A comprehensive review of nanoparticles: Effect on water-based drilling fluids and wellbore stability.

Wellbore stability in shale is a recurring crisis during oil and gas well drilling. The adsorption of water and ions from drilling fluid by shale, which causes clay swelling, is the primary cause of wellbore instability. Nanomaterials have been a subject of interest in recent years to be an effective shale inhibitor in drilling fluid, intending to minimize clay swelling. This article presents a comprehensive review of the current progress of nanoparticle role in water-based drilling fluid with regards to wellbore stability, reviewing the experimental methods, the effect of nanoparticles in drilling fluid, the mechanism of shale stability and the outlook for future research. This paper employed a systematic review methodology to highlight the progress of nanoparticle water-based drilling fluids in recent years. Previous studies indicated the current trend for drilling fluid additives was nanoparticles modified with surfactants and polymers, which minimize colloidal stability issues and enhance shale stability. A review of experimental methods showed that the pressure transmission test benefits shale stability assessment under reservoir conditions. Parametric analysis of nanoparticles showed that parameters such as concentration and size directly affected the shale stability even in high salinity solution. However, there is a lack of studies on nanoparticle types, with silica nanoparticles being the most popular among researchers. Nanoparticles enhance shale stability via physical plugging, chemical inhibition, and electrostatic interactions between surface charges. To better comprehend the influence of nanoparticles on shale stabilization, it is necessary to evaluate a wider range of nanoparticle types using the proper experimental techniques.