Influence of Sonication and Graphene Nanoplatelets Concentration on Rheological and Filtration Properties of Water-based Mud

The rising complexity of drilling under high-pressure and high-temperature (HPHT) conditions creates substantial challenges in fluid loss control, thermal stability, and rheological performance for drilling fluids. Nanoparticles, particularly graphene, have garnered tremendous attention as a promising additive to improve the performance of drilling fluids. This study investigates graphene nanoplatelets (GNPs) as a potential novel application to enhance the rheological performance and fluid loss control of WBMs. A comparative analysis of the impact of rheological performance, low-pressure, and low-temperature (LPLT) filtration test, high-pressure, and high-temperature (HPHT) filtration test is presented on WBMs with as-received and sonicated GNPs before tested with varying GNPs concentrations, ranging from 0.1 ppb to 0.5 ppb, under a 9 ppg mud weight. The samples were hot rolled at 250°F and 100psi for 16 hours to evaluate the influence of thermal aging on the properties of the GNPs water-based muds (WBMs). The experimental findings reveal that the mud with sonicated GNPs exhibits better performance, with 9.09% and 26.39% greater reductions in HPHT fluid loss and filter cake thickness, respectively. Besides, optimum concentration of 0.4ppb of GNPs results in a lower filtrate volume in HPHT conditions by 16.36%, and mud cake thickness in both LPLT and HPHT conditions by 17.08% and 21.44% respectively. The yield point has increased by 36.36%, while the plastic viscosity remains unchanged. Overall, this research demonstrates the capabilities of GNPs, particularly when sonicated, in enhancing the performance of WBMs, even at low concentrations, especially under HPHT conditions.