Takata Kazutaka, Tanida Katsuyoshi
Department of Mechanical Engineering, National Institute of Technology, Kure College, 2-2-11, Agaminami, Kure 737-8506, Japan.
Technical Development Group, Kobelco Eco-Solutions Co., Ltd., 1-4-78, Wakinohamacho, Chuo-ku, Kobe 651-0072, Japan.
Membranes (Basel). 2022 Apr 14;12(4):422. doi: 10.3390/membranes12040422.
A high shear rate can be applied to fluid near a membrane surface by rotating the membrane. This shear rate enables higher permeate flux and higher concentration operation when compared with a conventional cross-flow membrane since fouling and/or concentration polarization are reduced. The purpose of this study was to clarify the relationship between the fluid behavior and membrane separation characteristics of a rotating membrane surface when a latex aqueous solution was used. Due to the synergistic effect of particle removal by the centrifugal forces generated by the rotation of the membrane and the reduction in the thickness of the velocity boundary layer, membrane filtration of high-concentration slurry, which is difficult to dewater by the cross-flow method, is possible. The experimental data using an aqueous latex solution with a wide range of slurry concentrations and various membrane diameters are well correlated using a shear rate derived from the boundary layer theory. It is thus confirmed that the shear rate can be used as a design and operating parameter to define the membrane filtration characteristics.
通过旋转膜,可以在膜表面附近的流体上施加高剪切速率。与传统错流膜相比,这种剪切速率能够实现更高的渗透通量和更高浓度的操作,因为污垢和/或浓差极化得以减少。本研究的目的是阐明在使用胶乳水溶液时旋转膜表面的流体行为与膜分离特性之间的关系。由于膜旋转产生的离心力对颗粒的去除作用以及速度边界层厚度的减小之间的协同效应,使得难以通过错流方法脱水的高浓度浆料的膜过滤成为可能。使用具有广泛浆料浓度范围和各种膜直径的胶乳水溶液的实验数据,通过边界层理论推导的剪切速率能很好地关联起来。因此证实,剪切速率可作为定义膜过滤特性的设计和操作参数。