The Effect of Stratification, Fractures, and Dip on Steam Sweep Efficiency and Heat Requirements of Steamflood Operations

Abstract

ABSTRACT A one-phase, thermal simulator has been utilized to study the applicability of steamflooding in different reservoir geometries. Two and three-dimensional numerical models of homogeneous dipping (0°, 15°, 30°, 45°, and 60°), heterogeneous dipping (0°, 30°, and 45°), and fractured dipping (0°, 30°, and 45°) reservoirs have been developed. The parameters investigated were heat utilization, steam vertical and areal sweep efficiency. The simulator was also utilized to generate temperature profiles for different reservoir types at different injection times. Results of this study show that dip and/or fractures should not be considered detrimental when screening reservoirs for steamflooding. Heat utilization and vertical sweep efficiency are not significantly affected by dip. Formation heterogeneities tend to control steam displacement in a reservoir more-so than dip does. Natural or induced fractures improved the steam sweep efficiency but at the expense of heat utilization. Averaged (over the upper, middle, and lower section of the reservoir) steam areal sweep efficiency improves with dip and/or fractures, and for extended injection periods the observed differences become less significant.