Drilling fluid technology is one of the most targeted and developed technologies worldwide due to the increasing demand for deeper drilling and more complicated wells. Several studies have shown numerous improvements in the mud characteristics when using nanoparticles (NPs) as additives. This study aims at examining the influence of using aluminium oxide (Al₂O₃) and copper oxide (CuO) NPs on the characteristics of KCl-polymer mud, which is mainly used while drilling shaly formations. Two sizes of Al₂O₃-NPs (15 and 40 nm) in addition to CuO-NPs (40 nm) were investigated at different concentrations (0.1, 0.3, 0.5, 0.7, and 1.0 wt.%) using a standard viscometer and API filter press. Zeta potential (ζ-potential), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) were used to elaborate the effect of NPs on the properties of NPs-based KCl-polymer mud. The results showed higher potential of Al₂O₃-NPs and CuO-NPs to enhance the mud properties when used at small concentrations of 0.3–0.5 wt.%. Furthermore, NPs were found to play a key role in building efficient filter cakes with time during filtration (up to 90 min). Moreover, smoother surface morphologies and less porous structures of filter cakes were observed when using NPs with some agglomeration of CuO-NPs due to higher density. The Herschel-Bulkley model was found to provide a better fitting of the rheological data of NPs-based KCl-polymer mud than the Bingham plastic model. This approach would be able to virtually overcome any shale issue encountered by proactively plugging nanopores while inhibiting the water absorption in shale formations.

中文翻译：

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Al2O3 和 CuO 纳米颗粒作为改善氯化钾聚合物泥浆性能的有希望的添加剂：一项实验研究

由于对更深钻井和更复杂井的需求不断增加，钻井液技术是全球最具针对性和开发的技术之一。几项研究表明，当使用纳米颗粒 (NP) 作为添加剂时，泥浆特性有许多改进。本研究旨在研究使用氧化铝 (Al ₂ O ₃ ) 和氧化铜 (CuO) NPs 对主要用于页岩地层钻探的 KCl 聚合物泥浆特性的影响。两种尺寸的 Al ₂ O ₃- 使用标准粘度计和 API 压滤机研究了不同浓度（0.1、0.3、0.5、0.7 和 1.0 wt.%）下除了 CuO-NPs（40 nm）之外的 NPs（15 和 40 nm）。Zeta电位（ζ-电位）、扫描电子显微镜（SEM）和能量色散X射线光谱（EDX）被用来阐述纳米颗粒对纳米颗粒基氯化钾聚合物泥浆性能的影响。结果表明Al ₂ O _{3具有较高的潜力}-NPs 和 CuO-NPs 在以 0.3–0.5 wt.% 的小浓度使用时可增强泥浆性能。此外，发现 NP 在过滤期间（长达 90 分钟）随着时间的推移在构建高效滤饼方面发挥着关键作用。此外，由于较高的密度，当使用具有一些 CuO-NPs 聚集的 NPs 时，观察到滤饼的更光滑的表面形态和更少的多孔结构。发现 Herschel-Bulkley 模型比 Bingham 塑料模型更能拟合基于 NPs 的 KCl-聚合物泥浆的流变数据。这种方法实际上可以克服通过主动堵塞纳米孔而遇到的任何页岩问题，同时抑制页岩地层中的水吸收。