van Ommen J Ruud, Valverde Jose Manuel, Pfeffer Robert
J Nanopart Res. 2012 Mar;14(3):737. doi: 10.1007/s11051-012-0737-4. Epub 2012 Feb 10.
Nanoparticles (NPs) are applied in a wide range of processes, and their use continues to increase. Fluidization is one of the best techniques available to disperse and process NPs. NPs cannot be fluidized individually; they fluidize as very porous agglomerates. The objective of this article is to review the developments in nanopowder fluidization. Often, it is needed to apply an assistance method, such as vibration or microjets, to obtain proper fluidization. These methods can greatly improve the fluidization characteristics, strongly increase the bed expansion, and lead to a better mixing of the bed material. Several approaches have been applied to model the behavior of fluidized nanopowders. The average size of fluidized NP agglomerates can be estimated using a force balance or by a modified Richardson and Zaki equation. Some first attempts have been made to apply computational fluid dynamics. Fluidization can also be used to provide individual NPs with a thin coating of another material and to mix two different species of nanopowder. The application of nanopowder fluidization in practice is still limited, but a wide range of potential applications is foreseen. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11051-012-0737-4) contains supplementary material, which is available to authorized users.
纳米颗粒（NPs）被应用于广泛的过程中，并且其使用量持续增加。流化是可用于分散和处理纳米颗粒的最佳技术之一。纳米颗粒不能单独流化；它们以高度多孔的团聚体形式流化。本文的目的是综述纳米粉末流化的发展情况。通常，需要应用一种辅助方法，如振动或微射流，以实现适当的流化。这些方法可以极大地改善流化特性，显著增加床层膨胀，并导致床层物料更好地混合。已经应用了几种方法来模拟流化纳米粉末的行为。流化纳米颗粒团聚体的平均尺寸可以使用力平衡或通过修正的理查森和扎基方程来估计。已经进行了一些首次尝试来应用计算流体动力学。流化还可用于为单个纳米颗粒提供另一种材料的薄涂层，并混合两种不同种类的纳米粉末。纳米粉末流化在实际中的应用仍然有限，但预计有广泛的潜在应用。电子补充材料：本文的在线版本（doi:10.1007/s11051-012-0737-4）包含补充材料，授权用户可以获取。
