A Tangent-Line Approach for Effective Density Used in Ideal Mixing Rule: Part I—Prediction of Density for Heavy-Oil/Bitumen Associated Systems

SPE Journal ◽  
2019 ◽  
Vol 25 (03) ◽  
pp. 1140-1154 ◽  
Author(s):  
Zehua Chen ◽  
Daoyong Yang
Keyword(s):  
Heavy Oil ◽  
Tangent Line ◽  
Effective Density ◽  
Gas Mixture ◽  
Mixing Rule ◽  
Volatile Oils ◽  
Ideal Mixing ◽  
Rich Liquid ◽  
Oil Gas ◽  
The Ideal

Summary Accurate prediction of density of an oil/gas mixture by using the ideal mixing (IM) rule is a great challenge, and its progress is still far from satisfactory. The method proposed by Standing and Katz (1942) for determining methane and ethane apparent densities is limited to only black oils and volatile oils. The methods recently proposed by Saryazdi (2012) and Saryazdi et al. (2013) to determine effective densities of methane through n-heptane (C1 through n-C7) and CO2 have shown some success, respectively, though limitations remain and the extent of their applications is still constrained. In this study, we developed a tangent-line approach for the effective density of C1 through n-C8, CO2, N2, toluene, cyclohexane, and dimethyl ether (DME). This method is more general and flexible than the extrapolation method proposed by Saryazdi (2012). A comprehensive database is established to first develop new correlations with one set of data and then compare them with the other. We successfully extended using the IM rule with effective density (IM-E) to condensate/bitumen systems, solvent/bitumen fraction systems, and solvent/bitumen systems with substantial extraction [i.e., emergence of a solvent-rich liquid phase (denoted as the L1 phase)] by properly treating the densities of condensate, bitumen fractions, extracts, and residues. This study focuses on heavy-oil/bitumen-associated systems, and the observed patterns and trends for different systems will be presented and explained in Part II of this study (Chen and Yang 2020).

A Tangent-Line Approach for Effective Density Used in the Ideal Mixing Rule: Part II—Evaluation of Mixing Characteristics of Oil/Gas Systems and Application Criteria

SPE Journal ◽  
2020 ◽  
Vol 25 (06) ◽  
pp. 3160-3185
Author(s):  
Zehua Chen ◽  
Daoyong (Tony) Yang
Keyword(s):  
Tangent Line ◽  
Solid Particles ◽  
Effective Density ◽  
Mixing Rule ◽  
Ideal Mixing ◽  
Mixing Characteristics ◽  
Oil Gas ◽  
Solvent Fraction ◽  
The Ideal ◽  
Real Density

Summary Although in Part I of this study (Chen and Yang 2020) we developed a tangent-line approach for effective density that is more general, robust, and flexible than the methods proposed by Saryazdi (2012) and Saryazdi et al. (2013), its application is only limited to heavy-oil/bitumen-associated mixtures [i.e., specifically, it has only been applied to bitumen-rich liquid phase (denoted as L2)]. As indicated in Part I, the density of nitrogen (N2)/hydrocarbon mixtures cannot be accurately predicted by using the ideal mixing rule (IM) with either real density or effective density. Not only do we need to explain and evaluate the observed deviations and patterns, but also the density prediction of solvent/Fraction 1 systems [i.e., Fraction 1 of the Athabasca bitumen, which has a molecular weight (MW) of 268.8 g/mol, as reported in Azinfar et al. (2018a, 2018b, 2018c)] needs to be improved for practical use. In this study, we evaluate the mixing characteristics of different molecules in a mixture using the tangent-line approach. By evaluating and comparing performances of the IM with effective density (IM-E) and the IM with real density (IM-R), the observed patterns and deviations together with those calculated from the Westman equation indicate that the oil/gas molecules somewhat behave like solid particles in mixing. Accordingly, we further modify the effective density used in the IM to bridge the gap between the IM-E and the IM-R. The database has been extended to light-oil/gas systems such as black oils, volatile oils, gas condensates, carbon dioxide (CO2) miscible fluids, sour gases, and wet/dry gases. The IM with modified effective density (IM-ME) has also been applied to solvent/Fraction 1 systems and the C2 or C3 or n-C4-extraction L1 phase (bitumen-related mixtures) with better accuracy. Also, we develop new criteria for the uses of the IM-E, IM-ME, and IM-R that can cover the density predictions for almost all types of oil/gas systems in the petroleum industry with high accuracy. The performances of the IM are thoroughly evaluated and compared with the volume-translated (VT) Peng-Robinson equation of state (EOS) (VT PR EOS), from which the deviations provide new insights for accurately quantifying the mixture density in a more robust and reliable manner.

A Power-Law Mixing Rule for Predicting Apparent Diffusion Coefficients of Binary Gas Mixtures in Heavy Oil

2017 ◽  
Vol 140 (5) ◽  
Author(s):  
Hyun Woong Jang ◽  
Daoyong Yang ◽  
Huazhou Li
Keyword(s):  
Diffusion Coefficient ◽  
Apparent Diffusion Coefficient ◽  
Heavy Oil ◽  
Diffusion Coefficients ◽  
Gas Mixtures ◽  
Gas Diffusion ◽  
Gas Mixture ◽  
Mixing Rule ◽  
Heavy Oils ◽  
Apparent Diffusion

