Effect of Magnetite Nanoparticles on Formation Damage Mitigation in Carbonate Rocks.

Nanoparticles have shown a potential to reduce formation damage and enhance drilling efficiency, though return permeability data remain limited in the literature. This study explores the incorporation of Fe3O4 nanoparticles into water-based drilling fluids as a strategy to reduce formation damage in carbonate reservoirs. Nanoparticles were synthesized and added to the base fluid at concentrations of 0.25, 0.5, and 1.0% (w/v). Comprehensive physicochemical and rheological characterizations were performed, followed by return permeability tests using Indiana Limestone cores under simulated reservoir conditions. The results demonstrated that the addition of 0.25% Fe3O4 significantly enhanced return permeability (83.2%) compared to the base fluid (70.7%) and reduced the flow initiation pressure from 10.7 to 6.1 psi. Despite an increase in filtrate volume at higher concentrations, the 0.25% formulation exhibited the optimal trade-off between filtration control (2.5 mL), filter cake quality, and return permeability. Statistical evaluation confirmed the significance of the observed improvements (p < 0.05). These findings demonstrate the potential of Fe3O4 nanoparticles to enhance drilling fluid performance and reduce reservoir damage.