Hollow fiber membrane modules

•State-of-the-art in hollow fiber membrane module manufacture is described.•Structured fiber bundles offer higher mass transfer rates and lower pressure drops.•Non-ideal performance arises from flow maldistribution in shell and lumen.•Fiber size variability has largest effect followed by flow distribution in shell.

Hollow fiber membrane modules are used in a wide range of separation applications. Module design is critical to optimizing process performance. The state-of-the-art in fiber bundle and module manufacture is reviewed emphasizing industrial practice as reflected by the patent literature. Sources of non-ideal module performance are identified that arise from non-uniform module flows. Efforts to quantify these effects and evaluate design alternatives to improve performance are reviewed. Despite this work, gaps in understanding the relationship between design and performance still exist.