Patent ID: 8877693

Claim:
A method for breaking the viscosity of aqueous fluids gelled with a viscoelastic surfactant (VES) comprising adding to an aqueous fluid at least one VES in an amount effective to increase the viscosity thereof; adding to the aqueous fluid before or after the VES at least one internal breaker in an amount effective to reduce the viscosity of the gelled aqueous fluid, where the internal breaker is selected from the group consisting of mineral oils, hydrogenated polyalphaolefin oils, and saturated fatty acids; and adding to the fluid before, during or after adding the internal breaker, at least one oil-soluble surfactant breaker enhancer in an amount effective to accelerate reduction of viscosity of the gelled aqueous fluid, where the oil-soluble surfactant breaker enhancer is selected from the group consisting of sorbitan fatty acid esters, saponified hard oils, long chain alcohols, long chain fatty acid alcohols, long chain fatty amines, long chain sulfates, long chain sulfonates, phospholipids, and lignins, wherein the aqueous fluid does not include any other viscosity reducing agent.