Influence of Reservoir Properties on the Velocity of Water Movement from Injection to Production Well

Abstract

To maintain reservoir pressure, water is injected into oil reservoirs. In carbonate rock, water quickly breaks through fractures and highly permeable formations to production wells. This study analyzes the effect of the permeability, oil viscosity, pressure drop, and distance on the water velocity from an injection well to a production well. In the Tempest MORE hydrodynamic simulator (Roxar), a three-layer model of an oil reservoir was created, and water flow from an injection well to a production well was simulated with various values of the permeability, oil viscosity, and bottom hole pressure. The water velocity in the reservoir was estimated based on the mobility factor (k/µo). The results showed that at a mobility factor of less than 2 μm2/Pa s at a distance of 100 m in the reservoirs, the time of water migration from the injection well to the production well increased sharply, and at a mobility factor of more than 2 μm2/Pa s, it became shorter. An analysis of the time of water migration in fields with high-viscosity oil was conducted. The watering time turned out to be shorter than that predicted by the simulation. The permeability of the reservoir and the viscosity of the oil had the greatest influence on the water velocity. To a lesser extent, the time of water migration was affected by the distance between the wells and the difference in the bottomhole pressures. The average migration time for water with a mobility factor of more than 2 µm2/(Pa s) was 6.3 years. Based on the regression analysis of the field data, a linear equation for the time of water migration was obtained. The resulting equation makes it possible to predict the water cuts of wells and optimize oil production.