Simulation of Viscous Fingering during WAG in Presence of Asphaltene

Asphaltene precipitation and VIscous fmgering are two serious problems
encountered during gas injection. The objective of this project is to study the effect of
asphaltene deposition on viscous fingering and oil recovery. This project includes
critical literature review and simulation work. The simulation work has been done using
a compositional oil simulator, CMG GEM. Two types of formation have been modeled;
without asphaltene deposition and with asphaltene deposition. Fluid flow through the
two formations has been simulated to observe viscous fingering that happens during
carbon dioxide (C02) injection and water-alternating-gas (WAG) injection. Results
show that presence of asphaltene slows down the propagation of viscous fingering and
production of oil. At a similar injected pore volume (PVI), presence of asphaltene does
not change the shape and size of viscous fingering during C~ injection but it slightly
changes the shape and size of viscous fingering during different types of WAG
injection. In addition, less fingering is observed at higher WAG ratio and severe
fingering is observed in the case of C02 injection and lower WAG ratio.