EGU23-17055
https://doi.org/10.5194/egusphere-egu23-17055
EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Convective dissolution of carbon dioxide in 2D water-saturated porous media: an experimental study in two-dimensional micromodels

Niloy De1, Naval Singh2, Remy Fulcrand3, Yves Méheust4, Patrice Meunier5, and François Nadal1,6
Niloy De et al.
  • 1Wolfson school of Mechanical,Electrical and Manufacturing Engineering, Loughborough University, Loughborough, UK (niloy@alumni.iitg.ac.in)
  • 2School of Chemical Engineering, Loughborough University, Loughborough, UK
  • 3Institut Lumière Matière, CNRS, Université Claude Bernard, Villeurbanne, France
  • 4University of Rennes, CNRS, Geosciences Rennes (UMR 6118), 35042 Rennes, France
  • 5IRPHE, Aix-Marseille université, CNRS, Centrale Marseille, Marseille, France
  • 6CEA, Bordeaux, France

Convective dissolution is a perennial trapping mechanism of carbon dioxide in geological formations saturated with an aqueous phase. This process, which couples dissolution of supercritical CO2, convection of the liquid containing the dissolvedCO2, and mixing of the latter within the liquid, has so far not been studied in two-dimensional porous media. In order to do so, two-dimensional (2D) porous micromodels (patterned Hele-Shaw cells) have been fabricated from UV-curable NOA63 glue. NOA63 is used instead of PDMS, which is permeable to CO2 and does not allow for a controlled no flux boundary condition at the walls. The novel fabrication protocol proposed here, based on the bonding of a patterned photo-lithographed NOA63 layer on a flat NOA63 base, shows good reproducibility regardless of the pattern’s typical size, and allows for easy filling of the cell despite the small value of the gap. A pressure chamber allows pressurizing the CO2 and outside of the flow cell up to 10 bars. Experiments were performed in 11 different porous media geometries. As expected, a gravitational fingering instability is observed upon injection of gaseous carbon dioxide in the cell, resulting in the downwards migration of dissolved CO2 plumes through the 2D porous structure. The initial wavelength of the fingers is larger in the presence of a hexagonal lattice of pillars. This effect can be correctly predicted from the theory for the gravitational instability in a Hele-Shaw cell devoid of pillars, provided that the permeability of the hexagonal porous medium is considered in the theory instead of that of the Hele-Shaw cell. Fluctuations around the theoretical prediction observed in the data are mostly attributed to a hitherto unknown weak locking of the wavelength on the distance between closest pillars.

How to cite: De, N., Singh, N., Fulcrand, R., Méheust, Y., Meunier, P., and Nadal, F.: Convective dissolution of carbon dioxide in 2D water-saturated porous media: an experimental study in two-dimensional micromodels, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-17055, https://doi.org/10.5194/egusphere-egu23-17055, 2023.

Supplementary materials

Supplementary material file