Patent ID: 8596357
Filing Date: 2013-12-03
Classification: E21B

Abstract:
1. A process for recovering hydrocarbons from an in situ formation wherein the process includes the step of: injecting steam through an injection well into an underground extraction chamber having a hydrocarbon extraction interface; warming the hydrocarbons at the extraction interface to cause the hydrocarbons to flow downwardly by gravity drainage and to release dissolved hydrocarbon gases, including hydrocarbon barrier gases; moving at least the hydrocarbon barrier gases away from the extraction interface to improve heat transfer from said steam to said interface, said step of moving at least the hydrocarbon barrier gases away from the extraction interface comprising adding a buoyancy modifying agent to said hydrocarbon barrier gases to cause said hydrocarbon barrier gases to rise in said chamber towards a top of said chamber, accumulating said barrier gases at a top of said chamber; and recovering said hydrocarbons through a production well.