The Effect of Silicon Dioxide Nanoparticle Functionalization on the Filtration Properties of Drilling Fluid and Porous Media Permeability

Abstract Near wellbore permeability alteration can hinder well productivity and injectivity performance. Drilling-induced permeability alterations frequently receive criticism because it is the first human action to disturb the formation's chemical and mechanical equilibrium. Despite various mitigating techniques, conventional overbalanced drilling with drilling fluid including colloid is still preferred because of its benefits for well control and wellbore stability. Current research trend focuses on engineering nanoparticles in drilling fluid to reduce extended fluid and solid infiltration into the formation. However, there is a fundamental knowledge gap regarding the effect of the nanoparticle surface properties on drilling fluid filtration properties. Due to the substantial difference in the surface-to-weight ratio in nano-sized materials, there is a distinct difference in the properties that govern matter at nanoscale as compared to those of the micro and macroscale. Consequently, surface properties play a more significant role for nanoparticles to work as filtration control material. Literature data suggest a relationship between nanoparticle charge and potential and drilling fluid filtration properties, albeit with limited discussion. Additionally, the effect of these properties on fluid and solid infiltration into porous media has not been studied. This research aims to study the effect of nanoparticle charge and potential on the drilling fluid filtration properties and porous media permeability. Silicon dioxide nanoparticles, functionalized with carboxyl and quaternary ammonium groups, were tested. Return permeability experiments on Berea sandstone core analyzed filtration properties and permeability alteration. The drilling fluid was water-based, and the formation fluid was sodium chloride brine. Results revealed that larger nanoparticle sizes produced a more consistent result, while smaller nanoparticles had better filtration properties but were more susceptible to change in other variables. Positively charged nanoparticles showed slightly better filtration properties but adversely affected return permeability due to strong adsorption onto sand particles. Permeability alteration was up to 89% for positively charged nanoparticles, compared to 53% for base drilling fluid, 83% for unfunctionalized nanoparticles, and 21% for negatively charged nanoparticles. This study provides insights into the significance of nanoparticle surface properties on drilling fluid filtration and transport in porous media, affecting permeability.