Design optimization of hollow fiber dialyzers to enhance internal filtration based on a mathematical model

• Published in: Journal of membrane science 2020-03, Vol.598, p.117690, Article 117690
• Main Authors: Donato, Danilo, Storr, Markus, Krause, Bernd
• Format: Article
• Language: English
• Subjects: Design optimization; Dialyzer; Internal filtration; Momentum transport
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2019.117690

The recent development of dialyzers equipped with medium cut-off membranes has made it possible to perform a new technique, termed expanded hemodialysis, in which the removal of middle molecular weight solutes from patients suffering from end-stage kidney disease is increased by enhanced internal filtration, without requiring complex setup and fluid reinfusion, as in hemodiafiltration. A systematic analysis of the effect of all dialyzer design parameters on the rate of internal filtration has not been reported yet. This makes it difficult to develop optimized dialyzers in which internal filtration rate is maximized to enhance convective transport of solutes from the patient's blood. In this paper, a mathematical model of transport recently developed is used to investigate the effect of the geometrical and transport-related dimensionless groups determining momentum transport in dialyzers, identified with dimensional analysis, on the rate of internal filtration. Model predictions show that filtration fraction can be maximized by increasing the value of the membrane pressure modulus and the packing density. Dialyzers design can be optimized for maximal filtration fraction by combining design parameters so that the values of the membrane pressure modulus and the packing density range between 0.39 and 0.42, and between 55% and 60%, respectively. [Display omitted] •Development of a 2D mathematical model to predict internal filtration in dialyzers.•Optimization of dialyzer design based on dimensionless groups.•Model validation with experimental results.•Effect of interplay among parameters on internal filtration is investigated.