Expanding the Degradable Fluid Loss Additive Application Spectrum Through Advanced Slurry Transport Modeling, Theoretical and Experimental Integration

Abstract

AbstractChemistry and the materials portfolio play a central role in fracturing success. Challenges in a achieving successful and productive proppant pack are resolved using varying products and fit-for-purpose chemistry utilization. The conventional understanding of using fluid loss additive (FLA) only for reducing fluid leakoff in high-permeability formations can be extended with advanced digital tools for optimum realization of a broader application spectrum for well-specific challenges.Polylactic acid-based powdered degradable FLA (DFLA) was developed with engineered particle size distribution to plug rock pore throats. Core flow tests were conducted with and without DFLA with borate crosslinked base fluid to measure the performance metrics. The application spectrum was extended beyond the fluid loss control in high-permeability rock to aid in screening out multiple fractures and natural fractures, reducing poroelastic tendency of tight, tectonically influenced formations. An advanced numerical modeling simulation approach was used to evaluate the distribution of the DFLA particles along the fracture cross-section and their dynamics to yield optimum fracture geometry with lesser pad volume.Coreflood tests demonstrated a reduction of up to 40% in fluid loss coefficient and spurt loss components with 30 lbm/1,000 gal DFLA loading. A regained permeability reduction of 12% from the baseline was observed when 25% particulate DFLA mass loss occurred, which can be minimized with higher shut-in times and complete degradation. The spectrum was expanded conceptually for up to eight applications based on literature references. Digitally advanced hydrodynamics and an in situ kinetics simulator were used to accurately model the slurry flow with and without DFLA. The model was extended with a sensitivity study with 32 synthetic cases to extend FLA utilization to medium- and low-efficiency formations. The modeling results showed that more than 50% of crosslinked pad volume could be saved while retaining the same fracture geometry evolution.Industry use of FLA chemistry has been minimal. In the digital age, this is the first and a unique demonstration of how digital tools can aid extending the material portfolio spectrum investigated from laboratory, simulation, and field case perspectives. Multiple applications of FLA can enhance project economics and reduce polymer and fracturing fluid formation damage by lowering the difference between differential pressure at the fracture face and drawdown during cleanup and the production phase.