CO2 Wettability of the Mt. Simon Sandstone and Implications for Predicting Pore Scale Transport

Abstract:

Geological sequestration of CO2 is an emerging technology for mitigating atmospheric accumulation of CO2. A large demonstration of this technology was performed in the Illinois Basin under the direction of the Midwest Geological Sequestration Consortium. A key challenge is predicting the migration pathways of CO2 in the Mt. Simon Sandstone of the Illinois Basin, which is a function of reservoir permeability and wettability. The primary goal of this effort is to measure the CO2 wettability of rock samples from the Mt. Simon Sandstone, and to determine how this wettability is affected by the different mineral components comprising the samples. Contact angle measurements of CO2 in brine on pure minerals present in the Mt. Simon sandstone, and on the Mt. Simon sandstone itself, will be presented. The effects of surface roughness and surface charge of the samples on contact angle will also be presented. Implications of the results on predicting wettability in real reservoirs will be discussed, as well as the effects of wettability on predicting the migration of CO2 at the pore scale.