scholarly journals Theoretical Derivation of Diagram of Vapor-Liquid Equilibrium in Binary Solution at Constant Temperature-Correlation of Partial Pressure of each Components in the Vapor Phase with Composition in the Liquid Phase.

1956 ◽  
Vol 59 (12) ◽  
pp. 1375-1378 ◽  
Author(s):  
Atsushi Ikari
2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Daming Gao ◽  
Hui Zhang ◽  
Peter Lücking ◽  
Hong Sun ◽  
Jingyu Si ◽  
...  

Vapor-liquid equilibrium (VLE) data for the strongly associated ternary system methanol + water + ethanoic acid and the three constituent binary systems have been determined by the total pressure-temperature-liquid-phase composition-molar excess enthalpy of mixing of the liquid phase (p, T, x, HmE) for the binary systems using a novel pump ebulliometer at 101.325 kPa. The vapor-phase compositions of these binary systems had been calculated from Tpx and HmE based on the Q function of molar excess Gibbs energy through an indirect method. Moreover, the experimental T, x data are used to estimate nonrandom two-liquid (NRTL), Wilson, Margules, and van Laar model parameters, and these parameters in turn are used to calculate vapor-phase compositions. The activity coefficients of the solution were correlated with NRTL, Wilson, Margules, and van Laar models through fitting by least-squares method. The VLE data of the ternary system were well predicted from these binary interaction parameters of NRTL, Wilson, Margules, and van Laar model parameters without any additional adjustment to build the thermodynamic model of VLE for the ternary system and obtain the vapor-phase compositions and the calculated bubble points.


1983 ◽  
Vol 23 (04) ◽  
pp. 587-594 ◽  
Author(s):  
James P. Frimodig ◽  
Norman A. Reese ◽  
Craig A. Williams

Abstract Engineering methods are being developed to evaluate reservoir fluid systems for Suitability to CO2 flooding. This paper presents our evaluation procedure as applied to laboratory data for a high-pour-point [95 degrees F (35 degrees C)] oil from the Red Wash field in Utah. The data were obtained from phase behavior and slim tube experiments. The results of this work indicate that high pressures are required for a miscible displacement of the highly paraffinic. high-pour-point Red Wash oil. The minimum miscibility pressure (MMP) was found to be 4,650 psia (32 060 kPa), increasing only 5% to 4,900 psia (33 784 kPa) when the injected CO2 contains a 10 mol% nitrogen contaminant. These pressures are not currently economically obtainable in the Red Wash field. lntroduction The Red Wash field is located in Utah in the northeastern Uinta basin. With a comparatively low ultimate recovery predicted from primary depletion and waterflooding operations, the field is considered an attractive condidate for tertiary recovery methods. The work reported in this paper presents laboratory experiments and calculation techniques used in evaluating reservoir fluids for CO2 flooding. The laboratory work includes constant composition experiments, vapor/liquid equilibrium experiments, liquid-phase viscosity experiments, and slimtube multiple-contact miscibility experiments. Calculation techniques utilized a two-constant equation of state (EOS) to predict phase behavior and fluid properties. One CO2 source available in the area contains approximately 10 mol% nitrogen. To evaluate the effect of nitrogen contamination, experiments were performed with two different gases, one with and one without the nitrogen contaminant. Red Wash Oil/CO, Gas Physical Property Measurements Physical property data for the Red Wash oil/CO2 gas system were obtained from constant composition expansion (CCE), vapor/liquid equilibration (VLE), and liquid-phase viscosity experiments. CCE experiments were conducted to determine the pressure/composition behavior (bubble-point/dew-point envelope) of Red Wash oil and injection gases. VLE experiments measured vapor/liquid equilibrium constants (K values). Liquid-phase viscosities determine to what extent injection gases dissolved in the liquid phase affect the flow behavior of the reservoir oil. All experiments used Red Wash reservoir oil and two different injection gases. The first CO2 gas (Gas 1 ) was approximately 5 mol% methane and 95 mol % CO 2. The second CO2 gas (Gas 2) contained about 10 mol% nitrogen, 5 mol% methane, and 85 mol %, CO2. The exact compositions of Gases 1 and 2 and Red Wash reservoir oil are shown in Table 1. CCE Experiments A high-pressure visual PVT cell was used in the CCE experiments. All experiments were conducted at the reported reservoir temperature of 130 degrees F (54.4 degrees C). During each CCE the visual cell was loaded with measured volumes of Red Wash oil and injection gas. SPEJ P. 587^


2019 ◽  
Vol 25 (1) ◽  
pp. 67-76
Author(s):  
Ljiljana Zivanic ◽  
Marko Stamenic ◽  
Branislav Todic ◽  
Dragomir Bukur ◽  
Nikola Nikacevic

Predictions of vapor liquid equilibrium for Fischer-Tropsch mixtures were compared using the classical Soave-Redlich-Kwong (SRK) and cubic-plus-association (CPA) equations of state. The performance of the two equations of state was evaluated based on comparison with results from eight sets of experimental runs in which different process conditions (pressure, reactants feed ratio, space velocity) were used. Flash calculations were used to determine the phase split at defined process conditions, whereas the phase equilibrium was defined utilizing the concept of equal fugacities in the vapor and the liquid phase for all components. A total of 75 components were considered in the reaction mixture: CO, H2, H2O, CO2, C1-C57 paraffins and C2-C15 olefins. All calculations were performed in MATLAB. The results showed that both equations of state had similar performance regarding the hydrocarbons, whereas CPA gave better results with inorganic components and SRK with prediction of the composition of the liquid phase. Computational time for CPA was substantially (100 times with the CPU used) higher than that for SRK. Overall, the use of CPA did not improve VLE prediction for FTS systems significantly enough to be recommended for use in FTS reactor models.


2012 ◽  
Vol 550-553 ◽  
pp. 2704-2711
Author(s):  
Hong Bo Tang ◽  
Min Qing Zhang

Many researchers have shown a great deal of interest in the effects that magnetic fields have when applied in chemical reactions, crystallization, magnetic separation of materials, magnetic levitation, materials processing, and wastewater treatment. However, surprisingly little research has been done on the effects of magnetic fields on the vapor-liquid equilibrium and the thermodynamic model for vapor-liquid phase equilibrium. The influence of magnetic fields on vapor-liquid equilibrium of binary heterogeneous azeotrope was investigated with ethanol-water in this paper. It was found that the vapor-liquid equilibrium of an ethanol-water system is influenced by the external magnetic field, but that the azeotropic point of the ethanol-water system is not changed by the magnetic field when the magnetic intensity reaches 0.8 T. Rather, the exerted magnetic field reduces the equilibrium temperature and shortens the distance between T-x curve and T-y curve in T-x-y diagram of the vapor-liquid equilibrium of the ethanol-water system. A thermodynamic model for vapor-liquid phase equilibrium in the exerted magnetic field was derived theoretically, based on the fundamental thermodynamic theory. The results show that the logarithm value of the ratio of the composition of the certain component in a magnetic field to that without the magnetic field is proportional to the magnetic susceptibility of the solution, and to the square of magnetic field intensity. This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text.


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