Process for enhancing hydrocarbon mobility using a steam additive

摘要

A method for producing hydrocarbons from a subterranean formation comprises injecting steam and an additive into the formation. The additive has at least one nonaqueous fluid, which is selected so that the evaporation temperature of the additive is within about ±150° C. of the steam temperature at the operating pressure. Suitable additives include C1 to C25 hydrocarbons, and combinations thereof. At least a portion of the additive condenses in the formation. The mobility of the hydrocarbons is greater than that obtained using steam alone under substantially similar formation conditions.