The effect of chemically enhanced oil recovery on thin oil rim reservoirs

• Published in: Journal of petroleum exploration and production technology Vol. 11; no. 3; pp. 1461 - 1474
• Main Authors: Olabode, O. A., Ogbebor, V. O., Onyeka, E. O., Felix, B. C.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-03-2021; Springer Nature B.V; SpringerOpen
• Subjects: And concurrent production; Aquifers; Chemical enhanced oil recovery; Earth and Environmental Science; Earth Sciences; Energy Systems; Enhanced oil recovery; Gas injection; Geology; Industrial and Production Engineering; Industrial Chemistry/Chemical Engineering; Injection; Monitoring/Environmental Analysis; Offshore Engineering; Oil production; Oil recovery; Oil rims; Original Paper-Production Geophysics; Reservoirs; Simulators; Solar eclipses; Surfactants; Chemical enhanced oil recovery; Surfactants; And concurrent production; Oil rims
• ISSN: 2190-0558; 2190-0566
• DOI: 10.1007/s13202-021-01090-9

Oil rim reservoirs are characterised with a small thickness relative to their overlying gas caps and underlying aquifers and the development these reservoirs are planned very carefully in order to avoid gas and water coning and maximise oil production. Studies have shown low oil recoveries from water and gas injection, and while foam and water alternating gas injections resulted in positive recoveries, it is viewed that an option of an application of chemical enhanced oil recovery option would be preferable. This paper focuses on the application of chemical enhanced oil recovery to improve production from an oil rim reservoir in Niger Delta. Using Eclipse black oil simulator, the effects of surfactant concentration and injection time and surfactant alternating gas are studied on overall oil recovery. Surfactant injections at start and middle of production resulted in a 3.7 MMstb and 3.6 MMstb at surfactant concentration of 1% vol, respectively. This amounted to a 6.6% and 6.5% increment over the base case of no injection. A case study of surfactant alternating gas at the middle of production gave an oil recovery estimate of 10.7%.