During oil production, solution gas is liberated and forms a free-gas phase due to decline in reservoir pressure. The nature of the liberated gas phase is crucial to the reservoir drive mechanism.
If liberated, gas bubbles easily coalescence to form a mobile gas phase. This can support the reservoir energy by an effective gas-oil gravity drainage mechanism.
Conversely, the liberated gas may persist as disconnected gas bubbles. Then the gas bubbles can block individual pore/throats and thereby lower the effective permeability of the reservoir. The goal of the project is to determine the form and the contribution of the liberated gas to the oil production.
The task for the Ph.D. student will be to perform experimental studies of the gas liberation in a porous medium of a low permeability reservoir under decreasing pressure. Mobility of the formed gas bubbles and their effect on the effective oil permeability will be determined. The experiments will be accompanied by micro-modeling of the bubble production, mobility and coalescence, under relevant thermodynamic conditions.
The project is carried out in close collaboration with GEUS, where a postdoctoral researcher will work on large-scale reservoir modeling, accounting for the results of the PhD student.