Effect of wettability alteration on long-term behavior of fluids in subsurface

Journal Article · Wed Jan 13 04:00:00 EST 2016 · Computational Particle Mechanics

DOI:https://doi.org/10.1007/s40571-015-0098-8· OSTI ID:1333991

Bandara, Uditha C.; Palmer, Bruce J.; Tartakovsky, Alexandre M.

Wettability is an important factor affecting fluid behavior in the subsurface, including oil, gas, and supercritical CO$$_2$$ in deep geological reservoirs. For example, CO$$_2$$ is generally assumed to behave as a non-wetting fluid, which favors safe storage. However, because of chemical heterogeneity of the reservoirs, mixed wettability conditions can exist. Furthermore, recent experiments suggest that with time, the wettability of super-critical CO$$_2$$ may change from non-wetting to partially-wetting due to changes in electrostatic interactions. These changes are caused by chemical reactions between dissolved CO$$_2$$ and its environment. To date, the effect of wettability alteration and mixed wettability on the long term fate of injected CO$$_2$$ has not well been studied. Here, we use the multiphase Pairwise Force Smoothed Particle Hydrodynamics (PF-SPH) Model to study complex pore-scale processes involved in geological CO$$_2$$ sequestration, including the effect of spatial and temporal wettability variations on long-term distribution of CO$$_2$$ in porous media. Results reveal that in the absence of dissolution of supercritical CO$$_2$$ and precipitation of carbonate minerals (mineral trapping), the amount of trapped supercritical CO$$_2$$ significantly decreases as the wettability of the porous media changes from brine-wet to partial-wet or CO$$_2$$-wet.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1333991
• Report Number(s): PNNL-SA-90182
• Journal Information: Computational Particle Mechanics, Journal Name: Computational Particle Mechanics Journal Issue: 2 Vol. 3; ISSN 2196-4378
• Country of Publication: United States
• Language: English

Related Subjects

CO2 sequestration
Pore-scale modeling
Smoothed Particle Hydrodynamics
Wettability alteration