عنوان مقاله [English]
In this paper, two models, namely the Flory-Huggins (polymer) solutions theory and the model developed by Rassamdana and co-workers, which served as our basic model, were employed for estimating asphaltene precipitation. In the analyses, the asphaltene solubility parameter was initially considered as a function of pressure and was subsequently adjusted by varying the pressure with an aim of logical adjustment of the results with the asphaltene precipitation experimental data. The values established for the asphaltene solubility parameter in the first approach were somewhat underestimated compared to the reported values in the literature; however, the second approach gave more acceptable results. Finally, an empirical expression was proposed for asphaltene precipitation solubility estimation for the two oil samples with enhanced accuracy at different pressures.
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