西安石油大学学报（自然科学版）2025，Vol.40Issue(3)：57-65,74,10.DOI:10.3969/j.issn.1673-064X.2025.03.006
基于微流控模型的超临界CO2压裂返排微观机制
Study on Microscopic Mechanism of Supercritical CO2 Fracturing Fluid Flowback Based on Microfluidic Model
摘要
Abstract
To reveal the backflow mechanism of supercritical CO2 fracturing fluid,a high-temperature and high-pressure microscopic vi-sualization experimental platform was designed,and a microfluidic model containing natural microcracks was fabricated to study the backflow law of supercritical CO2 fracturing fluid.And a comparison was made between the backflow characteristics and reservoir fluid migration and distribution laws of supercritical CO2 fracturing fluid and conventional water-based fracturing fluid.The results indicate that the compressibility and solubility of CO2 are important mechanism affecting the backflow of supercritical CO2 fracturing fluid.This mechanism results in almost no free residual CO2 in the formation,while also causing the slower backflow rate and longer backflow time of CO2 fracturing fluid.The angle between the direction of the fracture and the pressure gradient is the main factor affecting the backflow of fracturing fluid inside the fracture.When the angle is less than 45°,the driving effect of pressure on the fluid inside the fracture is more obvious,and the backflow effect is better;When the angle is greater than 45 °,the backflow effect is poor.The research results can provide a theoretical basis for the design of CO2 fracturing flowback technology.关键词
压裂液返排/超临界CO2/微裂缝/储层流体运移/微观可视化Key words
fracturing fluid flowback/supercritical CO2/micro crack/reservoir fluid migration/microscopic visualization分类
石油、天然气工程引用本文复制引用
谢平,王海柱,王斌,张云鹏,徐润滋,麦汉,董卓鑫..基于微流控模型的超临界CO2压裂返排微观机制[J].西安石油大学学报（自然科学版）,2025,40(3):57-65,74,10.基金项目
国家自然科学基金专项项目"页岩油储层超临界CO2聚能压裂与封存基础研究"(52341401) （52341401）
丝绸之路经济带创新驱动发展试验区、乌昌石国家自主创新示范区科技发展计划项目"超临界CO2聚能脉冲压裂造缝机理与关键技术研究及应用"(2023LQ03005) （2023LQ03005）
