Malaysian crude bubble point pressure correlation revisit using multi linear regression.

Abstract

Hydrocarbon PVT data are one of the crucial inputs in reservoir engineering calculations. A laboratory study on reservoir fluids can be used to get these data, or they can be inferred from empirical correlations. Even though regulated reservoir conditions can improve the accuracy of laboratory results, the reliability of the hydrocarbon PVT is crucial. Empirically calculated PVT correlations can be used to estimate the physical reservoir fluid properties. It is useful in situations where experimental data cannot be collected or when it is necessary to cross-check the laboratory results. This paper outlines the development of the best correlation that has a superior result than any correlations in the market. The study employed a total of 93 PVT data collected from several offshore oil sites in Malaysia. The oil gravity range in the PVT data is 26.6 API to 53.2 API, and the bubble point pressures range from 790 psia to 3851 psia. The crudes have a low nitrogen concentration and are essentially hydrogen sulfide-free (maximum of 1.15 per cent). For Malaysian crudes, a new bubble point pressure black oil correlation was developed using multi-linear regression analysis. By doing a statistical and graphical error analysis, the precision of the new correlations was ascertained. The new bubble point pressure correlation has the lowest AAPRE (8.539%), lowest standard deviation (7.163%) and lowest maximum AAPRE (28.944%) as compared to the other correlations from the literature. The findings demonstrate that compared to previously known correlations found in the literature, the novel correlations provide more accuracy in determining reservoir fluid characteristics of Malaysian crudes. The new correlation result in low absolute average per cent relative error and standard deviation values as compared to the correlation from the literature.