Cenovus Energy Inc.
Process for producing hydrocarbons from a subterranean hydrocarbon-bearing reservoir

Abstract:

A process for producing hydrocarbons from a subterranean hydrocarbon-bearing reservoir includes injecting a gas, at a pressure below a minimum miscibility pressure, into the reservoir through an injection well extending into the reservoir to form a gas zone in the reservoir. The gas injection pressure is suitable to provide a differential pressure between a bottom-hole production well pressure at a horizontal multi-lateral production well extending into the reservoir, and the gas injection pressure to facilitate sweeping the hydrocarbons toward the production well prior to gas breakthrough at the production well. The method also includes producing a portion of the hydrocarbons to surface through the production well, monitoring the production well for the gas breakthrough, and after the gas breakthrough is detected producing a further portion of the hydrocarbons by a gas gravity drainage process in which hydrocarbons are drained toward the production well, and controlling continued production of the hydrocarbons through the production well.