Improve performance of different types of drilling fluids using nanomaterials

Abstract

Deepwater drilling in offshore operations found negative impact on the drilling fluids rheological properties when exposed to high pressure high temperature (HPHT) conditions. Hence, designing drilling fluids for drilling in deep sea and HPHT wells are major challenge. The major drilling fluid properties to ensure the success under these conditions are rheology, fluid loss, mud cake thickness and lubricity. In this study, the impact of multi-walled carbon nanotube (MWCNT) and nano metal oxides (titanium oxide, aluminium oxide and copper oxide) on the rheological properties of drilling fluid were investigated. Adding a suitable amount of nanoparticles into drilling fluid is very important because it will affect the properties and behavior of drilling fluids. Thus, the influence of different concentrations of nanoparticles on rheological properties of water-based mud (WBM), sarapar-based mud (SBM) and ester-based mud (EBM) were investigated at room temperature and aging at 250°F and 16 hours. The experimental results show that the filtrate loss of the WBM is reduced around 65% and mud cake thickness is reduced about 30% in the presence of 1 g MWCNT. WBM and SBM with metal oxide also produced low filtrate loss. For example, WBM and SBM plus titanium oxide achieved more than 50% reduction in fluid loss and the mud cake thickness reduced to about 30%. However, the presence of nanoparticle in EBM resulted that no effect to filtrate loss and mud cake thickness. Furthermore, significant improvements are seen in the rheological properties such as yield point, plastic viscosity and gel strength of the WBM and SBM with the presence of metal oxide and MWCNT. Except titanium oxide, EBM with nanoparticle displayed slightly enchantment on rheological properties. Overall, the application of nanoparticles on the rheological properties of WBM and SBM delivers on great benefits compared to EBM.