A New Multi Parameter Heptane Plus Splitting Marching Scheme

Faisal Aladwani


A detailed and accurate composition for pseudo-components are essential in studies involves compositional analysis such as compositional simulator or surface flash calculations using equation of state. Such detailed composition requires experimental procedure in which the detailed composition is determined. Most of the time a detailed fluid composition study is not available and only the composition and molecular weight of the heptane plus component exist, hence methods are required to determine the detailed composition of the heavier hydrocarbon components. The new splitting model is developed using a database composed from 79 different samples collected from the literature in addition to 27 gas condensate and volatile oil samples obtained from a reservoir in the Middle East, in addition to two gas condensate samples measured in the KU-general facility lab. The developed splitting model has accurately characterized the samples composition using only molecular weight and mole fraction of the heptane plus pseudo-composition, which are commonly defined in conventional hydrocarbon fluid reports. Error analysis shows that the developed model outperformed existing models and accurately predicted the detailed composition of heavier hydrocarbon components.


heptane splitting, simplex optimization, marching algorithm

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