Perpustakaan Digital ITB

One of the reservoir problems which need special Enhanced Oil Recovery (EOR) treatment is the existence of heavy oil. Heavy oil is part of certain petroleum reservoir fluid. Its high viscosity makes oil impossible to flow for natural flowing, because the viscosity of heavy oil may reach 1000 cp. Historically, thermal recovery processes have been aimed at viscous oil in shallow reservoir. Thermal recovery has been proven as the most effective method to solve this problem since early 1931-1932 in USA. Steamflooding is one of the thermal recovery methods which is mostly used in the world. It has high displacement efficiency which can recover up to 60% of IOIP. The method lies on the basis that the steam is injected into the reservoir, heating the oil, and displacing the oil. The heating makes the heavy oil less viscou and easier to flow. and easier to flow. This paper will analyze the effects of combination of steamflood with other EOR methods in X-WBW field, one of the largest oilfields in Indonesia. The other EOR methods which are attempted to be combined are CO2 injection, N2 injection, and Cyclic Steam Injection. Analyses are based on the result of thermal simulation using CMGTM STAR simulation software. From the analyses, we may conclude that gas injection (CO2 and N2) is not a recommended treatment applied to increase oil production in high viscosity oil and low pressure reservoir as X-WBW field. Thermal recovery is still the most effective method where the recovery factor from combination of steamflood and cyclic steam stimulation simultaneously may reach over 82% of IOIP.