Tang Zhengjie, Huang Runzhou, Mei Changtong, Sun Xiuxuan, Zhou Dingguo, Zhang Xiuqiang, Wu Qinglin
College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China.
School of Renewable Natural Resources, Louisiana State University AgCenter, Baton Rouge, LA 70803, USA.
Materials (Basel). 2019 Jan 17;12(2):291. doi: 10.3390/ma12020291.
Performance of hardened oil well cement (OWC) is largely determined by the rheological properties of the cement slurries. This work was carried out to investigate the effect of water- to-cement ratio (WCR) and cellulose nanoparticles (CNPs), including cellulose nanofibers (CNFs) and cellulose nanocrystals (CNCs), on rheology performance of OWC-based slurries using a Couette rotational viscometer coupled with rheological models. The yield stress and viscosity of neat OWC slurries had a decreasing trend with the increase of WCRs. The suspension became increased unstable with the increase of WCRs. The properties of CNPs, including rheological behaviors, surface properties and morphology, determine the rheological performance of CNP-OWC slurries. In comparison with CNC-OWC slurries, the gel strength, yield stress and viscosity of CNF-OWC slurries were higher as CNFs were more likely to form an entangled network. The gel strength, yield stress and viscosity of CNP-OWC slurries increased with reduced CNF size through regrinding and the proportion of CNFs in the mixture of CNFs and CNCs, respectively.
硬油井水泥（OWC）的性能很大程度上取决于水泥浆的流变性能。本研究旨在使用Couette旋转粘度计结合流变模型，研究水灰比（WCR）和纤维素纳米颗粒（CNP），包括纤维素纳米纤维（CNF）和纤维素纳米晶体（CNC），对基于OWC的水泥浆流变性能的影响。纯OWC水泥浆的屈服应力和粘度随WCR的增加呈下降趋势。随着WCR的增加，悬浮液变得越来越不稳定。CNP的性质，包括流变行为、表面性质和形态，决定了CNP-OWC水泥浆的流变性能。与CNC-OWC水泥浆相比，CNF-OWC水泥浆的凝胶强度、屈服应力和粘度更高，因为CNF更有可能形成缠结网络。CNP-OWC水泥浆的凝胶强度、屈服应力和粘度分别通过再研磨减小CNF尺寸以及增加CNF在CNF和CNC混合物中的比例而增加。
