Comparison of Zirconia Nanoparticles with Conventionally Used Silica Nanoparticles for HTHP Drilling Applications

Abstract

AbstractWell-designed formulations of drilling fluids are required for drilling operations to improve rheological and filtration properties. The rheological properties and fluid loss during the drilling process are severely affected at the deep well with high temperature and pressure conditions. This study investigates the comparison of zirconia nanoparticles and conventionally used silica nanoparticles on rheological and filtration properties at temperatures ranging from 76°F to 122°F. Sodium-bentonite dispersion in deionized water was used as the base drilling fluid.Rheological properties were determined at different temperatures using a Discovery Hybrid rheometer with various concentrations of nanoparticles from 0.2 wt.% to 0.75 wt.% concentrations. Steady shear rheology experiments were performed to study drilling formulations’ shear stress, viscosity, and yield stress. Temperature ramp rheology tests at 76°F and 122°F were performed to analyze the effect of increasing temperature on viscosity. The filtration tests were conducted to study the fluid loss properties of drilling fluids at various concentrations of nanoparticles. Linear swelling analysis of clay in the presence of drilling muds was performed to study the shale inhibition properties of prepared drilling formulations.The incorporation of nanoparticles significantly enhanced the rheological properties such as yield stress and viscosity at various concentrations and temperatures. Rheological properties of zirconia muds compared with silica muds for various concentrations of nanoparticles. Temperature ramp rheology tests showed that zirconia muds have enhanced viscosity at 0.75 wt.% compared to the counterpart of silica mud. A decrease in fluid loss was observed for zirconia muds compared to the base mud while fluid loss increases with increasing concentration of silica nanoparticles. The incorporation of nanoparticles in the drilling fluids significantly reduced the swelling of clay compared to the swelling of clay in deionized water.This research supports the extensive interpretation of water-based drilling fluids using zirconia nanoparticles and a comparison of drilling properties with silica-based fluids for high-temperature applications. The potential use of zirconia nanoparticles in drilling fluid formulations provides the way forward for the improvement of fluid loss characteristics, shale inhibition, and rheological properties.