(66c) Application of Aggregation Thermodynamics and Molecular Characterization to Study Asphaltene Precipitation of Bituminous Crude Oils

Adding paraffinic feedstock to bituminous crude oil significantly increases the risk of asphaltene precipitation. Both the onset point and yield of asphaltene precipitation are determined by the content and composition of the crude mixture. Comprehensive thermodynamic modeling explains and enables the prediction of such precipitation behavior. Recently, an aggregation thermodynamic framework [1] developed from Yen-Mullins hierarchy model for asphaltene [2] has been shown to successfully predict asphaltene precipitation from a wide range of solvent mixtures, which is applied in this study. Additionally, a molecule-based characterization technique [3] is employed to identify the molecular compositions of the petroleum fluids. Finally, the solvent power of the crude oil and its blends is calculated using a refined NRTL-SAC activity coefficient model. To demonstrate this methodology, we predict the asphaltene precipitation behavior of three heavy oils: Cold Lake, Athabasca, and Peace River.

Reference

[1] M. Wang, Y. Hao, M. R. Islam, and C.-C. Chen, "Aggregation thermodynamics for asphaltene precipitation," AIChE Journal, vol. 62, pp. 1254-1264, 2016.

[2] O. C. Mullins, "The Modified Yen Model†," Energy & Fuels, vol. 24, pp. 2179-2207, 2010.

[3] C.-C. Chen and H. Que, "Method of Characterizing Chemical Composition of Crude Oil For Petroleum Processing," US Patent Application Number: 2013/0185044, July 18, 2013.