Release Time:2019-03-13  Hits:

Indexed by: Journal Article

Date of Publication: 2016-06-01

Journal: GREENHOUSE GASES-SCIENCE AND TECHNOLOGY

Included Journals: Scopus、EI、SCIE

Volume: 6

Issue: 3

Page Number: 401-415

ISSN: 2152-3878

Key Words: CO2 storage; heterogeneity; porous media; wettability; X-ray CT

Abstract: The geological sequestration of carbon dioxide (CO2) is considered a promising technology for CO2 emissions. However, accurate estimation of the storage capacity for CO2 remains a challenge owing to the effect of capillary pressure variation. The CO2-salty aqueous contact angle and sub-core scale heterogeneity are the major factors that influence capillary pressure. This paper reports the results of CO2/brine two-phase flow experiments in porous media by using an X-ray computed tomography (CT) technique at 40 degrees C and 8 Mpa and examines the strong influence of wettability and sub-core scale heterogeneities on the spatial distribution of CO2. Gas injection experiments were conducted at flow rates of 0.1 mL/min, 0.2 mL/min, and 0.5 mL/min, and the porous media were packed with feldspar, quartz, or dolomite. This study indicates that at the core scale, the wettability of porous media is a crucial factor in determining CO2 saturation. Capillary fingering and low CO2 saturation occurred with high water wettability. Sub-core scale heterogeneities controlled the CO2 distribution and saturation variation along the porous media, particular that with small pore sizes. (c) 2015 Society of Chemical Industry and John Wiley & Sons, Ltd