Methods of using strong acids modified with acid solutions
AssigneeAn-Son Petrochemical, Inc.
InventorDavid J. Martucci
Life of this patent
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Abstract
Acidic compositions comprising mixtures of hydrochloric, phosphoric, oxalic and citric acids, optionally additionally containing oleic, hydrofluoric or sulfuric acid and methods of preparing the acidic mixtures. Uses for certain mixtures of the acids include treating crude oil, in oil recovery processes, for well acidizing, cleaning glass, in batteries, removing corrosion from metals, removing oil residues from oil handling equipment and reactivating wells clogged with asphaltene.
Claims11
A method for acidizing wells surrounded by clay or silicate formations, said method comprising the steps of:
- (a) mixing water and hydrochloric acid with relatively smaller amounts of phosphoric, oxalic and citric acids and urotropine to form a first solution, said hydrochloric acid present in said first solution having a concentration of 1-60 percent by weight of said first solution, said phosphoric acid present in said first solution having a concentration of 0.2 percent by weight of said first solution, said oxalic acid present in said first solution having a concentration of 0.1-10 percent by weight of said first solution and said citric acid present in said first solution having a concentration of 0.1-25 percent by weight of said first solution;
- (b) forming a second solution by mixing a portion of said first solution with additional hydrochloric acid;
- (c) forming a third solution by mixing the remaining portion of said first solution with hydroflouric acid;
- (d) forming a fourth solution by mixing said second and third solutions;
- and
- (e) introducing said fourth solution into the well and into contact with the clay or silicate formations.
A method for acidizing wells surrounded by calcareous formations, said method comprising the steps of:
- (a) mixing water and hydrochloric acid with relatively smaller amounts of phosphoric, oxalic and citric acids and urotropine to form a first solution, said hydrochloric acid present in said first solution having a concentration of 1-60 percent by weight of said first solution, said phosphoric acid present in said first solution having a concentration of 0.2-60 percent by weight of said first solution, said oxalic acid present in said first solution having a concentration of 0.1-10 percent by weight of said first solution and said citric acid present in said first solution having a concentration of at least 0.1 percent by weight of said first solution;
- (b) forming a second solution by mixing said first solution with additional hydrochloric acid;
- and
- (c) introducing said second solution into the well and into contact with the calcareous formations.
Dependencies are inferred from the claim text.