Michael A. Smith, Jeff Dawson, Dan Scoggins; Dresser Titan, Dresser Industries, Inc.
Fracture acidizing systems previously available are acid and temperature sensitive. This paper will discuss a new crosslinked acid system that is compatible with up to 28% HCl and that has been successfully pumped at bottom hole temperatures to 250_F. Fluid rheology, friction pressure, fluid loss, additive compatibilities and acid reaction rates supporting the use of this system at 50 and 60 lbs./gal. polymer loadings are presented. Computer designs for acid fracturing and reservoir simulation are included in the paper to show the effects of the stable crosslinked acid compared to other available systems. This system has been used both with and without proppant. The acid concentrations have ranged from 3% to 28% HCl and where applicable sand concentrations from 2 to 6 lbs. per gal. have been successfully placed. Field data is presented for both producing and water injection wells. -