Patent ID: 6177385
Filing Date: 2001-01-23
Classification: C09K,Y10S

Abstract:
A well treating fluid comprising:(a) an aqueous hydrated galactomannan gum;(b) a buffering agent effective to provide alkaline buffering at the effective crosslinking pH comprising a weak acid and a salt of said weak acid, in an amount sufficient to provide a controlled alkaline pH of from about 9 to about 11 in the fluid;(c) a crosslinking boron releasing agent capable of furnishing boron ions, borate ions, or mixtures thereof, in solution for crosslinking said galactomannan gum;(d) the well treating fluid being effective at reduced concentration levels of galactomannan gum comprising from about 10 to about 30 pounds of aqueous hydrated galactomannan gum per 1000 gallons of fluid;(e) further wherein the fluid is effective to delay release of boron ions, borate ions, or mixtures thereof while facilitating a sufficiently elevated concentration level of boron ions, borate ions, or mixtures thereof to allow the effective use of the fluid at temperatures in excess of 175.degree. F.