TY - JOUR
T1 - Effect of impurities on the onset and growth of gravitational instabilities in a geological CO2 storage process
T2 - Linear and nonlinear analyses
AU - Kim, Min Chan
AU - Song, Kwang Ho
N1 - Funding Information:
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2015R1D1A3A01015798).
Publisher Copyright:
© 2017 Elsevier Ltd
PY - 2017
Y1 - 2017
N2 - Because 75% of the total cost of carbon capture and storage (CCS) arises from the separation of CO2 from gas streams (Nsakala et al., 2001), the co-injection of CO2 and impurities such as H2S, N2, and SO2 is considered a cost-effective alternative to pure CO2 geological sequestration. Here, the effect of the impurities on the onset of gravitational instability has been analyzed theoretically and numerically. Linear stability equations have been derived and solved analytically and numerically. Double diffusive effects make the system stable or unstable depending on the values of the diffusivity ratio, δB, and buoyancy ratio, rβrC. In addition, using the Fourier spectral method, we have traced the temporal evolution of the gravitational fingers numerically. The shape and the growth history of the fingers are strongly dependent on the impurity content. The time-periodic oscillatory motions are not observed in the present linear and nonlinear analyses. For a given Rayleigh number, the dissolution of N2 and H2S impurities makes the system stable, whereas dissolved SO2 accelerates the onset of instability.
AB - Because 75% of the total cost of carbon capture and storage (CCS) arises from the separation of CO2 from gas streams (Nsakala et al., 2001), the co-injection of CO2 and impurities such as H2S, N2, and SO2 is considered a cost-effective alternative to pure CO2 geological sequestration. Here, the effect of the impurities on the onset of gravitational instability has been analyzed theoretically and numerically. Linear stability equations have been derived and solved analytically and numerically. Double diffusive effects make the system stable or unstable depending on the values of the diffusivity ratio, δB, and buoyancy ratio, rβrC. In addition, using the Fourier spectral method, we have traced the temporal evolution of the gravitational fingers numerically. The shape and the growth history of the fingers are strongly dependent on the impurity content. The time-periodic oscillatory motions are not observed in the present linear and nonlinear analyses. For a given Rayleigh number, the dissolution of N2 and H2S impurities makes the system stable, whereas dissolved SO2 accelerates the onset of instability.
KW - CO sequestration
KW - Gravitational fingering
KW - Impurity
KW - Solubility trapping
KW - Stability analysis
UR - http://www.scopus.com/inward/record.url?scp=85029798135&partnerID=8YFLogxK
U2 - 10.1016/j.ces.2017.09.038
DO - 10.1016/j.ces.2017.09.038
M3 - Article
AN - SCOPUS:85029798135
VL - 174
SP - 426
EP - 444
JO - Chemical Engineering Science
JF - Chemical Engineering Science
SN - 0009-2509
ER -