A Comparative Study on Operational Performance of Advanced Low Friction Residue-Free Fracturing Fluid versus Conventional Fluid Systems

Abstract

This paper compares the operational performance of a newly developed low friction, nearly residue-free (LF-RF) fluid system to a conventional derivatized guar-based fluid system and an existing nearly residue-free (RF) fluid system. The RF system has provided increased well production in numerous applications; however, the system requires lower treating rates due to increased friction. During recent field operations, the LF-RF system surpassed previous treating rates, which were previously unattainable, while maintaining maximum fluid cleanup. The friction responses between the RF, LF-RF, and derivatized guar-based fluids were assessed through quantitative analysis of surface treating pressures. All comparisons between fluid systems were made between wells on the same pad with the same completion method. The wells used in this study were all located in the Denver/Julesburg (DJ) basin and pumped using the same hybrid treatment design. Along with field data, laboratory testing was conducted to compare the viscosity profiles of the LF-RF and derivatized guar-based fluid, which were used in the field. Guar-based fracturing fluids have long been the industry standard. However, these fluids produce insoluble residue on breaking, which can reduce proppant pack conductivity and adversely affect well production. The RF fluid is an ultraclean, proven system, which has been successfully pumped in more than 16,000 stages. This fluid leaves virtually no insoluble residue, which has led to increased production from unconventional reservoirs. Yet, the RF fluid tends to exhibit increased treating pressures compared to guar-based fluids, which might require lower treating rates during operations. Additionally, a higher gel loading is necessary with the RF fluid to achieve comparable viscosities to the guar-based fluids. The new LF-RF fluid system retains all the beneficial cleanup properties of the RF system, while providing improved friction reduction. Intervals pumped with the LF-RF fluid provided lower treating pressures compared to those pumped with RF fluid, even at increased treating rates. With the improved friction reduction verified, the LF-RF fluid was pumped alongside a derivatized guar-based system at 80 bbl/min; a rate well beyond that which the RF fluid is generally pumped. The LF-RF fluid successfully placed all proppant and had similar treating pressures to the derivatized guar-based system toward the heel of the well. The LF-RF fluid was also able to accomplish this using a gel loading comparable to the derivatized guar-based system. Through quantitative analysis of the surface treating pressures, the LF-RF system has demonstrated increased friction reduction compared to the existing RF system. The improved friction reduction allows the LF-RF fluid to be pumped at high rates, expanding the range of possible well and treatment designs which this fluid system can accommodate.