An improved Wilson equation for phase equilibrium K values estimation
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Wayne D. Monnery
Abstract
Phase equilibrium K values are either estimated with empirical correlations or rigorously calculated based on fugacity values determined from an equation of state. There have been several empirical analytical equations such as Raoult’s Law, the Hoffman Equations (Hoffman A, Crump J, Hocott C. Equilibrium constants for a gas condensate system. J Petrol Technol 1953;5:1–10) and their modifications and the well-known Wilson Equation (Wilson G. A modified Redlich–Kwong equation of state applicable to general physical data calculations. In: AIChE National Meeting Paper15C, May 4–7, Cleveland, OH; 1969). along with several modifications. This work presents a new modification of the Wilson Equation for estimating phase equilibrium K values, predominantly for light hydrocarbon mixtures. The modification is based on correlating a subset of a database of K values, established from convergence pressure data. Results show the method to accurately correlate and predict the K value data, within 10% on average. Moreover, the predicted K factors provide remarkable results for such a simple model when used in a variety of phase equilibrium calculations. The results also show that the new model compares favorably with existing empirical analytical methods. Such a model would provide excellent initial estimates for rigorous thermodynamic calculations.
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Author contribution: The author has accepted responsibility for the entire content of this submitted manuscript and approved submission.
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Research funding: None declared.
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Conflict of interest statement: The author declares no conflicts of interest regarding this article.
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Articles in the same Issue
- Frontmatter
- Editorial
- CPPM special issue in honour of Emeritus Professor W.Y. “Bill” Svrcek
- Research Articles
- Asphaltene precipitation from heavy oil mixed with binary and ternary solvent blends
- Kinetic modeling of biosurfactant production by Bacillus subtilis N3-1P using brewery waste
- A user workflow for combining process simulation and pinch analysis considering ecological factors
- An improved Wilson equation for phase equilibrium K values estimation
- Process model correlating Athabasca bitumen thermally cracked at edge of coking induction zone
- Flexible digital twins from commercial off-the-shelf software solutions: a driver for energy efficiency and decarbonisation in process industries?
