Patent ID: 7718584

Claim:
A viscoelastic surfactant fluid comprising an aqueous fluid, a viscoelastic surfactant selected from the group consisting of methyl ester sulfonates, hydrolyzed keratin, taurates, amine oxides, ethoxylated amides, alkoxylated fatty acids, alkoxylated alcohols, ethoxylated fatty amines, ethoxylated alkyl amines and combinations thereof, and a dual-function additive that comprises about 2 pounds to about 30 pounds per thousand gallons of a soap component selected from the group consisting of sodium stearate, potassium stearate, ammonium stearate, sodium laurate, potassium laurate, sodium myristate, potassium myristate, sodium palmitiate, potassium palmitiate, calcium caprylate, sodium caprylate, potassium caprylate, sodium behenate, potassium behenate, ammonium behenate, behenic acid, capric acid, caprylic acid, dihydroxystearic acid, dotriacontanoic acid, eicosanoic acid, heptadecanoic acid, hexacosanoic acid, lauric acid, myristic acid, nonadecanoic acid, nonanoic acid, octacosanoic acid, palmitic acid, pentadecanoic acid, pentatriacontanoic acid, stearic acid, tetracosanoic acid, tetratricontanoic acid, tricontanoic acid, tridecanoic acid, tritriacontanoic acid and combinations thereof.