DESIGN OF THE INJECTION STRATEGY IN EXPANDING-SOLVENT STEAM-ASSISTED GRAVITY DRAINAGE

Abstract

Steam-Assisted Gravity Drainage is effective at extracting oil from heavy oil and bitumen reservoirs. However, steam generation by natural gas combustion can render the process uneconomic. It has been suggested that addition of injected solvents improves oil rates or at least maintains similar oil rates with reduced steam. This is the basis of the Expanding Solvent - Steam Assisted Gravity Drainage process. The central idea is that steam plus solvent is better than steam alone to recover heavy oil and bitumen. In this research, the steam and solvent injection strategy is designed by optimizing the cumulative steam-oil ratio by using simulated annealing and a commercial reservoir simulator.