Modelagem do comportamento de fases e propriedades volumétricas dos fluidos de reservatório de petróleo utilizando equações de estado cúbicas e não-cúbicas

Abstract

Reservoir simulators are widely used in petroleum engineering projects. The simulators of compositional type using equations of state (EOS’s) for calculate various properties of petroleum fluids, as such the density of oil phase, the compressibility factor of gas phase, the saturation pressure, etc. In this work was studied the predictive capacity of three EOS’s, two cubic and widely used in reservoir simulators (Soave- Redlich-Kwong and Peng-Robinson) and a non-cubic EOS, that has had notoriety and comes of statistical mechanics, the Perturbed Chain – Statistical Association Fluid Theory (PC-SAFT). Several data from literature were collected and modeled with these EOS’s. A simulator in object-oriented language (Delphi 7®) for calculations of liquid-vapor equilibrium and volumetric properties of petroleum fluids was developed during this work. The EOS’s present good results for some properties, such as relative volume,compressibility factor and oil density. Even the PC-SAFT EOS present similar results when compared with other EOS’s studied, much can be still improved in this equation for applications in reservoir simulators, since it contain few studies on this type of application.