Optimizing the Axial Resistance Profile of Submerged Hollow Fiber Membranes

Abstract

Submerged hollow fiber membranes (SHFMs) are used for a wide variety of applications. Their applicability and their advantages, however, depend crucially on the prevailing hydrodynamics within single fibers. In this respect, the non-uniform distribution of transmembrane flux is a known problem related to inhomogeneous membrane fouling and disadvantages for cleaning. To address this problem, we propose an approach to homogenize transmembrane flux by varying the local membrane resistance using optimal control methods for the first time in SHFM research. Based on an established model, different scenarios are optimized, namely with different fiber lengths and inner radii. In addition, a double-end setup is explored. It is shown that the optimization goal is reached very well in all tested cases, which underlines the general validity of our strategy. Further uses and extensions of the optimization method are provided, as well as hints for the practical implementation of the suggested measures.

Model‐based design of stratified packings for enhanced mass transfer using optimal control theory

“…Various examples of stratified packings have already been shown to have beneficial properties. 9,[11][12][13][14]17,18,23,42,43 Model-based methods are ideally suited to make optimal use of those benefits.…”

“…We are convinced that methods like those presented in this contribution will become increasingly important. Various examples of stratified packings have already been shown to have beneficial properties 9,11–14,17,18,23,42,43 . Model‐based methods are ideally suited to make optimal use of those benefits.…”

“…Kuhn et al 17 addressed the methodological gap in depth filtration by designing layered depth filters using optimal control theory. Kuhn and Briesen 18 applied the same methodology to the axial resistance profile of submerged hollow membranes. In addition to the beneficial properties of stratified columns, 3D printing has increased the possibilities of manufacturing such packings, allowing enhanced freedom of design 19–21 …”