Large Volume CO2 Storage and Plume Management in the Southeastern U.S.; Reservoir Characterization and Simulation

Abstract

This paper summarizes a reservoir simulation study to evaluate the potential storage of 675 million metric tons of CO2 over 30 years at the Project ECO2S storage site—a 12,000-hectare storage complex adjacent to Mississippi Power Company’s (MPC) Plant Ratcliffe facility in Kemper County, Mississippi, USA. The project team studied the storage capacity of the target formations, estimated the CO2 plume size, performed a sensitivity analysis to examine the influence of reservoir and fluid properties, and tested the impact of active plume management—a process that includes extracting water from down-dip water production wells and re-injecting it through up-dip water injection wells within the storage formation—on CO2 plume migration and its extent. The ECO2S site appears to be capable of storing captured CO2 emissions from multiple Southern Company operated power sources, which together emit 22.5 million metric tons per year (675 million metric tons over 30 years). To investigate field development strategies for large volume CO2 injection and storage at ECO2S, the project team developed a base model using the latest geological interpretation. Thirty years of CO2 injection is simulated through seven injection pads with each pad hosting three injection wells, positioned in the center of the potential storage site, followed by 30 years of CO2 plume monitoring. The simulation results show that the 675 million metric tons of CO2 can be injected into the storage formations, safely and securely. The largest CO2 plume, which occurs in the shallowest reservoir, covers a 202-square kilometer area. Active plume management shows a small impact on controlling the plume size and its migration due to extremely high vertical permeability minimizing the impact of the water curtain. Project ECO2S is part of the CarbonSAFE Program and is financially supported by the USDOE-NETL and Mississippi Power Company. The project is managed by the Southern States Energy Board. Technical Support is provided by Southern Company Research and Development.