Viscosity Prediction for Solvent-Diluted Live Bitumen and Heavy Oil at Temperatures Up to 175-deg-C

Abstract

Accurate predictions of heavy-oil and bitumen viscosity as a function of temperature, pressure, and composition are required for the design of thermal and solvent-based recovery methods. In this case study, the applicability of the recently developed Expanded Fluid (EF) viscosity model is tested on measured viscosities of diluted dead and live heavy oil and bitumen at temperatures from 20 to 175 C and pressures up to 10 MPa. Density and viscosity data were collected for a condensate solvent, dead (gas-free) bitumen, and dead heavy oil from western Canada, and for the corresponding live oils and diluted mixtures of the dead and live oils with condensate solvent. Solubility, density, and viscosity data for heavy oil saturated with carbon dioxide (CO 2 ) were obtained from the literature.The model was fitted to the data of the dead oils and the condensate with average relative deviations less than 11%. The viscosity of the live bitumen and heavy oil was then predicted to within 21 and 31% of the measured value on the basis of measured and calculated live-oil densities, respectively. Diluting the live and dead bitumen with 3 to 30 wt% condensate or carbon dioxide reduced the viscosity by one to three orders of magnitude, and the viscosities were predicted with an average relative deviation less than 16 and 24% on the basis of measured and calculated mixture densities, respectively.

Effect of Composition, Temperature, and Pressure on the Viscosities and Densities of Three Diesel Fuels

“…There are also several methods for modeling the viscosity of complex mixtures, including expanded fluid theory [31][32][33][34] , friction theory [35][36][37][38][39] , free volume theory (FVT) 40,41 , hard sphere models [42][43][44] , residual entropy scaling 45,46 , Eyring's absolute rate theory 47,48 , and GC methods [49][50][51][52] .…”

“…There are also several methods for modeling the viscosity of complex mixtures, including expanded fluid theory, − friction theory, − free volume theory (FVT), , hard-sphere models, − residual entropy scaling, , Eyring’s absolute rate theory, , and GC methods. − However, only a few modeling approaches allow for diesel viscosity predictions based on composition. Aquing et al modeled the viscosity of two diesel fuels using the GC methods of van Velzen et al and Sastri and Rao .…”

Thermo‐physical properties of n‐pentane/bitumen and n‐hexane/bitumen mixture systems

“…The density of n-pentane and n-hexane at each temperature and pressure was obtained from the NIST databank and the following equations were used to correlate the density of bitumen at the desired temperatures and pressures. [26] r In Equations (2a-c), r B is the density of bitumen in kg/m 3 , P is the pressure in MPa, and T is the temperature in 8C.…”

Entropy-scaling based pseudo-component viscosity and thermal conductivity models for hydrocarbon mixtures and fuels containing iso-alkanes and two-ring saturates

“…Various viscosity [1,11,12] and thermal conductivity [2,13,14] models have been proposed for fuels in the literature. These models range from empirical [15][16][17][18][19][20][21][22] to mixture [23] and pseudo-component models [1,2,13,14,[24][25][26][27][28][29][30][31][32][33][34][35], such as expanded fluid theory (EFT) [13,14,[25][26][27][28], friction theory (FT) [29][30][31][32][33], and free volume theory (FVT) [34,35].…”