Method of calculation of molecular weights and densities of hydrocarbon fractions of reservoir fluids

Properties of hydrocarbon fractions for phase change simulation are uncertain and in most cases are taken from datasets (so-called libraries). Better way is to perform a TBP experiment toacquire molecular weights and densities and calculate the rest of the properties from these two. Dataset properties could turn up being not fit for a studied fluid, and experiments are expensive and time consuming. At the same time there is alot of experimental TBP results performed in Russian Federation with experimentally determined molecular weights and densities of fractions. Method of hydrocarbon fractions' molecular weightsand densities calculation is proposed, based on a statistical similarity of similar reservoir fluids.
Materials and methods
Materials - TBP results set with molecular weights and densities of narrow petroleum fractions determined experimentally; Methods - determination of fractionalcomposition of a petroleum fluid by ASTM D2887, GOST R 54291-2010 or similar (simulated distillation by gas chromatography), determination of molar weights by cryoscopic method, determination of hydrocarbon fluid density with densitometer.
Results
Presented method of molecular weights and densities calculation proved its effectiveness.
Сonclusions
Presented method could be used for producing primary data for phase behavior modeling of reservoir fluids when detailed experiments have not been performed.