Heavy Oil Recovery Technology Package #1: Quantification of Phase Behaviour of Alkane Solvent(s)-CO2-Water-Heavy Oil Systems under equilibrium and Nonequilibrium Conditions

Experimental and theoretical techniques have been developed to accurately determine phase behaviour of alkane solvent(s)-CO2-water-heavy oil systems at high pressures and elevated temperatures. In addition to a modified alpha function respectively for heavy hydrocarbon compounds and water, theoretical models have been developed for accurately predicting binary interaction parameter (BIP), equilibrium interfacial tension, saturation pressure and solubility, minimum miscibility pressure, and multiphase boundaries by treating heavy oil as one pseudocomponent and multiple pseudocomonents, respectively. It is for the first time that the enhanced swelling effect for the heavy oil due to the addition of C3H8 and C4H10 or their mixtures into CO2 stream has been explicitly and accurately quantified. Recently, our research has been expended into a new dimension to experimentally and theoretically quantifying the nonequilibrium phase behaviour and physical properties of the aforementioned systems at high pressures and elevated temperatures by treating heavy oil as multiple pseudo components.

Heavy Oil Recovery Technology Package #2: Coupling Heat and Mass Transfer of Alkane Solvents-CO2-Heavy Oil-Systems under Reservoir Conditions

Novel experimental and theoretical techniques together with mixing rules have been developed to determine not only apparent diffusion coefficient for a gas mixture in heavy oil, but also individual diffusion coefficient for each component of the gas mixture in heavy oil at high pressures and elevated temperatures, respectively. In addition to quantifying gas exsolution of foamy oil and changes in fluid properties, a novel methodology has been developed to theoretically and experimentally quantify preferential diffusion for each component of a gas mixture in heavy oil by treating heavy oil as one pseudo-component and multiple pseudo-components. By coupling heat and mass transfer, a generalized methodology has recently been developed to quantify the preferential diffusion of each component in a gas mixture-heavy oil system at high pressures and elevated temperatures by treating heavy oil as one pseudo-component and multiple pseudo-components, respectively. Alkane solvents diffuse faster than CO2 in heavy oil, while addition of alkane solvent(s) into CO2 stream not only enhances mass transfer, but also achieves an improved swelling effect of heavy oil.