Patent ID: 6489270
Filing Date: 2002-12-03
Classification: C09K

Abstract:
A method for enhancing the thermal stability of a wellbore treatment fluid that includes polysaccharides, said method comprisingproviding a solids-free wellbore treatment fluid comprising a weighting agent, about 0.5 wt % to about 5 wt % polysaccharide, and a polyol selected from the group consisting of polyethylene glycol, poly(1,3-propanediol), poly(1,2-propanediol), poly(1,2-butanediol), poly(1,3-butanediol), poly(1,4-butanediol), poly(2,3-butanediol), and mixtures thereof, wherein the polyol has a number average molecular weight of about 190 to about 10,000; adding the wellbore treatment fluid to a wellbore; and maintaining a polyol concentration of greater than about 15 wt % polyol in the wellbore treatment fluid.