A Simple, Cost Effective Alternative to Crosslinked Guar Systems that Allows for the Use of Produced Water

Environmental concerns and increasing costs are creating a need for a polymer that will allow the use of a high salt, high hardness water in the making of a viscosified frac fluid. Any new polymer would also need to tick the boxes for cost, rheology, HS&E characteristics as well as breaking in the reservoir. Past development efforts have focused on improving organic-based polymers. A new approach was taken and a shift was made to the use of silica-based polymer. This paper will review silica chemistry but the focus will be on West Texas field trials where the silica gel was used as an alternative to 20 lb/Mgal crosslinked-guar. Covered topics will include; chemistry of produced water, making the silica gel on-location, pumping characteristics, cost and impact on production.