Experimental investigation of the influence of nanoparticles on water-based mud

This study has investigated the influence of nanoparticles including nanoparticle concentration, size, and type on waterbased mud (WBM) properties including rheology, filtration, and lubricity through experimental tests, while the influence of temperature and aging on these properties have been investigated. It has been found that adding SiO₂ nanoparticles increase the plastic viscosity and decrease the yield points and gel strengths with the increase of nanoparticle concentration. At fixed 0.5 wt%, the plastic viscosity decreases with the increase of TiO₂ nanoparticle size, but the influence of TiO₂ nanoparticle size on yield points and gel strengths is not monotonous. In general, adding negative charged SiO₂ nanoparticles reduce the yield points and gel strengths, while adding positively charged TiO₂, Al₂O₃, and Fe₃O₄ nanoparticles increase yield points and gel strengths. Adding lower concentrations (< 0.05 wt%) of SiO₂ nanoparticles improved mud filtration and lubricity properties, but higher concentrations are adverse to these properties and adding 0.5 wt% TiO₂, Al₂O₃ and Fe₃O₄ nanoparticles impaired these properties. Besides, it is found that there is no consistent influence of aging on mud properties and adding nanoparticles cannot improve aging resistance of mud. Although adding nanoparticles can significantly affect WBM properties, their influences are not consistency, depending on the integrated impact of the nanoparticle properties, such as surface electrical property, specific surface area, concentration, and size.