CO2 convective dissolution in water-saturated unconsolidated porous media at reservoir conditions

9 Pages Posted: 26 Mar 2021

See all articles by Widuramina Amarasinghe

Widuramina Amarasinghe

NORCE Norwegian Research Centre AS; University of Stavanger - Faculty of Science and Technology

Ingebret Fjelde

NORCE Norwegian Research Centre AS; University of Stavanger

Nils Harald Giske

NORCE Norwegian Research Centre AS

Ying Guo

NORCE Norwegian Research Centre AS

Date Written: March 24, 2021

Abstract

During CO2 storage into saline aquifers, CO2 plume mixes with the fluid phases present in the reservoir mainly due to diffusion. The mixing process creates a density gradient (e.g. increase the density of water/brine). This phenomenon leads to a convective flow which will accelerate the CO2 mixing and mass transfer which will significantly enhance the underground CO2 storage rate. It is important to know the transport rate of CO2 through a porous media pack during this convective mixing process to get a better understanding of the CO2 mixing process. Hence CO2 convective dissolution experiments were conducted in vertically packed unconsolidated porous media at 100 bar and 50 °C. Porous media with the permeability of 0.5 D, 4 D, 16 D, and 76 D were prepared using glass beads of different sizes. A high-pressure 3D steel column cell was used, with a Bromothymol blue water solution-filled sapphire cell connected at the bottom. Colour change inside the sapphire cell was used as an indication of the CO2-breakthrough. Pressure decay of the system as a result of CO2 dissolution and convection was monitored along with CO2 breakthrough through the porous media. It has been found that CO2 transport rate in bulk fluid (i.e. without porous media) is 4.3 mm/min, with repeatable consistency. With increasing Rayleigh number, the CO2 transport rate was found to increase as a function of power in the form of V=a2*Ra^(b2) in 3D experiments. Comparing the results with 2D experiments (i.e. conducted in Hele-Shaw cells) few differences were identified. It has identified that the differences between 2D and 3D-experiments were due to geometry, boundary effects, slight heterogeneities within the porous pack, and the contact area between CO2 and porous media. It has also been found out that Ra number and dimensionless time have a relationship in the form of power (Ra=c*τ^(-n)) in 3D space.

Keywords: Convection, Porous media, Reservoir conditions, CO2 dissolution, 3D steel column

Suggested Citation

Amarasinghe, Widuramina and Fjelde, Ingebret and Giske, Nils Harald and Guo, Ying, CO2 convective dissolution in water-saturated unconsolidated porous media at reservoir conditions (March 24, 2021). Proceedings of the 15th Greenhouse Gas Control Technologies Conference 15-18 March 2021, Available at SSRN: https://ssrn.com/abstract=3811776 or http://dx.doi.org/10.2139/ssrn.3811776

Widuramina Amarasinghe (Contact Author)

NORCE Norwegian Research Centre AS ( email )

P.O.B. 22 Nygårdstangen
Bergen, NO-5838
Norway

University of Stavanger - Faculty of Science and Technology ( email )

Norway

Ingebret Fjelde

NORCE Norwegian Research Centre AS

P.O.B. 22 Nygårdstangen
Bergen, NO-5838
Norway

University of Stavanger

PB 8002
Stavanger, 4036
Norway

Nils Harald Giske

NORCE Norwegian Research Centre AS ( email )

P.O.B. 22 Nygårdstangen
Bergen, NO-5838
Norway

Ying Guo

NORCE Norwegian Research Centre AS ( email )

P.O.B. 22 Nygårdstangen
Bergen, NO-5838
Norway

Do you have a job opening that you would like to promote on SSRN?

Paper statistics

Downloads
67
Abstract Views
388
Rank
664,667
PlumX Metrics