In recent years, several studies have indicated the impact of nanoparticles (NPs) on various properties (such as viscosity and fluid loss) of conventional drilling fluids. Our previous study with commercial iron oxide NPs indicated the potential of using NPs to improve the properties of a laboratory bentonite-based drilling fluid without barite. In the present work, iron oxide NPs have been synthesized using the co-precipitation method. The effect of these hydrophilic NPs has been evaluated in bentonite and KCl-based drilling fluids. Rheological properties at different temperatures, viscoelastic properties, lubricity, and filtrate loss were measured to study the effect of NPs on the base fluid. Also, elemental analysis of the filtrate and microscale analysis of the filter cake was performed. Results for bentonite-based fluid showed that 0.019 wt% (0.1 g) of NPs reduced the coefficient of friction by 47%, and 0.0095 wt% (0.05 g) of NPs reduced the fluid loss by 20%. Moreover, for KCl-based fluids, 0.019 wt% (0.1 g) of additive reduced the coefficient of friction by 45%, while higher concentration of 0.038 wt% (0.2 g) of NPs shows 14% reduction in the filtrate loss. Microscale analysis shows that presence of NPs in the cake structure produces a more compact and less porous structure. This study indicates that very small concentration of NPs can provide better performance for the drilling fluids. Additionally, results from this work indicate the ability of NPs to fine-tune the properties of drilling fluids.

In recent years, nanomaterials have attracted researcher's attention especially in the field of oil and gas. Nanomaterials based research results showed an improved performance in the areas of cement, drilling fluid and enhanced oil recovery. In this study, the effects of Boron Nitride (BN) microparticles on mechanical friction, fluid loss and viscosity were investigated. Boron Nitride (BN) microparticles were dispersed in a solution of Carboxymethylcellulose (CMC) and Fe₂O₃ nanoparticles were dispersed in Xanthan gum (XG) solution in water. Both fluids were treated with KCl and bentonite to create laboratory drilling fluid systems, which were studied at 22 °C. The results show that the addition of 0.0095 wt. % BN and Fe₂O₃ reduced the mechanical friction coefficients of the laboratory drilling fluids by 37 %, and 43 %, respectively. Fe₂O₃ nanoparticles reduced the API static filtrate loss by 14.3 %, but the addition of BN didn't show any impact on filter loss. The particles have also shown an impact on the drilling fluid's viscosity parameters. The essence of this study is to understand the effect of nanoparticles on the drilling fluid performance and to get the better idea of how nanoparticles can contribute to improve the drilling fluid properties.

Bentonite-based drilling fluids are used for drilling, where inhibitive fluids are not required. The rheological and the density properties of the drilling fluids are highly affected by high temperature and pressure. Due to high temperature, the clay particles stick together, and the fluid system becomes more flocculated. Poorly designed drilling fluid may cause undesired operational issues such as poor hole cleaning, drill strings sticking, high torque and drag. In this study, the 80 °C thermally stable Herschel Bulkley’s and Bingham plastic yield stresses drilling fluids were formulated based on lignosulfonate-treated bentonite drilling fluid. Further, the impact of a MoS₂ nanoparticle solution on the properties of the thermally stable base fluid was characterized. Results at room temperature and pressure showed that the blending of 0.26 wt.% MoS₂ increased the lubricity of thermally stable base fluid by 27% and enhanced the thermal and electrical conductivities by 7.2% and 8.8%, respectively.

Recently the application of nanomaterial is attracting the oil and gas industry. The preliminary nanomaterials research results show an improving performance of cement, drilling fluid and Enhanced Oil Recovery. In this paper, the effect of nano Silicon dioxide (SiO₂) on polymer (HV-CMC, Xanthan gum, LV-CMC) and salt (KCl, NaCl) treated bentonite drilling fluid systems has been studied at room temperature. The results show that the performance of nano SiO₂ in bentonite mud system depends on its concentration and the types of salt and polymer systems used. In the considered fluid systems, it is also observed that the addition of about 0.06% SiO₂ influences rheology, and filtrate loss of the drilling fluid systems. The viscoelasticity of the selected best system further studied and their hole -cleaning and hydraulics performances are simulated. The overall result shows that the formulated optimum concentration of nano-system shows good performances and rheological behavior.