Optimization of Drainage-Area Configurations To Maximize Recovery From SAGD Operations

Abstract

Summary Placement of steam-assisted-gravity-drainage (SAGD) surface production pads and subsurface drainage areas in the McMurray formation to maximize the economic potential of an area is a challenging problem. The location of surface pads (SPs) and drainage areas has a large impact on their production performance because of several factors, including variation of bitumen in place, variation of the reservoir base surface, vertical conformance, areal conformance, interaction between different drainage areas and pads, and surface hazards. An optimization algorithm is presented to determine the positions and orientations of SPs and drainage areas over a reservoir area; therefore, the potential for economically recoverable bitumen is maximized. The optimization considers either a deterministic model of the relevant properties or multiple realizations to account for uncertainty. Optimization considers all drainage areas simultaneously to ensure joint optimality of an entire set. The algorithm is demonstrated using two realistic examples that show a significant improvement in potential recovery. The algorithm executes in a reasonable amount of computation time, considering the complexity of the problem.