Numerical Modeling of CO2 Sequestration in Geologic Formations -Recent Results and Open Challenges
Abstract
Rising atmospheric concentrations of CO2, and their role inglobal warming, have prompted efforts to reduce emissions of CO2 fromburning of fossil fuels. An attractive mitigation option underconsideration in many countries is the injection of CO2 from stationarysources, such as fossil-fueled power plants, into deep, stable geologicformations, where it would be stored and kept out of the atmosphere fortime periods of hundreds to thousands of years or more. Potentialgeologic storage reservoirs include depleted or depleting oil and gasreservoirs, unmineable coal seams, and saline formations. While oil andgas reservoirs may provide some attractive early targets for CO2 storage,estimates for geographic regions worldwide have suggested that onlysaline formations would provide sufficient storage capacity tosubstantially impact atmospheric releases. This paper will focus on CO2storage in saline formations.Injection of CO2 into a saline aquifer willgive rise to immiscible displacement of brine by the advancing CO2. Thelower viscosity of CO2 relative to aqueous fluids provides a potentialfor hydrodynamic instabilities during the displacement process. Attypical subsurface conditions of temperature and pressure, CO2 is lessdense than aqueous fluids and is subject to upward buoyancy force inenvironments where pressures are controlled by an ambient aqueous phase.Thus CO2 would tend to rise towards the top of a permeable formation andaccumulatemore »
- Authors:
- Publication Date:
- Research Org.:
- Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
- Sponsoring Org.:
- USDOE. Assistant Secretary for Fossil Energy.Coal
- OSTI Identifier:
- 919767
- Report Number(s):
- LBNL-59888
R&D Project: G22401; BnR: AA1505000; TRN: US200822%%531
- DOE Contract Number:
- DE-AC02-05CH11231
- Resource Type:
- Conference
- Resource Relation:
- Conference: Computational Methods in Water Resources (CMWRXVI), Copenhagen, Denmark, 18-22 June 2006
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 54 ENVIRONMENTAL SCIENCES; CARBON DIOXIDE; CHEMICAL REACTIONS; COAL SEAMS; FOSSIL FUELS; GEOLOGIC FORMATIONS; GREENHOUSE EFFECT; INTERSTITIAL WATER; POWER PLANTS; STORAGE; WATER RESOURCES; CARBON SEQUESTRATION
Citation Formats
Pruess, Karsten. Numerical Modeling of CO2 Sequestration in Geologic Formations -Recent Results and Open Challenges. United States: N. p., 2006.
Web.
Pruess, Karsten. Numerical Modeling of CO2 Sequestration in Geologic Formations -Recent Results and Open Challenges. United States.
Pruess, Karsten. Wed .
"Numerical Modeling of CO2 Sequestration in Geologic Formations -Recent Results and Open Challenges". United States.
doi:. https://www.osti.gov/servlets/purl/919767.
@article{osti_919767,
title = {Numerical Modeling of CO2 Sequestration in Geologic Formations -Recent Results and Open Challenges},
author = {Pruess, Karsten},
abstractNote = {Rising atmospheric concentrations of CO2, and their role inglobal warming, have prompted efforts to reduce emissions of CO2 fromburning of fossil fuels. An attractive mitigation option underconsideration in many countries is the injection of CO2 from stationarysources, such as fossil-fueled power plants, into deep, stable geologicformations, where it would be stored and kept out of the atmosphere fortime periods of hundreds to thousands of years or more. Potentialgeologic storage reservoirs include depleted or depleting oil and gasreservoirs, unmineable coal seams, and saline formations. While oil andgas reservoirs may provide some attractive early targets for CO2 storage,estimates for geographic regions worldwide have suggested that onlysaline formations would provide sufficient storage capacity tosubstantially impact atmospheric releases. This paper will focus on CO2storage in saline formations.Injection of CO2 into a saline aquifer willgive rise to immiscible displacement of brine by the advancing CO2. Thelower viscosity of CO2 relative to aqueous fluids provides a potentialfor hydrodynamic instabilities during the displacement process. Attypical subsurface conditions of temperature and pressure, CO2 is lessdense than aqueous fluids and is subject to upward buoyancy force inenvironments where pressures are controlled by an ambient aqueous phase.Thus CO2 would tend to rise towards the top of a permeable formation andaccumulate beneath the caprock. Some CO2 will also dissolve in theaqueous phase, while the CO2-rich phase may dissolve some formationwaters, which would tend to dry out the vicinity of the injection wells.CO2 will make formation waters more acidic, and will induce chemicalrections that may precipitate and dissolve mineral phases (Xu et al.,2004). As a consequence of CO2 injection, significant pressurization offormation fluids would occur over large areas. These pressurizationeffects will change effective stresses, and may cause movement alongfaults with associated seismicity and increases in permeability thatcould lead to leakage from the storage reservoir (Rutqvist and Tsang,2005).},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Mar 08 00:00:00 EST 2006},
month = {Wed Mar 08 00:00:00 EST 2006}
}
-
PFLOTRAN a massively parallel computer code for modeling coupled hydro-thermal-chemical processes in variably saturated, non-isothermal porous media is applied to sequestration of supercritical CO{sub 2} in deep geologic formations. Two different methods of solution to the governing partial differential equations are implemented referred to as variable switching and the flash approach. Variable switching entails choosing the independent variables according to the set of phases present in a control volume, whereas in the flash approach a persistent set of variables are used through the calculation. The features and performance of the two approaches are described and contrasted in regard to stabilitymore »
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Modeling the effects of topography and wind on atmospheric dispersion of CO2 surface leakage at geologic carbon sequestration sites
Understanding the potential impacts of unexpected surface releases of CO{sub 2} is an essential part of risk assessment for geologic carbon sequestration sites. We have extended a mesoscale atmospheric model to model dense gas dispersion of CO{sub 2} leakage. The hazard from CO{sub 2} leakage is greatest in regions with topographic depressions where the dense gas can pool. Simulation of dispersion in idealized topographies shows that CO{sub 2} can persist even under high winds. Simulation of a variety of topographies, winds, and release conditions allows the generation of a catalog of simulation results that can be queried to estimate potentialmore » -
Supercritical fluid behavior at nanoscale interfaces: implications for CO2 sequestration in geologic formations
Injection of CO2 into subsurface geologic formations has been identified as a key strategy for mitigating the impact of anthropogenic emissions of CO2. A key aspect of this process is the prevention of leakage from the host formation by an effective cap or seal rock which has low porosity and permeability characteristics. Shales comprise the majority of cap rocks encountered in subsurface injection sites with pore sizes typically less than 100 nm and whose surface chemistries are dominated by quartz (SiO2) and clays. We report the behavior of pure CO2 interacting with simple substrates, i.e. SiO2 and mica, that actmore »