Numerical modelling of the effect of wettability, interfacial tension and temperature on oil recovery at pore-scale level.

Iyi, Draco; Balogun, Yakubu; Oyeneyin, Babs; Faisal, Nadimul

Abstract

A numerical investigation into the effect of wettability and temperature on oil recovery with a hot water injection at different temperatures is reported in this paper. The computational domain is a two-dimensional porous medium (reservoir) maintained at a fixed temperature with pore spaces of varying sizes and interconnected pore-throats. ANSYS-Fluent VOF (volume of fluid) model was used to simulate the two-phase transport through the reservoir with hot water injections at varying temperatures (20, 40 and 60 °C) and wettability contact angles of 45°, 90° and 150°. In addition, an investigation was conducted on the effect of combined interfacial tension and matrix wettability on oil recovery process at low and high interfacial tension of 0.025 N/m and 0.045 N/m respectively for the three different wettability contact angles. The results showed that, the displacement behaviour of water and oil-wet system is affected significantly by the contact angle with a profound effect on the oil recovery factor. In the water-wet case (with the water wetting the matrix wall and the oil phase surrounded by water), relatively more oil is displaced from the domain thereby improving the oil recovery factor. The water-wetter system resulted in about 35–45% oil recovery than the oil-wet system, with the unrecovered oil mainly adhering to the wall region of the pore bodies for oil-wet system. For the intermediate wet case, initial fluid distribution is seen to have a more significant effect on the displacement behaviour than the contact angles. In conclusion, by altering the wettability from oil-wet to water-wet condition, the oil recovery rate is improved. The results from this study are consistent with the experimental and numerical studies in literature and it will further enhance the understanding of the phenomenon that is critical to the mechanism of recovery such as surfactant and polymer flooding process.

Citation

IYI, D., BALOGUN, Y., OYENEYIN, B. and FAISAL, N. 2021. Numerical modelling of the effect of wettability, interfacial tension and temperature on oil recovery at pore-scale level. Journal of petroleum science and engineering [online], 201, article ID 108453. Available from: https://doi.org/10.1016/j.petrol.2021.108453

• Journal Article Type: Article
• Acceptance Date: Jan 21, 2021
• Online Publication Date: Feb 4, 2021
• Publication Date: Jun 30, 2021
• Deposit Date: Feb 11, 2021
• Publicly Available Date: Feb 5, 2022
• Journal: Journal of petroleum science and engineering
• Print ISSN: 0920-4105
• Electronic ISSN: 1873-4715
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 201
• Article Number: 108453
• DOI: https://doi.org/10.1016/j.petrol.2021.108453
• Keywords: Oil recovery; Wettability; Interfacial tension; Temperature; Contact angle; Computational fluid dynamics
• Public URL: https://rgu-repository.worktribe.com/output/1187381