Estimation of Missing Molecular Weight and Specific Gravity of Heptane Plus Fraction in PVT Laboratory Report

The molecular weight and specific gravity of heptane plus fractions (C7+) are essential in characterizing crude oils. The hydrocarbon analysis of reservoir fluid test usually reports molecular weight and specific gravity of C7+ in the PVT report. Sometimes these values are missing; therefore, estimating them is crucial. This study aims to develop new empirical correlations to estimate the missing molecular weight and specific gravity of the C7+. The experimentally measured hydrocarbon analysis of reservoir fluid tests from the Middle East crudes is the basis for developing the correlations. The input parameters for the correlations are available molecular weight, the specific gravity of C7+, and stock tank oil-specific gravity. The newly developed correlations outperform the existing correlations based on high correlation coefficients and low values of average absolute percent relative error and standard deviation.