Centrifugal classification of ultrafine particles: Influence of suspension properties and operating parameters on classification sharpness
Centrifugal classification of ultrafine particles: Influence of suspension properties and operating parameters on classification sharpness
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DOI：
10.1016/j.seppur.2015.06.015
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发表时间：
2015-12-17
影响因子：
8.6
通讯作者：
Nirschl, Hermann
中科院分区：
文献类型：
--
作者：
Konrath, Manuel;Brenner, Ann-Kathrin;Nirschl, Hermann
离心机分类的关键原理是轴向流速度和径向沉降速度的叠加，与颗粒大小有关。这些速度受可调参数的影响，因此，一定的粒度被定义为切割尺寸。因此，这种分离过程是由停留时间决定的。我们的研究解决了分类质量如何取决于过程的各种设置选项的问题。停留时间分布的实验测量和CFD模拟提供了流动状况的全面图景。除了确定速度分布外，后一种方法还用于直观地显示进给产品在转子中的分布。此外，根据一维对流粒子输运方程对选定产物的沉降行为进行了表征。固体浓度和稳定状态被考虑在内。将流场和沉降分析结果与分级实验结果进行了比较。(C) 2015 Elsevier B.V.版权所有
The key principle underlying classification in centrifuges is the superposition of an axial-flow velocity and a radial, particle size-dependent settling velocity. These velocities are influenced by adjustable parameters, whereby a certain particle size is defined as cut size. Therefore, this separation process is determined by residence time. Our study addresses the question as to how the classification quality depends on the various setting options of the process. Experimental measurements of the residence time distribution and CFD simulations provide a comprehensive picture of the flow conditions. Besides the velocity profile determination, the latter method is used to visualize the distribution of the product fed in the rotor.Additionally, a characterization of the sedimentation behavior of a selected product is made based on a one-dimensional convective particle-transport equation. Solids concentration and state of stabilization are taken into account. The findings of both flow field and sedimentation analysis are compared with the corresponding results from classification experiments. (C) 2015 Elsevier B.V. All rights reserved.