Application of nano water‑based drilling fluid in improving hole cleaning

摘要

This paper presents a laboratory evaluation to study the effect of adding different nanoparticles on the rheological propertiesof water-based drilling fluids. Four different nanoparticles including aluminum oxide (Al_2O_3), magnesium oxide(MgO), titanium dioxide (TiO_2), and copper oxide (CuO) were added to a 7% bentonite water-based mud at two differentconcentrations; 0.5% and 1.5% by Vol. The rheological properties including plastic viscosity (PV), yield point (YP), andgel strength, were evaluated using a standard viscometer to quantify the effect of nanoparticle addition by comparingit to the reference drilling fluid containing 7% bentonite. In addition, a parametric study was conducted to betterunderstand the effect of the different parameters including rheological properties, hole size, flow rate, on hole cleaningefficiency. The results show that nanoparticles, in general, have a high potential in improving rheological propertieswhen compared to the reference point. A favorable reduction in the PV up to 50% along with an increase of 231% and95% in the YP and gels strength, respectively, were observed. The addition of nanoparticles has improved hole cleaningefficiency, when compared to the base case, for up to a maximum of 30% using 0.5% by Vol. of MgO nanoparticles. Also,an improvement by 67% in the hole cleaning was observed with 0.5% MgO for the largest cutting sizes when comparedto 7% bentonite. In general, MgO showed the highest improvement in hole cleaning, while TiO_2resulted in the lowestimprovement. The parametric study revealed that rheological properties along with the cutting size have the highesteffect on hole cleaning, while the effect of varying the flow rate was minimal when the rheological properties were high.Moreover, the effect of nanoparticles addition on hole cleaning was more pronounced for larger hole sizes with largercutting sizes when compared to the base case containing 7% bentonite only, which demonstrate the feasibility of usingnanoparticles to enhance the hole cleaning.