During his participation in the 10th Scientific and Engineering Conference on “Supercritical Fluids: Fundamentals, Technologies, Innovations”, Prof. Andrey Kalinichev from ARMINES Subatech (Nantes, France) gave a lecture on “Supercritical carbon dioxide in the nanopores of minerals and cementitious materials under conditions of geological carbon sequestration.”
Injection of supercritical CO2 into deep geological formations and depleted oil and gas reservoirs is an effective method for enhanced oil recovery and a promising pathway for reducing anthropogenic CO2 emissions contributing to global climate change. One of the anticipated problems for the large-scale application of geological carbon capture and sequestration (CCS) technologies is the potential degradation of cement wellbore casings due to their exposure to supercritical CO2, which can pose significant environmental risks. To minimize these risks and to optimize stable and reliable CCS operations, a detailed molecular level understanding of the interactions between cement and CO2 rich fluids is necessary, as well as clear understanding of the fluid transport pathways in wellbore cement materials. In addition, the long-term effectiveness of fluid CO2 confinement is strongly dependent on its interaction with host rocks (mostly sedimentary minerals, such as various clays, quartz, carbonates, etc.), rock nanoporosity, temperature, pressure and other factors.
Methods of atomistic computational modeling are very well suited for providing such internally consistent molecular-scale information on the interaction of supercritical CO2 with various materials, thus greatly improving our understanding of the specific effects of the substrate structure and composition on the structure, dynamics and reactivity of the interfacial and nano-confined CO2 rich solutions. In this talk, a brief overview of our most recent atomistic modeling results will be presented for several cement-related and clay-related systems, in contact with CO2-H2O and CO2-CH4 mixtures under T/P conditions typical for geological CO2 sequestration and application of supercritical CO2 for enhanced oil recovery.
Please find the full abstract here