The expediency of remote location from an injection well of water shut-off material in a high-permeability sublayer

The paper investigates the expediency of placement a water shut-off material in a high-permeability watered sublayer away from the injection well. This scenario of location the blocking agent with complex rheological properties in a reservoir requires reliable design and accurate control of execution, which significantly complicates the reservoir treatment process and, therefore, demands well-founded justification. The analysis of the impact of the viscosity ratio between the injected and produced fluids, as well the distance between the injection and production wells, on the effectiveness of shut-off measures was performed based on a series of multivariate simulations. The waterflooding process is simulated using g a high-speed computing two-dimensional model of stream tube with a computational block size of about 0.1 m. Applying of this a model allowed to reproduce small-scale hydrodynamic effects and the flow structure in the area of a relatively thin high-permeability sublayer and near the interval of its isolation with a high degree of detail. The fundamental dynamic structures of the waterflooding areas of the effective stream tube between the wells are introduced. The dependence of the optimal location from the injection well to the optimal location of the blocking material, which provides the maximum increase in oil recovery at a fixed level of water cut, on the variable parameters is revealed. A hydrodynamic analysis of various modes of waterflooding of the inter-well area of the formation is presented. This analysis simplifies the prediction and decision-making on the advisability of a remote location of the blocking material for a given ratio of phase viscosity and distance between wells.