Heavy oil recovery by inert gas injection with horizontal wells

Gas injection is one of the oldest enhanced oil recovery techniques used for the recovery of light oils. Recently, there has been a growing interest in this technique for both light and heavy oil reservoirs. The application of gas injection to horizontal wells for the recovery of heavy oils from shallow reservoirs has been investigated using a 2D physical model. Oil recovery using gravity-stabilization may be as high as 70% of the oil-in-place for moderately viscous heavy oil reservoirs. The importance of maintaining a stable displacement front was demonstrated through several displacement tests under unstable as well as pseudostable displacement regimes. Unstable or pseudostable flow regimes are likely to prevail in the situation where gravity stabilization does not take place.