A power-law mixing rule has been developed to determine apparent diffusion coefficient of a binary gas mixture on the basis of molecular diffusion coefficients for pure gases in heavy oil. Diffusion coefficient of a pure gas under different pressures and different temperatures is predicted on the basis of the Hayduk and Cheng's equation incorporating the principle of corresponding states for one-dimensional gas diffusion in heavy oil such as the diffusion in a pressure–volume–temperature (PVT) cell. Meanwhile, a specific surface area term is added to the generated equation for three-dimensional gas diffusion in heavy oil such as the diffusion in a pendant drop. In this study, the newly developed correlations are used to reproduce the measured diffusion coefficients for pure gases diffusing in three different heavy oils, i.e., two Lloydminster heavy oils and a Cactus Lake heavy oil. Then, such predicted pure gas diffusion coefficients are adjusted based on reduced pressure, reduced temperature, and equilibrium ratio to determine apparent diffusion coefficient for a gas mixture in heavy oil, where the equilibrium ratios for hydrocarbon gases and CO2 are determined by using the equilibrium ratio charts and Standing's equations, respectively. It has been found for various gas mixtures in two different Lloydminster heavy oils that the newly developed empirical mixing rule is able to reproduce the apparent diffusion coefficient for binary gas mixtures in heavy oil with a good accuracy. For the pure gas diffusion in heavy oil, the absolute average relative deviations (AARDs) for diffusion systems with two different Lloydminster heavy oils and a Cactus Lake heavy oil are calculated to be 2.54%, 14.79%, and 6.36%, respectively. Meanwhile, for the binary gas mixture diffusion in heavy oil, the AARDs for diffusion systems with two different Lloydminster heavy oils are found to be 3.56% and 6.86%, respectively.

scholarly journals Research on heavy oil gas lift assisted with light oil injected from the annulus

2018 ◽  
Vol 8 (4) ◽  
pp. 1465-1471 ◽  
Author(s):  
H. Q. Zhong ◽  
S. Zhu ◽  
W. G. Zeng ◽  
X. L. Wang ◽  
F. Zhang
Keyword(s):  
Heavy Oil ◽  
Light Oil ◽  
Oil Gas ◽  
Gas Lift

Nonlinear Double-Log Mixing Rule for Viscosity Calculation of Bitumen/Solvent Mixtures Applicable for Reservoir Simulation of Solvent-Based Recovery Processes

SPE Journal ◽  
2020 ◽  
Vol 25 (05) ◽  
pp. 2648-2662
Author(s):  
Hossein Nourozieh ◽  
Ehsan Ranjbar ◽  
Anjani Kumar ◽  
Kevin Forrester ◽  
Mohsen Sadeghi
Keyword(s):  
Reservoir Simulation ◽  
Heavy Oil ◽  
Viscosity Reduction ◽  
Viscosity Data ◽  
Solvent Mixtures ◽  
Mixing Rule ◽  
Arrhenius Model ◽  
Recovery Processes ◽  
Mixture Phase ◽  
Mixture Viscosity

Summary Various solvent-based recovery processes for bitumen and heavy-oil reservoirs have gained much interest in recent years. In these processes, viscosity reduction is attained not only because of thermal effects, but also by dilution of bitumen with a solvent. Accurate characterization of the oil/solvent-mixture viscosity is critical for accurate prediction of recovery and effectiveness of such processes. There are varieties of models designed to predict and correlate the mixture viscosities. Among them, the linear log mixing (Arrhenius) model is the most commonly used method in the oil industry. This model, originally proposed for light oils, often show poor performance (40 to 60% error) when applied to highly viscous fluids such as heavy oil and bitumen. The modified Arrhenius model, called the nonlinear log mixing model, gives slightly better predictions compared with the original Arrhenius model. However, the predictions still might not be acceptable because of large deviations from measured experimental data. Calculated mixture-phase viscosity has a significant effect on flow calculations in commercial reservoir simulators. Underestimation of mixture viscosities leads to overprediction of oil-production rates. Using such mixing models in reservoir simulation can lead to inaccuracy in mixture viscosities and hence large uncertainty in model results. In the present study, different correlations and mixing rules available in the literature are evaluated against the mixture-viscosity data for a variety of bitumen/solvent systems. A new form (nonlinear) of the double-log mixing rule is proposed, which shows a significant improvement over the existing models on predicting viscosities of bitumen/solvent mixtures, especially at high temperatures.

scholarly journals THE POSSIBLE DI-OMEGA DIBARYON IN QUARK CLUSTER MODEL

2014 ◽  
Vol 26 ◽  
pp. 1460120 ◽  
Author(s):  
L. R. DAI ◽  
J. LIU ◽  
L. YUAN
Keyword(s):  
Binding Energy ◽  
Quark Model ◽  
Cluster Model ◽  
Bound State ◽  
Nucleon Nucleon ◽  
Scattering Data ◽  
Nucleon Scattering ◽  
Scalar Mesons ◽  
Ideal Mixing ◽  
The Ideal

The mixing of scalar mesons is introduced into the baryon-baryon system in the chiral SU(3) quark model to further dynamically investigate the Di-omega state by using the same parameters as those in reasonably describing the experimental hyperon-nucleon and nucleon-nucleon scattering data. Two different mixings of scalar mesons, the ideal mixing and 19° mixing, are discussed, and compared with no mixing. The results show that it is still deeply bound state if 19° mixing is adopted, the same as those of no mixing. However, for ideal mixing, the binding energy is reduced quite a lot, yet it is still a bound state.

Effects of the surface roughness on the entrainment heights of oil–gas mixture impingement on the vertical wall

2021 ◽  
Vol 229 ◽  
pp. 116149
Author(s):  
Lingzi Wang ◽  
Jianmei Feng ◽  
Tiendat Dang ◽  
Xueyuan Peng
Keyword(s):  
Surface Roughness ◽  
Vertical Wall ◽  
Gas Mixture ◽  
Oil Gas
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