A non conventional enhanced oil recovery technique is proposed for recovering oil from an Alaskan tar sand reservoir. This technique involves the use of electromagnetic heating with horizontal wells along with water injection, gas injection or primary depletion. This technique eliminates one of the bigger technical problems with conventional steam injection in the North Slope area. The existence of a large permafrost region in North Slope reduces the effective heat that can be transmitted to a reservoir, even with insulated tubing. Applying the heat with a downhole device, such as electromagnetic heating is a much more efficient process than conventional thermal recovery techniques. The presence of horizontal well allows one to eliminate the problem of small heating radius and large area may be conducted even when the heating radius is small. Also, a horizontal well, particularly one located at the bottom of a thick sand with vertical permeability, allows gravity drainage of a much larger reservoir volume. This paper presents numerical simulation results of such a process for Alaskan tar sand reservoirs using a horizontal well simulator. Various options, such as gas injection, waterflooding, etc. are investigated along with electromagnetic heating. Numerical simulation results show oil recovery as high as 60% of the oil in place for tar sands. The recovery is even higher for heavy oil of moderate viscosity. Finally, a numerical run using steam-assisted gravity drainage is conducted for comparison. The new scheme presented in this paper showed much higher efficiency than the steam-assisted gravity drainage process.

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