Journal article
Real Time 3D Observations of Portland Cement Carbonation at CO2 Storage Conditions
Norwegian University of Science and Technology1
University of Oslo2
SINTEF3
Lawrence Livermore National Laboratory4
University of Copenhagen5
Department of Physics, Technical University of Denmark6
Neutrons and X-rays for Materials Physics, Department of Physics, Technical University of Denmark7
Monash University8
CNRS9
Depleted oil reservoirs are considered a viable solution to the global challenge of CO2 storage. A key concern is whether the wells can be suitably sealed with cement to hinder the escape of CO2. Under reservoir conditions, CO2 is in its supercritical state, and the high pressures and temperatures involved make real-time microscopic observations of cement degradation experimentally challenging.
Here, we present an in situ 3D dynamic X-ray micro computed tomography (μ-CT) study of well cement carbonation at realistic reservoir stress, pore-pressure, and temperature conditions. The high-resolution time-lapse 3D images allow monitoring the progress of reaction fronts in Portland cement, including density changes, sample deformation, and mineral precipitation and dissolution.
By switching between flow and nonflow conditions of CO2-saturated water through cement, we were able to delineate regimes dominated by calcium carbonate precipitation and dissolution. For the first time, we demonstrate experimentally the impact of the flow history on CO2 leakage risk for cement plugging.
In-situ μ-CT experiments combined with geochemical modeling provide unique insight into the interactions between CO2 and cement, potentially helping in assessing the risks of CO2 storage in geological reservoirs.
Language: | English |
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Publisher: | American Chemical Society |
Year: | 2020 |
Pages: | 8323-8332 |
ISSN: | 15205851 and 0013936x |
Types: | Journal article |
DOI: | 10.1021/acs.est.0c00578 |
ORCIDs: | Sørensen, Henning Osholm , 0000-0003-3732-356X , 0000-0002-1154-3030 , 0000-0002-6456-3318 , 0000-0002-0023-681X and 0000-0002-5125-5930 |