This study presents the results of nano-particle and surfactant-stabilized solvent-based emulsion bench test studies under laboratory conditions that investigate the recovery mechanisms of chemical flooding in a heavy oil reservoir. In the study, bench tests, including the phase behavior test, rheology studies and interfacial tension measurement are performed and reported for the optimum selecting method for the nano-emulsion which is going to be applied in the coreflooding experiments. Specifically, nanoemulsion systems have been mixed with Alaska North Slope West Sak heavy oil with 16 API°, which was dewatered in the laboratory condition, to investigate the rheology change during this process.
The experiment results suggest that the potential application of this kind of emulsion flooding is a promising EOR process for some heavy oil reservoirs in Alaska, Canada and Venezuela after primary production. Heavy oil lacks mobility under reservoir conditions and is not suitable for the application of the thermal recovery method because of environmental issues or technical problems.
The idea of nano-particle application in an EOR area has been recently raised by researchers who are interested in its feature- reaction catalysis-which could reduce in situ oil viscosity and generate emulsion without surfactant. Also, the nano-particle stabilized emulsions can long-distance drive oil in the reservoir, since the nano-particle size is 2-4 times smaller than the pore throat.
In conclusion, the nano-emulsion can be an effective enhancement option for an oil recovery method in a heavy oil reservoir which is technically sensitive to the thermal recovery method.