Prediction of surface tension of athabasca bitumen

Density data are reported for the following mixtures at temperatures from 20 to 175 °C and pressures up to 40 MPa: ethane + n-decane, propane + n-decane, butane + n-decane, propane + toluene, and propane + cyclooctane, as well as bitumen diluted with ethane, propane, n-butane, n-pentane, n-heptane, and carbon dioxide. A straightforward excess volume based mixing rule is proposed to determine the density of liquid mixtures of hydrocarbons. Excess volumes are accounted for with a binary interaction parameter, and a correlation is proposed to estimate the interaction parameter when mixture data are unavailable. For dissolved gaseous solvents and liquid solvents near their critical point, the input to the mixing rule is their effective liquid density. Effective density correlations were developed for n-alkanes from methane to n-heptane and carbon dioxide. The method is only valid for mixtures in the liquid region with a reduced temperature below approximately 0.52 (or higher at higher pressure). The mixing rule with no excess volume predicted the density of over 60 binary mixtures of liquid hydrocarbons at 25 °C and hydrocarbon mixtures with dissolved gas components over a broad range of pressures and temperatures with an average deviation of less than 1% when the criterion for validity was met. The density of diluted bitumen mixtures was also predicted with the same accuracy. All of the data were fitted to within experimental error when using binary interaction parameters.

Section: Resultsmentioning

confidence: 99%

Density of Hydrocarbon Mixtures and Bitumen Diluted with Solvents and Dissolved Gases

Saryazdi

Motahhari

Schoeggl³

et al. 2013

“…Experimental data is essential for phase behavior and EOS modeling. Mehrotra and Svrcek − and Svrcek and Mehrotra , studied the effect of temperature and pressure on the gas solubility of Athabasca bitumen for carbon dioxide (CO 2 ), methane (CH 4 ), nitrogen (N 2 ), and a synthetic combustion gas mixture. They conducted almost the same study for Cold Lake, Wabasca, and Peace River bitumens.…”

Section: Theorymentioning

confidence: 99%

“…Similar data have been reported by Robinson et al on Athabasca bitumen saturated with carbon dioxide or ethane at higher temperatures and by Robinson and Sim on Cold Lake bitumen saturated with carbon dioxide. The experimental data of Mehrotra and Svrcek − and Svrcek and Mehrotra , are the most comprehensive sets of data. This study focused on Mehrotra−Svrcek and Svrcek−Mehrotra experimental data for tuning the EOS parameters.…”

Section: Theorymentioning

confidence: 99%

“…The molecular weight, specific gravity, and/or boiling point of each pseudocomponent are applied to available correlations to calculate the critical and physical properties of pseudocomponents. The pseudocomponents properties are applied to the Peng−Robinson EOS to calculate the solubility of different solvents in bitumen, and the modeling results are then compared to the experimental data of Mehrotra and Svrcek − and Svrcek and Mehrotra. , If an acceptable match is obtained, the pseudocomponent is accepted; otherwise, this procedure is repeated. Molecular weight, specific gravity, and/or the boiling point of the pseudocomponents are the tuning parameters for this step.…”

Section: Theorymentioning

confidence: 99%

See 1 more Smart Citation

Bitumen Characterization and Pseudocomponents Determination for Equation of State Modeling

Kariznovi¹,

Nourozieh²,

Abedi³

2010

The phase behavior and thermodynamic properties of heavy oil and bitumen are of crucial importance for their in situ recovery, pipeline transportation, and upgrading; however, bitumen is a complex mixture of organic compounds whose chemical structures are not well understood. Therefore, bitumen is commonly characterized as a mixture of pseudocomponents derived from experimental data. This manuscript is intended to characterize and define the thermodynamic properties of Alberta bitumens. It has been undertaken three specific objectives: the first is the characterization of the bitumen as a mixture of pseudocomponents. The second objective is calculation of the gas solubility of gas-saturated bitumens by using an equation of state (EOS). The final objective is the selection of a set of pseudocomponents that would be applicable for different types of bitumen; in other words, the pursuit of a universal set of pseudocomponents for an EOS, independent of bitumen type. Varying numbers of pseudocomponents have been tested against the experimental data in the literature for bitumen from different fields (Athabasca, Wabasca, Peace River, and Cold Lake) with four different solvents (CH4, C2H6, CO2, and N2). The results show that the Lee−Kesler correlation (Lee, B. I.; Kesler, M. G. AIChE J. 1975, 21, 510−527) has produced considerably better results than the other correlations; it also appears that the Lee−Kesler correlation is appropriate for bitumen/solvent systems to determine the critical properties of the pseudocomponents.

“…It is inferred that bitumen recovery is associated with the distribution of bitumen fractions in the bitumen layer on the sand grains at given initial bitumen compositions and operational parameters. Such speculation is reasonable because bitumen liberation is influenced by its surface properties, especially interfacial tension, which are affected by the distribution of polar and nonpolar fractions of bitumen on the surface of oil sands. − …”

Section: Introductionmentioning

confidence: 99%

Distribution of Saturates, Aromatics, Resins, and Asphaltenes Fractions in the Bituminous Layer of Athabasca Oil Sands

et al. 2013

The composition and distribution of saturates, aromatics, resins, and asphaltenes (SARA) fractions in the bituminous layer on the surface of Athabasca oil sands were identified using elemental analysis (EA), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (SEM) with an energy-dispersive spectrometer (EDS), and Fourier transform infrared spectrometry (FTIR). The contents of elements sulfur (S) and nitrogen (N) and the ratios of carbon/ sulfur (C/S) and carbon/nitrogen (C/N) were characterized as potential indicators for evaluating the distribution of SARA fractions in the bituminous layer. Results indicated that saturates and aromatics tend to deposit at the outer bituminous layer, while asphaltenes and resins were inclined to distribute at the inner layer. Results also suggested that the distribution of SARA fractions was thermodynamically dependent and susceptible to thermal treatment. On the basis of the experimental results, a conceptual distribution model was proposed, which is supposed to serve as a basis for future studies on the liberation of bitumen from oil sands and the operation conditions for oil sands processing.