Study of Mass Transfer and Sorption Phenomena in CO2/Brine/Rock Systems

Geological sequestration of CO₂ is a promising technique to reduce the emissions of greenhouse gases and to mitigate global warming. Understanding of mass transfer and sorption characteristics of CO₂ in relevant brines, and in brine-saturated reservoir rock samples at realistic reservoir conditions is considered essential for predicting the gas distribution after injection, and for potentially estimating the cumulative amount of trapped gas. In this study, Mount Simon cores from Illinois Basin were characterized via measurements of their porosity and permeability. Their internal surface area and pore size distribution were also measured via probe-gas sorption experiments using two different gases ( N₂ at 77 K and CO₂ at 195 K) in order to provide additional information about the microstructure of the cores. A series of high-pressure core flooding experiments were conducted to understand interactions between core, brine and CO₂ in terms of sorption, mass transfer and displacement characteristics. In addition, mathematical models are developed to describe the observed mass transfer and sorption behavior at the core-scale.