Arabian Journal of Chemistry (Aug 2020)
Enhanced cuttings transport efficiency of water-based muds using (3–Aminopropyl) triethoxysilane on polypropylene-nanosilica composite
Abstract
The lifting of cuttings has been a challenging phenomenon in the petroleum industry for a long period, given the complexity of different cuttings types and their high tendency to gravitate to the low side of the hole. Although many additives have been applied to improve the efficiency of water-based muds (WBMs) for cuttings transport, only a few success was recorded in the application of these additives once evaluated under different field situations. In this study, a new WBM formulated by nanocomposites was proposed to lift cuttings out of the annulus during drilling. Series of characterization, rheological, filtration loss, and cuttings transport tests were performed on the drilling muds formulated by (3-Aminopropyl) triethoxysilane modified polypropylene-silica nanocomposite (PP-SiO2 NC-NH2). The cuttings transport test was conducted in a 16-ft. annulus using 9.5 ppg muds, a 60°-hole angle, and annular velocities between 66.1 and 138.6 ft/min at different PP-SiO2 NC-NH2 concentrations of 0.4, 0.5, 0.8, and 1.2 ppb. The performance of 0.5 ppb PP-SiO2 NC-NH2 + WBM on CTE was evaluated and compared with that of WBM + 0.5 ppb of partially hydrolyzed polyacrylamide (PHPA) at five different hole angles from 90 to 0°. The results of zeta potential showed that the PP-SiO2 NC-NH2 was stable. The rheological and filtration properties were enhanced by the inclusion of PP-SiO2 NC-NH2 in the WBM. There exists a better enhancement in the CTE of PP-SiO2 NC-NH2 + WBM over that of PHPA + WBM at 0.5 ppb. The highest cuttings lifted to the surface occurred in a vertical well, followed by 90°, 30°, 60°, and 45° wells. An increase in annular velocity and the orbital motion of the drill pipe by mechanical action increased the CTE of the nanocomposite more than the rest mud samples. It seems the PP-SiO2 NC-NH2 can be more effective than the PHPA for the drilling process and can improve the cuttings lifting performance of WBMs but caution should be exercised to ensure its proper dispersion in drilling muds.
