Method of acidizing high-temperature subterranean formations

摘要

Subterranean formations at temperatures above 250 DEG F. are acidized by introducing a solution of a halogenated hydrocarbon and an organic solvent and allowing the halogenated hydrocarbon to hydrolyze in an aqueous medium to form a hydrohalic acid. Corrosion of metals, e.g., well casing, is inhibited by the presence of the solvent. The acidizing solution can be introduced as a liquid or as a mist in a substantially anhydrous gas. The aqueous medium can be naturally present in the formation or can be introduced into the formation as a liquid or as a foam simultaneously with the acidizing solution.