Caprock Interactions with the Supercritical CO2 and Brine: A Labratory Study of the Effects of Simulated Geological CO2 Sequestration on Shales from the Black Warrior River Basin, Alabama L

Author

Jessica E. RainesFollow

Date of Award

Fall 8-15-2012

Degree Type

Thesis

Degree Name

Master of Science (MS)

Department

Geosciences

First Advisor

Daniel M. Deocampo

Second Advisor

W. Crawford Elliott

Third Advisor

Seth E. Rose

Abstract

A better understanding of the brine-rock- supercritical CO₂ interaction is needed to evaluate the risks of geologic CO₂ sequestration. The geochemical effects of brine and supercritical CO₂ were examined via laboratory modeling of in situ conditions on two reservoir caprocks in the Black Warrior River Basin, the Pottsville and Parkwood Formations. The clay fraction was extracted and treated at ~ 100 bar and 363 K (90 °C) over periods of up to 70 hours. Supercritical CO₂ was introduced as dry ice in a pressurized vessel. Samples were observed using XRD, WD-XRF, AA, SEM, and EDS. Clay fractions contained Fe-chlorite, illite, kaolinite, and quartz. Results show the dissolution of illite, CO₂-brine induced cation exchange ok K⁺, and the dissolution of silicate minerals. Steady-state K/Si ratios in the fluid suggest quartz re-precipitation. These interactions could adversely affect the long-term storativity of the caprock and point to a need for further study.

DOI

https://doi.org/10.57709/3228829

Recommended Citation

Raines, Jessica E., "Caprock Interactions with the Supercritical CO2 and Brine: A Labratory Study of the Effects of Simulated Geological CO2 Sequestration on Shales from the Black Warrior River Basin, Alabama L." Thesis, Georgia State University, 2012.
doi: https://doi.org/10.57709/3228829