3D Pressure-limited approach to model and estimate CO2 injection and storage capacity: saline Mount Simon Formation

Abstract

To estimate the carbon dioxide (CO2) injection and storage capacity of saline formations, we used Tough2-ECO2N simulation software to develop a pressure-limited (dynamic) simulation approach based on applying three-dimensional (3D) numerical simulation only on the effective injection area (Aeff) surrounding each injection well. A statistical analysis was performed to account for existing reservoir heterogeneity and property variations. The accuracy of the model simulation results (such as CO2 plume extension and induced injection well bottomhole pressure values) were tested and verified against the data obtained from the Decatur CO2 injection study of the Mount Simon Formation. Next, we designed a full-field CO2 injection pattern by populating the core sections of this formation with a series of the simulated effective injection areas such that each simulated Aeff acts as a closed domain. The results of this analysis were used to estimate the optimum number and location of the required CO2 injection wells, along with the dynamic annual CO2 injection rate and overall pressure-limited storage capacity of this formation. This approach enabled us to model separate CO2 injection activities independently at different sections of the same saline formation and to model and simulate faults and natural barriers by considering them as boundary conditions for each simulated Aeff without constructing full-field models. Using this approach, a series of modeled Aeff with relevant properties may be redesigned to model any other saline formation with a similar structure. © 2017 The Authors. Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons, Ltd.