Natural Mitigation of CO2 Leakage Accumulations

Jean-Charles Manceau (1) , Jeremy Rohmer (1) , Arnaud Réveillère (1)

1 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)

This study aims at investigating the role played by the overlying aquifer formation as a safety barrier in case of CO 2 leakage accumulation (i.e. CO 2 accumulated in an overlying aquifer after its leakage from the CO 2 storage reservoir) by focusing on its natural capacity to prevent any further upward migration. Based on numerical simulations performed using TOUGH2/ECO2N incl. hysteretic module, we assess the processes influencing the quantity of mobile CO 2 within the leaking plume and perform a sensitivity analysis to point out the key-parameters and conditions for an efficient natural trapping by dissolution and residual trapping. Additional simulations of a leakactive remediation scenario on a complete system (storing reservoir connected to an overlying aquifer) show the importance of the natural trapping capacity of the overlying aquifer. This capacity could be integrated in the mitigation strategy, associating natural and engineered safety barriers. Gaining more knowledge on these formations f f can support first estimations of this natural capacity, and hence can help building the corrective measure plan and designing potential interventions during operations.

Mots clés: CO2 geological storage; leakage; mitigation; overlying aquifer; trapping; CO2 geological storage

Domaines: Sciences de la Terre

Jean-Charles Manceau, Jeremy Rohmer, Arnaud Réveillère. Natural Mitigation of CO2 Leakage Accumulations. Energy Procedia, 2013, Energy Procedia, 37, pp.4400-4408. ⟨10.1016/j.egypro.2013.06.345⟩. ⟨hal-03662738⟩