Injectivity and quantification of capillary trapping for CO₂ storage: A review of influencing parameters

CO₂ injection for storage in subsurface geologic medium is one of the techniques developed in the past years to mitigate anthropological CO₂. Prior to CO₂ injection, it is essential to predict the feasibility of medium in terms of storage capacity, injectivity, trapping mechanisms, and containment. There have been many studies regarding techniques which can be applied to ensure the safety of CO₂ injection. However, there are few studies indicating the importance of capillary trapping during and after CO₂ injection. The aim of this study is to review the fundamentals of injectivity and its relationship with capillary trapping for CO₂ storage in depleted oil and gas reservoirs. Considering the number of effective parameters which are associated with the injectivity and capillary trapping, it is recommended to perform a comprehensive analysis to determine the optimum injection rate and safe storage medium before operation.