A method for recovering hydrocarbons from a reservoir includes separating air into a nitrogen-rich gas and an oxygen-rich gas, oxidizing a hydrocarbon fuel with at least part of the oxygen-rich gas to produce steam and a CO2-rich gas, injecting at least part of the steam through an injection well into the reservoir to heat the hydrocarbons, purging the injection well with at least part of the nitrogen-rich gas, and injecting at least part of the CO2-rich gas into the reservoir containing the heated hydrocarbons.