Fluid phase equilibria of Brazilian presalt crude oil – CO2 systems at high pressure and high temperature.

This paper aims to conduct an experimental investigation of the fluid phase behavior of a highly opaque Brazilian pre-salt crude oil-CO 2 system, specifically focusing on the occurrence of highly dispersed liquid-liquid transitions. The study involves examining the phase behavior of five global mole compositions [ z C O 2 = (37.9, 50.0, 76.6, 80.6, and 84.2) mol%] by using conventional PVT techniques as light scattering, pressure-volume curve, and direct fluid observation through sapphire windows. When other techniques were ineffective, a high-pressure microscope coupled with a short-wave infrared apparatus (SWIR camera and light source) was used for complex fluid inspection. [Display omitted] • Experimental measurements LV, LL, and SLL phase equilibria are presented. • 4 isopleth phase diagrams for Brazilian pre-salt crude oil + CO 2 are present. • Liquid-liquid equilibrium undetected by NIR transmittance signal. • Fluid inspection using short wave infrared coupled in high pressure microscope. [ABSTRACT FROM AUTHOR]