Synchrotron-based X-ray microtomography (micro CT) at the Advanced Light Source (ALS) line 8.3.2 at the Lawrence Berkeley National Laboratory produces three-dimensional micron-scale-resolution digital images of the pore space of the reservoir rock along with the spacial distribution of the fluids. Pore-scale visualization of carbon dioxide flooding experiments performed at a reservoir pressure demonstrates that the injected gas fills some pores and pore clusters, and entirely bypasses the others. Using 3D digital images of the pore space as input data, the method of maximal inscribed spheres (MIS) predicts two-phase fluid distribution in capillary equilibrium. Verification against the tomography images shows a good agreement between the computed fluid distribution in the pores and the experimental data. The model-predicted capillary pressure curves and tomography-based porosimetry distributions compared favorably with the mercury injection data. Thus, micro CT in combination with modeling based on the MIS is a viable approach to study the pore-scale mechanisms of CO2 injection into an aquifer, as well as more general multi-phase flows.
Bibliographical noteFunding Information:
Acknowledgements This work was partially supported by the U.S. Department of Energy’s Assistant Secretary for Coal through the Zero Emission Research and Technology Program under US Department of Energy contract no. DE-AC02-05CH11231 to Lawrence Berkeley National Laboratory. Part of this work has been done while the first author was visiting the Energy Resources Engineering Department at Stanford University. The hospitality of this department and the Global Climate and Energy Project is gratefully appreciated. The first author also acknowledges partial support from the Research Partnership to Secure Energy for America. Portions of this work were performed at the ALS, Lawrence Berkeley National Laboratory, which is supported by the Office of Science, Office of Basic Energy Sciences, U.S. Department of Energy, under Contract No. DE-AC02-05CH11231. Special Core Analysis Laboratories, Inc. conducted the mercury injection experiments mentioned in this study.
- Capillary pressure
- Pore-scale modeling
- Two-phase flow
ASJC Scopus subject areas
- Chemical Engineering(all)