Using Reservoir Geology and Petrographic Observations to Improve CO2 Mineralization Estimates: Examples from the Johansen Formation, North Sea, Norway

Abstract

Reservoir characterization specific to CO2 storage is challenging due to the dynamic interplay of physical and chemical trapping mechanisms. The mineralization potential for CO2 in a given siliciclastic sandstone aquifer is controlled by the mineralogy, the total reactive surface areas, and the prevailing reservoir conditions. Grain size, morphologies and mineral assemblages vary according to sedimentary facies and diagenetic imprint. The proposed workflow highlights how the input values for reactive mineral surface areas used in geochemical modelling may be parameterized as part of geological reservoir characterization. The key issue is to separate minerals both with respect to phase chemistry and morphology (i.e., grain size, shape, and occurrence), and focus on main reactants for sensitivity studies and total storage potentials. The Johansen Formation is the main reservoir unit in the new full-value chain CO2 capture and storage (CCS) prospect in Norway, which was licenced for the storage of CO2 as of 2019. The simulations show how reaction potentials vary in different sedimentary facies and for different mineral occurrences. Mineralization potentials are higher in fine-grained facies, where plagioclase and chlorite are the main cation donors for carbonatization. Reactivity decreases with higher relative fractions of ooidal clay and lithic fragments.

Impact of the lower Jurassic Dunlin Group depositional elements on the Aurora CO2 storage site, EL001, northern North Sea, Norway

“…12). Textures and reactive mineral assemblies are comparable to previous studies (Sundal and Hellevang, 2019), providing permeable sandstone with significant potential for immobilizing CO 2 through residual, dissolution and mineral trapping. Estimated moderate kinetic reaction rates improve storage security without compromising injectivity (Sundal et al, 2021).…”

“…Although still reservoir-grade sandstones, the higher mudstone content and the smaller spatial dimensions of the dominant discrete heterogeneities suggest even higher reservoir sweep potential (Fig. 10B and C), which would enhance the effect of physical and chemical trapping (Sundal et al, 2015;Sundal and Hellevang, 2019). Overall, high lateral connectivity throughout the Johansen Formation interval is supported by the interpretation of the results from the drill stem test performed in Eos, showing no indications of compartmentalization and high pressure dissipation capacity in the estimated investigation radius of 2 to 3 km (Meneguolo et al, 2020).…”

The Ratio of Chemical and Physical CO2 Absorption Capacity in Triethanolamine and Methyl-diethanolamine Solution Systems

“…Recently, in response to climate change, researchers have reported on many carbon capture and storage (CCS) technologies intended for practical use. − Among them, the chemical absorption process using amine-based solutions as the solvent has been commercialized due to its advantages such as its relatively high economic feasibility and fast reaction rate. − Monoethanolamine (MEA), one of the primary amines, reacts directly with CO 2 to generate protonated amine and carbamate ions, and it is currently considered to be the most optimum solvent for chemical absorption because of its high absorption rate and low solvent price; therefore, several CCS plants employing MEA as the solvent have been commercially operated in the USA, Canada, and China. − However, MEA aqueous systems can still be improved upon; for example, they can be made more economical by improving their utilization limit (lower than 0.5 mol of CO 2 /mol of MEA in a high-concentration solution) and substantial energy consumption for solvent regeneration. Therefore, some MEA–organic solvent (water-free or water-lean) systems using monoethylene glycol, methanol, acetone, and tetrahydrofurfuryl alcohol as the organics are an alternative to enhance the amine utilization increasing the physical absorption capacity of the systems. − …”

Editorial for Special Issue “Geological and Mineralogical Sequestration of CO2”

“…The studies by Saftić et al [10], Koukouzas et al [11] and Sundal and Hellevang [12] tackle this issue by providing geological information on the storage potential of selected areas in Croatia, Greece and Norway. In particular, Saftić et al [10] performed a potential assessment of three prospect areas in the southern part of the Pannonian basin, in the Northern and Central Adriatic Sea, by taking advantage of a detailed stratigraphic knowledge of the Croatian territory derived from previous oil prospection activity.…”

“…By combining reservoir geology, petrographic observation and geochemical modelling techniques, Sundal and Hellevang [12] assessed the storage capacity of a specific reservoir in the Northern Sea, Norway. In this study, the specific reactive areas of minerals used in the numerical simulations were proposed as an additional parameter to be considered for the geological characterization of the reservoir.…”