Abstract
In preparation for a field pilot of cyclic solvent injection (CSI) on two depleted cold heavy oil production with sand (CHOPS) wells, a series of oilsands coreflood experiments were conducted to evaluate the effectiveness of various commercially available solvents and make a solvent recommendation for the pilot. Oil recovery and solvent recovery were the key performance indicators used to compare CSI effectiveness of each solvent blend. The operating pressure for each test was kept relatively constant for each solvent blend tested. Tested solvents included blends of methane/propane, carbon dioxide/propane, methane/ethane, 100% ethane, and nitrogen. Sensitivities for depletion rate and blowdown pressure are also presented. Overall the 100% ethane test performed the best with the highest oil recovery and solvent recovery in the fewest cycles. Due to the lack of commercial ethane supply and the industry experience with methane/propane in Husky Edam’s CSI pilot, a methane/propane blend was recommended for the field pilot in Manatokan East near Bonnyville Alberta Canada.
