Developing New PVT Correlations for the Libyan Crude Oil Using Samples from Different Reservoirs

Five PVT correlation include bubble point pressure, solution gas oil ratio, oil formation volume factor, dead oil viscosity and oil density were used to analyze a total of 102 data sets from the Libyan crude oil reservoirs representing Sirte, Ghdames, Murzug and offshore Tripolitania basins, to find anew more accurate correlations. Linear & nonlinear regression and statistical software package (Excel, Minitab and Mat lab software) were applied on the above -mentioned crude samples. The application of multilinear regression and a statically software on the solution gas, oil ratio, temperature and API gravity, exhibit a direct proportional with the bubble point, where as in the case of gas gravity the correlation show inversely proportional with the bubble point. The relationships between the solution gas oil and other properties show that the distribution of the tested points in these investigations are located very closet the 45° trend line for the solution gas oil ratio, indicating that the correlations have a higher accuracy with our new developed PVT equations for the analyzed Libyan crude oil samples. The cross plots between measured vs. calculated oil formation factor, dead oil viscosity and oil density is play a very good reliable correlation compared with previous published correlations done by other researchers as well as in the statistical calculation, in addition the AARE and R2 results were calculated for previous published correlation in different locations over the world. Based on the obtained results in this research, the proposed correlations are more accurate than all the other previous published correlations, exclusively for the Libyan crude oil