Crosslinked DDG gels carry high proppant loads in low-temperature applications

Using commercially available double derivatized guar(DDG) gels as carrier fluid, operators may economically place large and heavily concentrated proppant loads into low-temperature formations. For the past 2 years, crosslinked DDG fluids have demonstrated superior economy by carrying high proppant concentrations with low gel concentrations. Temperature application ranges between 80-170/sup 0/F. Although a high level of research emphasis has been placed on development of crosslinked fracturing fluid systems for use in high-temperature applications, little research has been targeted for development of fluid systems to fracture low-temperature wells. New wells with bottom hole temperatures(BHT) above 200/sup 0/F. constitute a low percentage of total wells being drilled at this time, thus, the ratio of low-temperature wells being drilled would seem to dictate that fracturing fluid efficiency be optimized for these wells. Since technology requirements are not so critical for low-temperature wells, the greatest potential for improvement is in economy of creating and handling the fluid system. In field usage, DDG gels in concentrations as low as 25lb/1,000 gal have given adequate proppant-carrying characteristics for some applications. Extremely high proppant concentrations and large total proppant loads have been placed using the DDG gels. Fluid-system costs have been reduced as much as 37% using DDGmore » gels in lieu of conventional gel systems.« less