Proceedings of SPE/DOE Symposium on Improved Oil Recovery · 2004 · 69 citations · 0 references
Natural SciencesEarth SciencesEnvironmental EngineeringGeochemistryReservoir EngineeringReservoir SimulationBiogeochemical Cycle ModelingCompositional SimulationGeologic Carbon StorageGroundwater ModelingAquifer ModelingAquifer SimulationAquifer StorageAquifer Storage ModelingCompositional ModelingCompositional Reservoir SimulationGeochemical ModelingGroundwater Simulation
The study presents a fully coupled geochemical compositional EOS simulator for modeling CO₂ storage in saline aquifers. The GEM‑GHG simulator jointly solves convective and dispersive flow, phase equilibrium among oil, gas, and aqueous phases, aqueous chemical equilibrium, and mineral dissolution/precipitation kinetics to ensure numerical robustness. Field‑scale simulations demonstrate CO₂(g) and CO₂(aq) migration, CO₂(aq) dissociation to HCO⁻ and subsequent carbonate mineralization, with high‑density CO₂‑rich brine plumes convecting and mineralizing around them.
Abstract This paper describes a fully coupled geochemical compositional Equation-of-State (EOS) compositional simulator for the simulation of CO2 storage in saline aquifers. The simulator (GEM-GHG) models the following phenomena: (1) convective and dispersive flow in porous media; (2) phase equilibrium between the oil, gas and aqueous phase; (3) chemical equilibrium for reactions between the aqueous components and (4) mineral dissolution and precipitation kinetics. For numerical robustness and stability, all equations are solved simultaneously. The simulator is applied to the simulation of typical field-scale CO2 sequestration processes, showing the migration of CO2(g) and CO2(aq), the dissociation of CO2(aq) into HCO− and its subsequent conversion into carbonate minerals. Convection of high-density plumes of CO2-rich brine in conjunction with CO2 mineralization around the plumes is illustrated.