Enhancement of rheological properties of Bentonite waterbased muds by metal oxide nanoparticles

Exploration of oil/gas deep wells is increasing rapidly due to Global energy demands. Since the wells drilling operation is the primary stage to reach to the reservoirs hydrocarbon fluids, a successful well drilling operation causes the efficiency of hydrocarbon recovery to promote effectively. In this regard, drilling fluids play the main role in the success of drilling operations. It should be noted that, one of the main costs fordrilling of a well relates to the drilling fluids. Thus, utilizing drilling fluids with higher operational efficiency especially at high temperatures and pressures as well as lower cost investment is always in demand. In this study, the effects of various hydrophilic nanoparticles (NPs) namely aluminum oxide (Al2O3), titanium dioxide (TiO2), silicon dioxide (SiO2) and copper oxide (CuO) on the rheology of a water-based mud drilling wereexperimentally determined. For this aim, the NPs were utilized at concentrations of 0.01, 0.05, 0.1 and 1wt%. The results revealedthat the Al2O3 NPs increased the amount of mud filtration up to 80%. In contrast, the amount of mud filtration had a decreasingtrend when SiO2, TiO2 and CuO NPs were applied especially at the concentration below 0.5wt%. Besides that, other propertiessuch as yield point, plastic viscosity, and gel strength were improved in the presence of TiO2, Al2O3 and CuO NPs ascompared to the based. TiO2 followed by CuO NPs depicted a better improvement in the mud rheology compared to Al2O3. Itshould be noted the rheology of based mud almost remained unchanged when SiO2 NPs were used. Generally, we found thatapplying these NPs with water based-muds in concentrations below 0.5wt% leads to improving the muds rheology.

Keywords:

Nanoparticles , water-based mud , Rheological properties