Reactive transport in the carbonate rock/water/CO2 system
PI: Dr Sam Krevor
Earth Sciences and Engineering
Geochemical processes, such as rock matrix dissolution, mineral precipitation, and inter-fluid mass transfer will have
important impacts on reservoir quality and storage integrity during the injection of CO2 into carbonate reservoirs. While
fundamental mineral/water chemical interactions are well described for simple crystals in the carbonate system, processes
involving chemical reaction and fluid flow through porous media are poorly understood. For example, even when
relevant reaction rate parameters, such as reactive surface area and mineralogy appear well constrained in the field,
discrepancies by a factor of 10^5 or more persist in estimated mineral reaction rates between field and laboratory
observations. This precludes accurate prediction of field-scale geochemical processes and presents a major challenge for
modeling CO2 sequestration in carbonate reservoirs.
This project will use core and pore-scale experiments and models to investigate the interplay of advective and diffusive
reactant transport, pore morphology, and mineralogical heterogeneity on chemical reactions during fluid flow through
reactive porous carbonate rocks. Specific goals of the project will be the development and use of experimental methods
and modeling for the characterization of reactive surface area, pore-scale fluid residence times, and observation of
chemical reaction during coreflooding experiments under varying conditions of fluid flow and chemical composition. An
ultimate goal of this work is to use these observations in the development of upscaling techniques for accurate and
efficient modeling of chemical processes during flow in porous media. The project will utilize results from ongoing
fundamental mineral dissolution and precipitation rate studies and state of the art laboratory facilities including ambient
and high-pressure coreflooding equipment, micro and medical x-ray CT scanners, and standard analysis equipment (mass
spectrometry, electron and confocal microscopy, ion chromatography, etc.).