Previous Group Members
J.A. Becker (Cambridge), S. Lyle (Birmingham), N. Assayag (Cambridge)
B.W.D. Yardley (Leeds), C.J. Ballentine (Manchester), A. Masters (Manchester), C Rochelle (BGS), Jonathan Pearce (BGS)
Carbon Capture and Storage (CCS), also known as carbon sequestration, involves the separation of CO2 from power station fuels or waste gases, injection and subsequent trapping of the CO2 underground in geological formations. Carbon sequestration offers one of the more economical and practical mitigation measures to reduce global anthropogenic CO2 emissions to the atmosphere. A key aspect of carbon sequestration is the need to ensure that the storage is safe and efficient and this necessitates the need to model the fate of the CO2 over the ~10 000 year storage period.
Carbon capture has the potential to reduce more than 90 percent of an individual power plant's carbon emissions. Stationary facilities that burn fossil fuels – such as power plants or cement factories – are candidates for the technology, especially as power plants comprise 40 percent of the world's fossil fuel-derived carbon emissions.
Imaging and Modelling of CO2 Flows
In conjunction with Herbert Huppert (Institute of Theoretical Geophysics) we are investigating the multi-phase flow of CO2 and brines in reservoirs based on seismic images of the Sleipner Field. We are also using natural CO2 reservoirs to better understand the fate of CO2 stored for long periods in geological reservoirs.
Analogue Studies: ‘Predicting the fate of CO2 in geological reservoirs for modelling geological carbon storage’Carbon dioxide injected into geological formations dissolves in water/brine to form a slightly denser CO2-charged fluid. Over short timescales (years) this fluid reacts with carbonate and silicate minerals in the reservoir. On longer timescales the fluids are predicted to precipitate a significant fraction of the CO2 as carbonate minerals. Both the dissolution of CO2 in formation brines and the precipitation of carbonate minerals should act to retain CO2 in the reservoirs. Our research focuses on the assessment of fluid-mineral reaction kinetics in order to better understand the timescales and properties of the reactions which may control precipitation of carbonate minerals, or conversely, degrade caprocks and lead to leakage of CO2. To date, published modelling of mineral reactions in CO2 reservoirs uses laboratory determinations of mineral-fluid reaction rates. It is well known that rates measured in the laboratory tend to be faster, often by orders of magnitude, than rates measured in field settings. We therefore are using natural CO2 degassing systems in Utah, Arizona and Colorado in the US to study fluid-mineral reactions and their effects on reservoir characteristics. Analyses of drill core, fluids, gases from seeps and drill holes into existing CO2 reservoirs and study of fossil CO2 reservoirs are being combined with thermodynamic modelling of fluid-mineral reactions to better understand the nature and rates of the reactions in the natural reservoirs.
The research is carried out in collaboration with The NERC Carbon Capture and Storage Consortium and the EU GRASP Marie Curie and a new NERC Consortium Project. The latter, which starts in 2008, is a collaboration between Mike Bickle and Albert Galy (Cambridge), Bruce Yardley (Leeds), Chris Rochelle and Jonathan Pearce (British Geological Survey) and Chris Ballentine and Andrew Masters (Manchester).
Publications From This Work
- Bickle, M., Chadwick, A., Huppert, H. E., Hallworth, M., and Lyle, S., 2007, Modelling carbon dioxide accumulation at Sleipner: Implications for underground carbon storage: Earth and Planetary Science Letters, v. 255, p. 164–176.
- Lyle, S., Huppert, H. E., Hallworth, M., Bickle, M., and Chadwick, A., 2005, Axisymmetric gravity currents in a porous medium: J. Fluid Mech., v. 543, p. 293-302.
Last updated on 19-Jan-10 15:27