波,吕东方,李哲,赵光..基于动静态实验与核磁共振技术的低渗透砂岩储层酸岩溶蚀机制研究[J].石油钻采工艺,2025,47(4):452-463,12.基金项目
国家自然科学基金联合基金项目"海上稠油CO2反应增黏聚表剂驱油体系构建及作用机制"(编号:U23B2087). （编号:U23B2087）
