Enhanced cutting transport performance of water-based drilling muds using polyethylene glycol/nanosilica composites modified by sodium dodecyl sulphate

Abstract

Reports from drilling oil and gas fields show that wellbore problems like difficult pipe tripping, increased bit wear, differential pipe sticking, too much torque and drag, and lost circulation still persist. This is especially true when drilling highly angled and horizontal sections of the well, where the cuttings tend to settle on the bottom and lower sides of the hole. Even though water-based mud (WBM) additives like polymer nanocomposites have been used to surmount these problems, they still occur. This is because of the significant pressures resisting the passage of cuttings from the annulus to the surface. So, this study examined how the weight concentrations of modified polyethylene glycol/nanosilca composites (PEG/SiO2+SDS) affect the cutting transport efficiency (CTE) of WBM. The composite was modified with sodium dodecyl sulphate (SDS). Silica nanoparticle (SiO2 NP) and PEG/SiO2+SDS weight concentrations in WBM were compared on how efficiently they perform in cuttings transport. The drilling fluids transported four ranges of cuttings with diameters between 0.50 and 4.00 mm through a cuttings transport flow loop. The configuration of the flow loop is 0.061 m × 0.0305 m, with a 4.9 m-long annulus. Other test parameters are 0°, 45°, 60°, and 90° hole angles, flowrates of 4.17, 5.83, 7.50, 9.17, and 10.83 L/s, and 0.5, 1.0, 1.5, and 2.0 g weight concentrations of PEG/SiO2+SDS and SiO2 NP. For the cutting transport experiment, 1.5 g PEG/SiO2+SDS and 1.0 g SiO2 NP were the best choices. At 25 °C, the composite increased the viscosity by 60% and decreased the fluid loss by 47%, whereas SiO2 NP increased the viscosity by 20% and reduced the fluid loss by 9.8%. Overall, the composite cutting removal effectiveness is 20–48% greater than that of the base mud, whereas nanosilica is 11–37% greater. The composite has better rheology and more interparticle and colloidal interactions with cuttings than the NP. Viscosity makes it easier to carry small and intermediate-size cuttings than bigger ones, which need a higher flowrate. Following 60° hole inclination were 45°, 90°, and 0° in order of lowest CTE. This indicates that a 60° hole inclination requires special consideration while developing drilling fluids. These findings are particularly useful in understanding the CTE of nanocomposites at different concentrations. Also, it helps validate the superior drilling fluid performance of nanocomposites over nanoparticles.