Inventors:
Clyde G. Inks - Taylor MI
Assignee:
BASF Wyandotte Corporation - Wyandotte MI
International Classification:
E21B 4327
Abstract:
The output of an oil well is improved by supplying thereto an acidizing-gel composition which consists essentially of, for example, about 15 weight percent of hydrochloric acid, about 20 weight percent of a suitable nonionic gel-forming surfactant containing oxyethylene and oxypropylene units, a corrosion inhibitor to the extent needed, and the balance water. The polymer is of high molecular weight, and though the composition containing such polymer is fluid at the temperature prevailing at the surface, nevertheless it forms a gel at the relatively higher temperatures present in the oil-bearing rock formation under the ground. This makes it possible to exert increased pressure on the oil-bearing rock formation, and it contributes to the effectiveness of the acidizing treatment.