Comparison of an Improved Compositional Micellar/Polymer Simulator With Laboratory Corefloods

Abstract

SummaryIn this paper, we compare numerical simulations made with our previously reported simulator with both our own and literature experiments. The most significant improvement concerns the phase behavior model used in the simulator. The new model approximately represents the phase behavior of pseudoquaternary mixtures containing surfactant, cosurfactant, oil, and brine. The different effects of sodium and calcium cations in the mixtures are accounted for with a new cation exchange model allowing for exchange with both clays and micelles. A tertiary oilflood experiment is reported that includes a more complete analysis of phase compositions and properties than generally available previously. Produced samples were analyzed for surfactant, alcohol, sodium, calcium, polymer, tritium, water, carbon-14-tagged decane, and decane. These analyses and pressure drop were compared with simulated behavior. Supporting physical property data were used as much as possible to estimate simulator input parameters rather than adjusting or "history matching" the results. Agreement with the most important features of the experiment was good. This agreement and good agreement with an experiment from the literature lead us to conclude that a significant improvement over previous efforts has been achieved. Especially noteworthy is our capability to account for the chromatographic separation of surfactant and alcohol.