This project aims to develop technologies for aqueous CO2 nanobubble (NB) dispersion for enhanced oil recovery from conventional and unconventional reservoirs. The central hypothesis in this project is that the CO2-rich phase generated near the fronts of oil displacement in CO2 NB injection can greatly enhance oil recovery. Previous studies on carbonated water injection (CWI) showed a markedly increased oil recovery factor upon breakthrough (RFBT) in comparison to the control experiment with brine with no CO2 when the CO2-rich phase was generated near the displacement fronts. CO2 NB is expected to promote this new mechanism of oil recovery by substantially increasing the CO2 concentration in water beyond the inherent solubility. Aqueous CO2 NB injection is also expected to be much simpler and less expensive than CO2 injection because a small amount of CO2 is injected as an effectively homogeneous aqueous fluid (e.g., 1 tonne of CO2 in 15 tonnes of brine).

The energy transition requires managing the global carbon balance with a large throughput of CO2 while shifting to less carbon intensive energy sources, such as hydrogen, in economically feasible, publicly acceptable ways. Many issues with processing CO2 and H2 come from their physical properties, their compression, transportation, and storage [e.g., H2 embrittlement]. Also, geological CO2 sequestration has various issues associated with the properties of CO2, such as low carbon density at low to moderate pressure, low mass density, low viscosity, immiscibility with water, and corrosivity [e.g., low pH near a CO2 plume]. In particular, CO2 injection often results in inefficient use of pore space in the formation under geophysical heterogeneities.