Uncertainty Quantification of Sequestrated CO2 in CCUS project
Wei Jia and Brian McPherson
University of Utah
CO2 sequestration can be achieved in the Enhanced Oil Recovery (EOR) process by many trapping mechanisms, including hydrodynamic trapping, residual trapping, and solution trapping. We evaluated the total amount of sequestrated CO2 and the role/importance of each trapping mechanism for a CCUS site. However, given the uncertainty of subsurface properties, such as permeability and porosity, uncertainty quantification (UQ) is necessary for estimating the amount of trapped CO2. As it is computationally expensive to follow the approach of Monte Carlo simulation and conventional geocellular simulation, we applied the Polynomial Chaos Expansion (PCE) methodology to reduce computation cost while still maintain accuracy. Geostatistics techniques were applied to generate stochastic realizations based on well logs and seismic survey. While small amount of realizations were simulated with conventional geocellular simulator to develop reduced order models (ROMs) by applying PCE methodology, rest realizations were simulated through the established ROMs to generate probability distribution function (PDF) of the amount of sequestrated CO2. Our results suggest that while the role of each trapping mechanism is not affected by parameter uncertainty, the uncertainty of the amount of trapped CO2 cannot be neglected and must be taken into consideration.
AAPG Search and Discovery Article #90169©2013 AAPG Rocky Mountain Section 62nd Annual Meeting, Salt Lake City, Utah, September 22-24, 2013