Hydrocarbon/water and CO(sub 2) systems are frequently found in petroleum recovery processes, petroleum refining, and gasification of coals, lignites and tar sands. Techniques to estimate the phase volume and phase composition are indispensable to design and improve oil recovery processes such as steam, hot water, or CO(sub 2)/steam combinations of flooding techniques typically used for heavy oils. An interdisciplinary research program to quantify transport, PVT, and equilibrium properties of selected oil/CO(sub 2)/water mixtures at pressures up to 10,000 psia and at temperatures up to 500 F has been put in place. The objectives of this research include experimental determination and rigorous modeling and computation of phase equilibrium diagrams, and volumetric properties of hydrocarbon/CO(sub 2)/water mixtures at pressures and temperatures typical of steam injection processes for thermal recovery of heavy oils. Highlighting the importance of phase behavior, researchers insist on obtaining truly representative reservoir fluids samples for experimental analysis. A new method to compute multi-component phase equilibrium diagrams based on an improved version of the Peng-Robinson equation has been developed. This new version of the Peng-Robinson equation uses a new volume translation scheme and new mixing rules to improve the accuracy of the calculations. Calculations involving multicomponent mixtures of CO2/water and hydrocarbons have been completed. A scheme to lump multi-component materials such as, oils into a small set of 'pseudo-components' according to the technique outlined by Whitson has been implemented. This final report presents the results of our experimental and predicted phase behavior diagrams and calculations for mixtures of CO2/water and real oils at high pressures and temperatures.
PDF
download
878987797
028-85220240
