Enhanced Oil Recovery Using CO 2 in Alaska

• Published in: Geosciences
• Main Authors: Banabas Dogah, Vahid Atashbari, Mohabbat Ahmadi, Brent Sheets
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2021
• Subjects: CO 2; carbon dioxide; enhanced oil recovery; Alaska; heavy oil; viscous oil; Geology; QE1-996.5; permafrost
• Online Access: https://doi.org/10.3390/geosciences11020098; https://doaj.org/article/aa3f69876e6b48f2b74afeb61a265554

Alaska holds more than 68 billion barrels of proved oil reserves and more than 36.7 trillion cubic feet of proved natural gas reserves with some special conditions such as proximity to permafrost, making Alaskan petroleum reserves unique. The low temperature in shallow reservoirs prohibited hydrocarbons’ ideal maturation, thereby generating several heavy and viscous oil accumulations in this state. This also limits the enhanced oil recovery (EOR) options, leaving the thermal methods off the table to avoid permafrost thawing, which can cause wellbore collapse. Several solutions have been attempted for improving oil production from heavy and viscous oil in Alaska; however, they have not yielded the desired recovery, and ultimate recovery factors are still less than the global average. One solution identified as a better alternative is using CO 2 as an injecting fluid, alternated by water or mixed with other injectants. This paper provides a comprehensive overview of all studies on using CO 2 for enhanced oil recovery purposes in Alaska and highlights common and unique challenges this approach may face. The suitability of CO 2 -EOR methods in the Alaskan oil pools is examined, and a ranking of the oil pools with publicly available data is provided.