Managing Geologic CO2 Storage with Pre-injection Brine Production in Tandem Reservoirs

Abstract We present an approach for managing geologic CO 2 storage using wells that serve three sequential purposes (1) characterization and monitoring, (2) brine production, and (3) CO 2 injection. Two reservoirs are deployed in tandem: (1) a CO 2 -storage reservoir and (2) a brine-storage reservoir. This approach provides data that can be analyzed prior to CO 2 injection, enabling proactive reservoir management, which reduces cost and risk. We analyze a range of brine-disposition options, including 100% reinjection in a nearby brine-storage reservoir and cases where a portion of the produced brine is used to generate water, with the residual brine reinjected in the nearby reservoir. We also consider the option of time-shifting the parasitic load of brine production and injection, so that those operations can utilize excess energy from electric grids during periods of over-generation.