Measurements of the Density and Viscosity of Heavy Oil and Water-in-Oil Emulsions Over a Wide Temperature Range

Abstract

Density and dynamic viscosity of extra viscous heavy crude oil and water-in-oil (W/O) suspensions based on Ashalchinskaya (Tatarstan, Russian Federation) oil have been measured as a function of temperature and concentration of water at atmospheric pressure. The measurements were made at temperatures from (293 to 463) for density and from (293 to 367) K for viscosity with various concentrations of water (from 0 % to 30 % volume fraction). Measurements were made using modified hydrostatic weighing for density and falling body techniques for viscosity. The combined expanded uncertainty of the density, viscosity, pressure, and temperature measurements at 0.95 confidence level with a coverage factor of k = 2 is estimated to be $$U\left( \rho \right)$$ = 0.16 % and $$U\left( \eta \right)$$ = 1.0 %, $$U\left( P \right)$$ = 1.0 %, and $$U\left( T \right)$$ = 0.02 K, respectively. The reliability and accuracy of the new experimental method and correct operation of the modified experimental apparatus was confirmed with measurements using different methods (pycnometric, capillary flow, commercial standard instruments, Brookfield rotational viscometer). The effect of temperature and concentration of water on the measured values of density and viscosity of W/O suspensions were studied. Using crude dry oil, the effective viscosities of several synthetic W/O emulsions are measured at atmospheric pressure using a commercial standard instrument, Brookfield rotational viscometer and falling body technique for different shear rates, temperatures and volume fractions of the dispersed phase. The various correlation equations for describing viscosity as a function of temperature and dispersed phase volume fraction is developed. A number of factors such as water content, shear rate, shear stress, and temperature and their effects on the density and dynamic viscosity of dry crude oil and W/O emulsions were assessed.