CO2 storage capacity predictions for Weyburn CO2-EOR project

Abstract

The objective of Weyburn CO2-EOR multidisciplinary project is to conduct reservoir simulation to predict the movement of CO2 front, the distribution of CO2, and the storage capacity of CO2 in the Weyburn reservoir. These reservoir simulation predictions provide important information for the risk assessment of potential CO2 leakage and migration. CO2 is injected into the Weybum oilfield in southeastern Saskatchewan, one of the largest medium gravity crude oil fields in Canada, for the purpose of enhanced oil recovery (EOR) by EnCana Corporation, while at the same time this site is being studied for the feasibility of geological storage of CO2, a greenhouse gas (GHG). This study is a part of the “IEA Weybum CO2 Monitoring and Storage Project” that describes the predictions of the CO2 storage capacity in the entire 75 CO2-EOR patterns in the Weyburn field using reservoir model as a tool. The capability of the reservoir model is to simulate the CO2-EOR process that is first validated based on three very detailed simulations by matching of pre-CO2 and up-to-date post-CO2 field production history in three selected single patterns in the 19-pattern Phase 1A area and followed by predictions for the CO2 distribution and storage performance at the end of the EOR. The three coarse-grid single-pattern simulations are used as building blocks to carry out simulations of the entire 75 patterns as the same grid resolution is applied.