Simulation Study of Surfactant Flooding Process in an Iranian Fractured Oil Reservoir

摘要

Huge amount of oil remains in the reservoirs after primary and secondary oil recovery, especially if the reservoirs are fractured and oil wet. Surfactant flooding is regarded as the most efficient Enhanced Oil Recovery (EOR) method if the economical factors are studied. Concerns over fossil energy shortage for the next decade, leads to the idea of using this method to potentially production of 84 billion barrels of oil in the Iranian oil reserve alone. In this study the simulation of surfactant flooding in one of the Iranian oil reservoirs has been performed.This fractured oil reservoir is a giant structure which is located in southwest of Iran with about 28 billion barrels of initial oil in place. Matrix permeability and porosity are in the range of 0.0922-119.20 md and 8-19 percent respectively.At first surfactant imbibition experimental data is utilized to investigate the role of important parameters in surfactant flooding such as surfactant critical micelle concentration (cmc), molecular diffusion, and capillary number, then by using the results of first part, simulation of surfactant flooding on a sector model of this carbonate reservoir has been performed and has been compared with conventional water flooding. Besides, sensitivity analysis has been done to study the effects of important parameters during surfactant flooding.Results show that Surfactant flooding process respect to water injection likely to be profitable for this reservoir and would improve oil recovery factor to nearly 14%; finally the operational parameters including time of starting project, injection well location, injection rates, surfactant concentration have been optimized for this reservoir.