Chemo-Poromechanical Study of Wellbore Cement Integrity

This chapter focuses on the behavior of the cement sheath constituting the injection well. This cement will indeed be subjected to rapid reactions provoked by the presence of carbon dioxide in the storage complex. Such a focus is legitimized by the fact that wells are seen as one of the main discontinuities in the storage sealing complex that could turn into preferential pathways for CO2 leaks toward the biosphere. Even though CO2 resistant cements will be used, abandoned wells could be present in the storage site and be in contact with CO2. The chapter presents a chemo-poromechanical framework for chemo-poromechanical modeling of chemical reactions (dissolution/precipitation phenomena). Then, the chapter discusses its application to cement carbonation and its implementation into a numerical code. A simplified analysis, representative of CO2 geological storage, is finally performed to assess the capabilities of the numerical tool thus developed.