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Indexed by:期刊论文

Date of Publication:2016-01-01

Journal:RSC ADVANCES

Included Journals:SCIE、EI

Volume:6

Issue:115

Page Number:114320-114328

ISSN No.:2046-2069

Abstract:A clear understanding of the mass transfer properties during fluid injection into porous media is of importance to the safety of CO2 storage. In this study, several experiments were conducted to elucidate the displacement and dissolution processes of gaseous and supercritical CO2 in Berea sandstones using the X-ray CT technology. The initial CO2 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 CO2 saturation was determined by imaging analysis. Both supercritical and gaseous CO2 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 CO2 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 CO2 storage.