Security of Storage in Carbon Dioxide Enhanced Oil Recovery

The Pembina Cardium CO₂ Monitoring Pilot was used as a test site to determine the relative roles of trapping mechanisms. Two methods to assess this distribution are presented. A geochemical approach using empirical data from the site was used to determine the phase distribution of CO₂ at a number of production wells that were sampled monthly during a two-year CO₂ injection pilot. In addition, a simplified reservoir simulation was performed. Results indicate that significant amounts of CO₂ are stored in the oil phase thus reducing the amount of CO₂ available as a buoyant free phase and hence increasing storage security.