Characterization of dissolution process during brine injection in Berea sandstones: an experiment study

• Published in: RSC advances Vol. 6; no. 115; pp. 11432 - 114328
• Main Authors: Jiang, Lanlan, Yu, Minghao, Wu, Bohao, Suekane, Tetsuya, Li, Weizhong, Song, Yongchen
• Format: Journal Article
• Language: English
• Published: 01.01.2016
• Subjects: Carbon dioxide; Dissolution; Flow rate; Heterogeneity; Mass transfer; Salt water; Sandstones; Saturation
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/c6ra19024c

A clear understanding of the mass transfer properties during fluid injection into porous media is of importance to the safety of CO 2 storage. In this study, several experiments were conducted to elucidate the displacement and dissolution processes of gaseous and supercritical CO 2 in Berea sandstones using the X-ray CT technology. The initial CO 2 distribution before brine injection was related to the pore structure of the sandstones. Transient images during brine injection at different flow rates showed a transformation from displacement to dissolution, and the dissolution fronts were affected by the core heterogeneity and flow rates. Then, the CO 2 saturation was determined by imaging analysis. Both supercritical and gaseous CO 2 saturation decreased sharply, meaning that dissolution dominated the flow process. The dissolution time could be correlated in terms of the flow rate, initial gas saturation and heterogeneity of the sandstone. The relationships between CO 2 volume content and specific surface area were verified to qualitatively predict the influence of heterogeneity. The dynamic concentration and mass transfer coefficient were obtained, which gave the information for the mass transfer rate during CO 2 storage. A clear understanding of the mass transfer properties during fluid injection into porous media is of importance to the safety of CO 2 storage.