Numerical investigation on vapour-liquid equilibrium and gas solubility in hydrocarbons for binary and ternary systems
DOI:
https://doi.org/10.24425/ather.2025.154179Abstract
Vapour-liquid equilibrium calculation is crucial in oil industry and multi-phase systems such as droplet evaporation. This paper presents a comprehensive numerical analysis of phase equilibrium in multi-component systems at various pressures and temperatures, accounting for high-pressure phenomena including thermodynamic non-ideality and inert gas effects. The phase equilibrium is determined by solving the fugacity equation iteratively to find the equilibrium mole fractions in both liquid and vapour phases. The Peng-Robinson equation of state is used to handle non-idealities and calculate fugacity coefficients. This study details the procedure for computing vapour-liquid equilibrium and evaluates N2, O2, and CO2 solubility in liquid alkanes such as heptane, dodecane, and hexadecane. Model performance is validated against experimental data for binary and ternary systems, showing good agreement. Results indicate that density and molecular attractive forces impact gas dissolution. Increased pressure and gas density enhance solubility in the liquid phase, while temperature effects vary between subcritical and supercritical regions. The study also highlights differences in gas solubility between heavy and light fluids.References
[1] Sirignano, W.A. (2010). Fluid dynamics and transport of droplets and sprays (2nd ed.). Cambridge University Press. https://doi.org/10.1017/CBO9780511806728
[2] Lynch, M. (2001). Phase behavior. Current Opinion in Colloid and Interface Science, 6(4), 402–404. Henry L. Doherty Memorial Fund of AIME, Society of Petroleum Engineers. https://doi.org/10.1016/S1359-0294(01)00109-1
[3] Riazi, M.R. (2005). Characterization and properties of petroleum fractions. ASTM International.
[4] Mühlbauer, A.L., & Raal, J.D. (1995). Computation and thermodynamic interpretation of high‑pressure vapour–liquid equilibrium – a review. The Chemical Engineering Journal and The Biochemical Engineering Journal, 60(1–3), 1–29. https://doi.org/10.1016/0923-0467(95)02980-X
[5] Rojas, M., Figueira, F., & Zeppieri, S. (2014). Prediction of hydrogen solubility in PYGAS with equations of state. Journal of Computational Methods in Sciences and Engineering, 14(1–3), 137–153. https://doi.org/10.3233/JCM-140492
[6] Ghosh, P. (1999). Prediction of vapor–liquid equilibria using Peng–Robinson and Soave–Redlich–Kwong equations of state. Chemical Engineering and Technology, 22(5), 379–399. https://doi.org/10.1002/(SICI)1521-4125(199905)22:5<379::AID-CEAT379>3.0.CO;2-Q
[7] Lyu, Z., Ma, H., Zhang, H., & Ying, W. (2018). Solubility of carbon dioxide in methanol from 213.15 K to 273.15 K: Measurement and modeling. Fluid Phase Equilibria, 471, 40–54. https://doi.org/10.1016/j.fluid.2018.04.014
[8] Chaparro, G., Cartes, M., & Mejía, A. (2020). Vapor–liquid equilibrium at 94 kPa and surface tension at 298.15 K for hexane + ethanol + cyclopentyl methyl ether mixture. Fuel, 279, 118415. https://doi.org/10.1016/j.fuel.2020.118415
[9] Laursen, T., & Andersen, S.I. (2002). High‑pressure vapor–liquid equilibrium for nitrogen + methanol. Journal of Chemical and Engineering Data, 47(5), 1173–1174. https://doi.org/10.1021/je020006z
[10] Höhler, F., Deschermeier, R., Rehfeldt, S., & Klein, H. (2018). Gas solubilities of carbon dioxide in methanol, acetone, mixtures of methanol and water, and mixtures of methanol and acetone. Fluid Phase Equilibria, 459, 186–195. https://doi.org/10.1016/j.fluid.2017.12.004
[11] Yang, W., Xia, J., Wang, X.Y., Wan, K.D., Megaritis, A., & Zhao, H. (2021). Predicting evaporation dynamics of a multicomponent gasoline/ethanol droplet and spray using non‑ideal vapour–liquid equilibrium models. International Journal of Heat and Mass Transfer, 168, 120876. https://doi.org/10.1016/j.ijheatmasstransfer.2020.120876
[12] Ray, S., Sree Harsha, V.V., & Raghavan, V. (2019). Prediction of vapor–liquid equilibrium of ternary system at high pressures. Archives of Thermodynamics, 40(2), 137–149. https://doi.org/10.24425/ather.2019.129545
[13] Koretsky, M.D. (2012). Engineering and chemical thermodynamics (2nd ed.). John Wiley & Sons.
[14] Poling, B.E., Prausnitz, J.M., & O’Connell, J.P. (2001). The properties of gases and liquids. McGraw‑Hill Education.
[15] Jorda, J.A., & Sirignano, W.A. (2017). Analytical/computational approach to liquid spray heating and vaporization at supercritical pressures. ILASS‑Europe, 28th European Conference on Liquid Atomization and Spray Systems, Valencia, Spain, pp. 686–693. https://doi.org/10.4995/ilass2017.2017.4615
[16] Lin, H.M., Kim, H., & Chao, K.C. (1981). Gas–liquid equilibria in nitrogen + n‑hexadecane mixtures at elevated temperatures and pressures. Fluid Phase Equilibria, 7(2), 181–185. https://doi.org/10.1016/0378-3812(81)85020-0
[17] Nemati Lay, E., Taghikhani, V., & Ghotbi, C. (2006). Measurement and correlation of CO₂ solubility in the systems of CO₂ + toluene, CO₂ + benzene, and CO₂ + n‑hexane at near‑critical and supercritical conditions. Journal of Chemical and Engineering Data, 51(6), 2197–2200. https://doi.org/10.1021/je0602972
[18] Lin, H.-M., Sebastian, H.M., & Chao, K.-C. (1980). Gas–liquid equilibrium in hydrogen + n‑hexadecane and methane + n‑hexadecane at elevated temperatures and pressures. Journal of Chemical and Engineering Data, 25(3), 252–254. https://doi.org/10.1021/je60086a012
[19] Søreide, I., & Whitson, C.H. (1992). Peng–Robinson predictions for hydrocarbons, CO₂, N₂, and H₂S with pure water and NaCl brine. Fluid Phase Equilibria, 77, 217–240. https://doi.org/10.1016/0378-3812(92)85105-H
[20] Uribe‑Vargas, V., & Trejo, A. (2004). Vapor–liquid equilibrium of nitrogen in an equimolar hexane + decane mixture at temperatures of 258, 273, and 298 K and pressures to 20 MPa. Fluid Phase Equilibria, 220(2), 137–145. https://doi.org/10.1016/j.fluid.2004.03.009
[21] Dhima, A., de Hemptinne, J.-C., & Jose, J. (1999). Solubility of hydrocarbons and CO₂ mixtures in water under high pressure. Industrial & Engineering Chemistry Research, 38(8), 3144–3161. https://doi.org/10.1021/ie980768g
[22] Camacho‑Camacho, L.E., Galicia‑Luna, L.A., & Elizalde‑Solis, O. (2011). Vapor–liquid equilibria of binary and ternary systems containing carbon dioxide, alkane, and benzothiophene. Journal of Chemical & Engineering Data, 56(11), 4109–4115. https://doi.org/10.1021/je200586g
