Patent ID: 6933262
Filing Date: 2005-08-23
Classification: C09K,Y10S

Abstract:
1. A method for prehydrating a water soluble polymer for addition to a brine for use in drilling and completion operations comprising: providing a precursor brine comprising an aqueous solution of a first salt at a first density, said first salt comprising cations consisting essentially of cations of one or more multivalent alkaline earth metals; and mixing said water-soluble polymer with said precursor brine at a first concentration and under first conditions, wherein said first density, said first concentration, and said first conditions are effective to produce a precursor polymer dispersion comprising particles of said water-soluble polymer at a level of prehydration; wherein, addition of a sufficient quantity of said precursor polymer dispersion to a final brine comprising an aqueous solution of a second salt at a final density produces a final polymer dispersion comprising a second concentration comprising final particles of said water-soluble polymer at a final level of hydration, said second concentration and said final level of hydration being effective at downhole conditions to maintain an effective level of a property of said final brine selected from the group consisting of rheology, fluid loss control, and a combination thereof.