Progress of CO2 EOR and Storage Technology

Abstract

CO2 flooding is one of the most promising EOR technologies. The laboratory experiments have gradually evolved from early basic experiments to the revelation of physicochemical mechanisms and multi-scale physical simulation studies. The numerical simulation method moves toward the novel numerical simulation coupling compositional simulation with geochemical reaction and the stress field. Moreover, the optimization method starts to focus on the multi-objective optimization of CO2 EOR and storage. Meanwhile, stratified gas injection processes and tools are crucial to implement balanced gas injection. The corrosion prevention technology is required to combine anti-corrosive materials and corrosion inhibitors. The injection-production adjustment is the priority to be considered in the early stage of gas injection. The chemical-assisted suppression methods, including foam agent, particles, and gel, are needed to implement in the later stage of gas injection. Gas channeling treatment with hierarchical management is crucial to tailor the different channeling channels. A full-chain optimization model based on net emission reduction and carbon footprint is suggested for the future system planning of CO2 EOR and storage. In general, the next-generation CO2 EOR technology not only aims to significantly increase the oil recovery but also achieves large-scale CO2 storage, providing strong support for carbon neutrality goals.