A Research Progress of CO2-Responsive Plugging Channeling Gels.

In the heterogeneous reservoirs, CO₂ flooding easily leads to CO₂ gas channeling, which can seriously affect sweeping efficiency and reduce oil recovery. After thoroughly investigating the advantages and shortcomings of various CO₂ plugging technologies, this paper focuses on the feasibility of improving conventional water-alternating gas (WAG) through CO₂-responsive gel materials. Based on the different chemical reaction mechanisms between the unique chemical structure and CO₂, changes in the material's physical and chemical properties can respond to CO₂. The feasibility of utilizing these property changes for CO₂-responsive plugging is explored. Various CO₂-responsive gels and gel nanoparticles have been extensively researched in different fields, such as energy, medicine, and biology. This paper surveys the molecular structures, chemical compositions, response mechanisms, and changes of these CO₂-responsive gels, aiming to draw insights into the carbon dioxide-enhanced oil recovery (CO₂-EOR) field. Finally, the key issues and future development direction of CO₂-responsive plugging gels were analyzed. [ABSTRACT FROM AUTHOR]