Implementation of Ethyl Acetate as a Bio-Based Solvent for Bitumen Recovery

Abstract

Bitumen production from oilsands are more complicated than producing light oil from conventional reservoirs. Bitumen is not mobile at reservoir conditions and its viscosity should be reduced to be producible. Solvent assisted thermal recovery methods such as expanding solvent steam assisted gravity drainage (ES-SAGD) were introduced to improve the drawbacks of the current recovery methods such as steam assisted gravity drainage (SAGD) and cyclic steam stimulation (CSS). For the first time, Ethyl Acetate (EA) as a bio-based solvent is introduced to be implemented in ES-SAGD. Phase behavior measurements showed a significant reduction in density and viscosity of bitumen due to high solubility of ethyl acetate in bitumen. Numerical simulation studies and 2-D physical model sand-pack experiments revealed that co-injecting ethyl acetate with steam can noticeably increase the bitumen recovery and decrease the steam-oil-ratio, which can be translated to a significant energy savings and lower CO2 emissions.