Estimating the PVT Properties for Crude Oil from a Southern Iraqi Oil Field

Abstract

The PVT properties of crude oil are important to calculations of production and reservoir performance. These properties can be determined in the laboratory at specified conditions of pressure and temperature. To estimate PVT fluid properties at a wider range of conditions of pressure and temperature, an empirical correlation should be used where there are no laboratory measurements. These empirical correlations can, however, only be used after making the appropriate adjustments to the specified crude oil samples. In this study, the data from laboratory measurements of the PVT properties for five oil samples were used. These five samples were collected from different wells within the Luhais oil field. The measurements were taken at reservoir conditions with slight differences from one sample to another. The five samples were then adjusted to the empirical correlations and the saturation pressure determined. The resulting models of the samples after adjustment were combined to estimate a generalised model of the fluid properties that represented the properties of the studied crude oil. The properties of formation volume factor, gas oil-ratio, and viscosity with respect to pressure at reservoir temperature, assumed to be 185 °F, are thus presented in this paper.