Derivation of PVT Correlations for the Gulf of Suez Crude Oils

Abstract

Proper evaluation of physical properties of hydrocarbon mixtures is a prerequisite for the design of various stages of oil field operations. In many cases these properties are required at a time when the only information available consists of oil and gas gravities and reservoir pressure and temperature. The purpose of this study is to utilize a sufficient base of laboratory-measured PVT data to derive specific empirical correlations for the prediction of the saturation pressure Pb, gas in solution Rs and formation volume factor β0 of Gulf of Suez crude oil systems, °API of which ranges from 25 up to 40. Our tool in this work is some of regression analyses techniques. The correlations are based on 90 experimentally measured data which represent about 30 independent reservoirs. These data are expressed in terms of the usually measured field parameters-flash separation gas-oil ratio, tank oil gravity, surface gas gravity (at separator conditions) and reservoir temperature. Derived correlations are valid within the ranges used for the above mentioned variables (GOR, T, γg). The gases are relatively free from non-hydrocarbons. Statistical accuracy tests show that the application of derived correlations for Egyptian reservoirs gives more accuracy than the known correlations (Standing and Glaso). The use of the derived relationships requires no graphs nor charts, and their applicability is convenient to use with the computer or calculator. © 1993, The Japan Petroleum Institute. All rights reserved.