Method for enhanced recovery of petroleum
AssigneeTexaco Inc.
InventorsJohn H. Estes, Ernest P. Buinicky
Life of this patent
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Abstract
An enhanced oil recovery method comprising injecting an aqueous solution of ammonium salts selected from the group consisting of ammonium sulfite, ammonium bisulfite, and mixtures thereof into a petroleum-bearing earth formation, heating said injected aqueous solution to a temperature in the range of about 120.degree.-300.degree. F., or higher in the presence of said petroleum-bearing earth formation, flowing said heated aqueous solution through said petroleum bearing earth formation to drive petroleum to a recovery well, and producing increased amounts of petroleum from said earth formation through said recovery well.
Claims13
In a process for the recovery of petroleum oil from an earth formation penetrated by at least one injection well and by at least one recovery well spaced therefrom, the method which comprises:
- (a) injecting, via said injection well, an aqueous solution of an ammonium salt selected from the group consisting of ammonium bisulfite, ammonium sulfite, and mixtures thereof at a temperature less than about 120.degree. F. into said earth formation;
- (b) heating said injected aqueous solution to a temperature above about 120.degree. F.;
- (c) driving said heated aqueous solution from said injection well toward said production well for displacing petroleum oil from said earth formation;
- and
- (d) producing said displaced petroleum oil from said recovery well.
In the recovery of petroleum oil from an earth formation penetrated by at least one injection well, the method which comprises:
- (a) injecting, via said injection well, an aqueous solution of an ammonium salt selected from the group consisting of ammonium bisulfite, ammonium sulfite, and mixtures thereof at a temperature less than about 120.degree. F. into said earth formation;
- (b) heating said injected aqueous sulfite solution to a temperature about 120.degree. F.;
- (c) injecting a drive fluid, at an elevated pressure, into said injection well for driving said aqueous solution into said earth formation and displacing oil from the pores and interstitial spaces of said earth formation;
- (d) relieving pressure on said injection well such that displaced oil, said aqueous solution and other injected fluids flow from said earth formation to said injection well;
- and
- (e) producing petroleum from said injection well.
Dependencies are inferred from the claim text.