Recharacterization of C7+ Fractions of Experimentally Recombined Oils using Lage’s Method and Perturbed Chain Statistical Associating Fluid Theory

Summary The recharacterization of C7+ fractions in experimentally recombined oils is crucial for accurately modeling reservoir fluids. This study applies Lage’s method to recharacterize C7+ fractions from two Brazilian pre-salt oils modeled with the perturbed chain statistical associating fluid theory (SAFT) (PC-SAFT) equation of state (EOS). After recombining the oil with gas, we analyzed the resulting sample using chromatographic techniques. The PC-SAFT model, combined with advanced algorithms for phase equilibrium calculations and critical point estimation, was used to predict the thermodynamic behavior of these complex fluids. Results demonstrate that Lage’s recharacterization method significantly reduces the number of pseudocomponents while maintaining accuracy in phase behavior and critical property predictions. This work highlights the potential of these methods in enhancing the accuracy and efficiency of thermodynamic modeling in the petroleum industry.