Park Gun Woo, Nägele Gerhard
Institute of Biological Information Processing (IBI-4), Forschungszentrum Juelich GmbH, 52425 Jülich, Germany.
Membranes (Basel). 2021 Dec 6;11(12):960. doi: 10.3390/membranes11120960.
Cross-flow membrane ultrafiltration (UF) is used for the enrichment and purification of small colloidal particles and proteins. We explore the influence of different membrane geometries on the particle transport in, and the efficiency of, inside-out cross-flow UF. For this purpose, we generalize the accurate and numerically efficient modified boundary layer approximation (mBLA) method, developed in recent work by us for a hollow cylindrical membrane, to parallel flat sheet geometries with one or two solvent-permeable membrane sheets. Considering a reference dispersion of Brownian hard spheres where accurate expressions for its transport properties are available, the generalized mBLA method is used to analyze how particle transport and global UF process indicators are affected by varying operating parameters and the membrane geometry. We show that global process indicators including the mean permeate flux, the solvent recovery indicator, and the concentration factor are strongly dependent on the membrane geometry. A key finding is that irrespective of the many input parameters characterizing an UF experiment and its membrane geometry, the process indicators are determined by three independent dimensionless variables only. This finding can be very useful in the design, optimization, and scale-up of UF processes.
错流膜超滤（UF）用于小胶体颗粒和蛋白质的富集与纯化。我们探讨了不同膜几何形状对由内向外错流超滤中颗粒传输及效率的影响。为此，我们将我们近期针对中空圆柱形膜开发的精确且数值高效的修正边界层近似（mBLA）方法推广至具有一片或两片溶剂可渗透膜片的平行平板几何形状。考虑到布朗硬球的参考分散体系，其传输性质有精确表达式，利用广义mBLA方法分析了操作参数和膜几何形状变化如何影响颗粒传输及整体超滤过程指标。我们表明，包括平均渗透通量、溶剂回收指标和浓缩因子在内的整体过程指标强烈依赖于膜几何形状。一个关键发现是，无论表征超滤实验及其膜几何形状的输入参数有多少，过程指标仅由三个独立的无量纲变量决定。这一发现对于超滤过程的设计、优化和放大可能非常有用。
