Masoud Karimnezhad - Petroleum Engineering Department, Technical and Engineering Faculty, Shahid Bahonar University of Kerman, Iran
Amin Pajouhandeh - Young Researchers Society, Shahid Bahonar University of Kerman, Iran
Ali Kavosi - Young Researchers Society, Shahid Bahonar University of Kerman, Iran
Mosayeb Kamari - National Iranian South Oil Company

The importance of PVT properties, such as bubble point pressure, solution gas-oil ratio and oil formation volume factor, makes their accurate determination necessary for reservoir performance calculations.Ideally, crude oil properties are determined experimentally in the laboratory on actual fluid samples taken from thefield under study. However, when only invalid samples are available or in the absence of experimentally measured crude oil properties, especially during the prospecting phase, one can resort to empirically derived PVT correlations. Several correlations have been proposed for determining PVT properties. Limitations concerning the validity of thesecorrelations for various types of hydrocarbon systems, range of applicability, accuracy, corrections for nonhydrocarbonscontents, etc., have been controversial. Due to regional changes in crude oil compositions, a universal correlation which can be applied to different types ofcrude oils would be difficult to obtain. Therefore, correlations for a local region, where crude properties are expected tobe uniform, would be a necessary alternative. This paper derives and tests a new correlation to predict bubble poit pressure for Middle East crudes by usingavailabe PVT data from Middle East reservoirs and compares the predicted bubble point pressures from the newcorrelation and the commonly used bubble point empirical correlations by applying them to 403 experimentally obtained data sets of different crude oil and gas mixtures from Middle East region. The correlation developed by thisstudy revealed more accurate results than the literature correlations and should work better for Middle East crudes.Also this empirical correlation should be valid for all types of oil and gas mixtures with properties falling within the range of the data used in this study.

PVT, bubble point pressure, Middle East, correlation