Abstract:

The impinging stream has widely applied in chemical reaction, crystallization, preparation of ultrafine powder,etc. Due to its excellent characteristics of strengthening micro-mixing. Based on the mixing and strengthening characteristics of impinging stream technology, the recent research on the preparation of ultrafine powders in several impinging stream reactors was reviewed. The effects of fluid flow, confined space, nozzle form and structure, external excitation and other factors about the mixing performance on submerged circulative impinging stream reactor, confined impinging stream reactor, T-type impinging stream reactor, micro impinging stream reactor and impinging stream-rotating packed bed reactor were briefly described. The effects of micromixing characteristics of impinging stream on chemical reaction and preparation of ultrafine powder were analyzed from the aspects of crystallization and micromixing time. Compared with conventional reactors and methods, it was evaluated from the particle size, morphology, surface, energy, dispersibility, electrical properties and stability of ultrafine powders. An intermediate experiment of a two-layer opposed impinging stream reactor for industrial large-scale preparation of ultrafine powders was proposed, and the prospect of impinging stream technology for preparing ultrafine powders was prospected.

Key words: impinging stream, powder, mixing, crystallization, reactors

摘要：

撞击流以其强化微观混合的优异特性在化学反应、结晶、制备超细粉体等方面有广泛应用。本文在撞击流技术强化混合特性的基础上对近年来几种撞击流反应器制备超细粉体研究进行了综述。简述了流体流动、受限空间、喷嘴形式及结构、外部激励等因素对浸没循环撞击流反应器、受限撞击流反应器、T形撞击流反应器、微小型撞击流反应器、撞击流-旋转填料床反应器混合性能的影响。从结晶、微观混合时间等角度分析了撞击流微观混合特性对化学反应及制备超细粉体的影响。并与常规反应器及方法对比，从超细粉体的粒度大小、形貌、表面、能量、分散性、电性能及稳定性等方面进行评估。提出一种双层对置撞击流反应器用于工业上大规模制取超细粉体的中试研究，并展望了撞击流技术用于制备超细粉体的前景。

关键词: 撞击流, 粉体, 混合, 结晶, 反应器