The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 12, 1986
Filed:
Dec. 17, 1981
Peter J Young, Calgary, CA;
Julian M Romocki, Calgary, CA;
Amerigo Technology Limited, Calgary, CA;
Abstract
There is disclosed a method of treating a subterranean substantially carbonate-free sandstone formation associated with a well completed in said substantially carbonate-free sandstone formation comprising displacing into said formation through said well an effective amount of an acidic aqueous solution comprising from about 5 to about 36 weight % phosphoric acid, from about 0.6 to about 5 weight % of a highly polar surface active agent which is a citric acid-monoethanolamine elimination reaction product, and an effective amount of a ferrous metal corrosion inhibitor. For treating a subterranean limestone or dolomitic formation or a sandstone formation having a substantial carbonate content there is additionally included in the acidic aqueous solution an amount of a phosphate crystal modifying agent sufficient to control crystal growth, minimize crystal agglomeration and minimize crystal adhesion to the formation. The acidic aqueous solutions exhibit clay shrinking and/or stabilizing properties and a lengthy spending time relative to that of conventional hydrochloric acid-based acidizing compositions.