کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
204266 460712 2012 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Prediction of fluid density at extreme conditions using the perturbed-chain SAFT equation correlated to high temperature, high pressure density data
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Prediction of fluid density at extreme conditions using the perturbed-chain SAFT equation correlated to high temperature, high pressure density data
چکیده انگلیسی

At pressures below ∼55 MPa, the perturbed chain – statistically associated fluid theory (PC-SAFT) gives reliable density predictions within ±2% for n-alkanes and other hydrocarbons. However, PC-SAFT tends to over-predict density values by as much as 5% at higher pressures, particularly for normal and branched alkanes. For many compounds, literature values for the three pure-component PC-SAFT parameters m, σ, and ɛ/kB are typically obtained by fitting the equation to sub-critical PρT data or occasionally both sub-critical and supercritical density data. A new set of pure-component PC-SAFT parameters for density prediction at extreme conditions is reported here by fitting the PC-SAFT equation to single-component density data collected at temperatures from ambient to 533 K and pressures from ∼6.9 to 276 MPa, rather than sub-critical density data since these high temperature, high pressure (HTHP) conditions are similar to conditions typically associated with petroleum recovery from ultra-deep formations. Density predictions made using the new, HTHP PC-SAFT pure-component parameters at HTHP conditions are clearly superior to those obtained using the original PC-SAFT parameters. Although a correction term can be applied to the ɛ/kB parameter to make HTHP PC-SAFT pure-component density predictions at pressures below 6.9 MPa only slightly inferior to predictions with the original PC-SAFT parameters, vapor–liquid equilibrium predictions with the original PC-SAFT parameters are clearly superior to predictions made with the HTHP parameters. Correlations are developed to accurately predict the HTHP PC-SAFT parameters for normal and branched alkanes for which there are either incomplete or nonexistent experimental density data sets.


► Original PC-SAFT equation overpredicts hydrocarbon densities by up to 5% at 276 MPa.
► The equation was fit to experimental density data at pressures to 276 MPa.
► New PC-SAFT parameters presented for hydrocarbons up to carbon number 40.
► Resulting density predictions differ by <±1% from exp. values between 6.9 and 276 MPa.
► Applications in engineering of ultra-deep petroleum reservoirs.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Fluid Phase Equilibria - Volume 319, 14 April 2012, Pages 55–66
نویسندگان
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