Study of Hydrocarbon Miscible Solvent Slug Injection Process for Improved Recovery of Heavy Oil From Schrader Bluff Pool, Milne Point Unit, Alaska. Annual Report, January 1, 1994--December 31, 1994

• Main Author: Sharma, G. D.
• Other Authors: United States. Department of Energy.
• Format: Report
• Language: English
• Published: University of Alaska Fairbanks 1995
• Subjects: Stratigraphy; 02 Petroleum; Miscible-Phase Displacement; Alaska; Progress Report; Petroleum; Optimization; Solvents; Reservoir Rock; Viscosity; Porosity; Milne Point; Alaska North Slope; north slope
• Online Access: https://doi.org/10.2172/83852; https://digital.library.unt.edu/ark:/67531/metadc788813/

Alaska is the second largest oil producing state in the nation and currently contributes nearly 24% of the nations oil production. It is imperative that Alaskan heavy oil fields be brought into production. Schrader Bluff reservoir, located in the Milne Point Unit, which is part of the heavy oil field known as West Sak is estimated to contain 1.5 billion barrels of (14 to 21 degree API) oil-in-place. The field is currently under production by primary depletion. The eventual implementation of enhanced oil recovery (EOR) techniques will be vital for the recovery of additional oil from this reservoir. The availability of hydrocarbon gases (solvents) on the Alaska North Slope make the hydrocarbon miscible solvent injection process an important consideration for the EOR project in Schrader Bluff reservoir. Since Schrader Bluff oil is heavy and viscous, a water-alternating-gas (WAG) type of process for oil recovery is appropriate since such a process tends to derive synergetic benefits from both water injection (which provides mobility control and improvement in sweep efficiency) and miscible gas injection (which provides improved displacement efficiency). A miscible solvent slug injection process rather than continuous solvent injection is considered appropriate. Slim tube displacement studies, PVT data and asphaltene precipitation studies are needed for Schrader bluff heavy oil to define possible hydrocarbon solvent suitable for miscible solvent slug displacement process. Coreflood experiments are also needed to determine the effect of solvent slug size, WAG ratio and solvent composition on the recovery and solvent breakthrough. A compositional reservoir simulation study will be conducted later to evaluate the complete performance of the hydrocarbon solvent slug process and to assess the feasibility of this process for improving recovery of heavy oil from Schrader Bluff reservoir.