This project supports a cooperative research project by Professor Anthony Kovscek, Department of Petroleum Engineering at Stanford University, Stanford, California and Professors Serhat Akin and Suat Bagci of the Middle East Technical University, Ankara, Turkey. They plan to investigate mechanisms of governing oil production, and their mathematical description, by a recently introduced enhanced oil recovery (EOR) technique called vapor extraction (VAPEX). It is aimed at heavy oils (density ranges from 940 to 1000 kg/m3) which are far more viscous (greater than 100 cP) than conventional crude oils. This large viscosity frustrates production. The idea is to inject a suitable solvent, such as propane, into a heavy-oil reservoir to form a vapor filled chamber and to dissolve in the crude oil causing a reduction in its viscosity. The resulting solution drains by gravity to a well placed low in the formation. It is planned to study vapor chamber formation and gravity drainage in the laboratory using X-ray computed tomography (CT, i.e. CaT scan) to visualize fluid phases inside porous media, and to examine process mechanisms at the pore scale using transparent silicon micromodels. With this knowledge a mathematical/numerical model of the process will be developed.
Scope: The collaborating scientists have complementary experience and expertise needed to conduct the project. Dr. Kovscek's laboratory at Stanford has high-pressure silicon micromodels, which may give insights into the pore-level physics of the VAPEX process. Dr. Serhat Akin has in the past worked on several CT-scanning experimental projects in order to understand multi-phase fluid flow in porous media and measure relative permeabilities. The visits by the Turkish scientists to Stanford will help with the experimental results, contribute towards the modeling efforts, and build onto our knowledge of imaging multi-phase flow using CT scanners and silicon micromodels. This project fits the mission of the Division of International Programs (INT) for support of mutually beneficial research. This project is supported by the Division of International Programs, the Division of Earth Sciences, and the Division of Civil and Mechanical Systems.