| abstract |
An in situ extraction process for the recovery of hydrocarbons from a hydrocarbon bearing formation, including the steps of injecting a solvent consisting substantially of one of the group of H2S, Ammonia or COS into the formation to mobilize the hydrocarbons for extraction by forming a mobile in situ extraction fluid; and lifting the extraction fluid containing the mobilized hydrocarbons from the underground formation to the surface. In a further aspect an extraction method for a specific reservoir is provided including the steps of: establishing a minimum desired extraction rate, based on a value for the porosity, permeability and dead oil viscosity of the in situ bitumen in the specific reservoir, determining a desired minimum operating extraction temperature determining a desirable range of operating pressures identifying solvents predicted to deliver the operating extraction temperature within the range of operating pressures, and selecting a preferred solvent to use in the process. |