Numerical Comparison of Prediction Models for Aerosol Filtration Efficiency Applied on a Hollow-Fiber Membrane Pore Structure

journal article in Web of Science

en

Hollow-fiber membranes (HFMs) have widely been applied to many liquid treatment applications such as wastewater treatment, membrane contactors/bioreactors, membrane distillation etc. Despite the fact that HFMs are widely used for gas separation from gas mixtures, their use for mechanical filtration of aerosols is very scarce. In this work, we compared mathematical models developed for prediction of air filtration efficiency applying them on the structural parameters of polypropylene HFMs. These membranes are characteristic of pore diameters of about 90 nm and high solidity, thus high potential for nanoparticle removal from air. Single fiber/collector and capillary pore approach were chosen to compare between models developed for fibrous filters and capillary-pore membranes (Nuclepore filters) based on three main mechanisms occurring in aerosol filtration (inertial impaction, interception and diffusion). The collection efficiency due to individual mechanisms differs significantly. The differences are caused by the parameters for which the individual models were developed, i.e. given values of governing dimensionless numbers (Reynolds, Stokes and Peclet number) and also given values of filter porosity and filter fiber diameter. Some models can be used to predict the efficiency of HFMs based on assumptions depending on the conditions and exact membrane parameters.

Hollow-fiber membranes (HFMs) have widely been applied to many liquid treatment applications such as wastewater treatment, membrane contactors/bioreactors, membrane distillation etc. Despite the fact that HFMs are widely used for gas separation from gas mixtures, their use for mechanical filtration of aerosols is very scarce. In this work, we compared mathematical models developed for prediction of air filtration efficiency applying them on the structural parameters of polypropylene HFMs. These membranes are characteristic of pore diameters of about 90 nm and high solidity, thus high potential for nanoparticle removal from air. Single fiber/collector and capillary pore approach were chosen to compare between models developed for fibrous filters and capillary-pore membranes (Nuclepore filters) based on three main mechanisms occurring in aerosol filtration (inertial impaction, interception and diffusion). The collection efficiency due to individual mechanisms differs significantly. The differences are caused by the parameters for which the individual models were developed, i.e. given values of governing dimensionless numbers (Reynolds, Stokes and Peclet number) and also given values of filter porosity and filter fiber diameter. Some models can be used to predict the efficiency of HFMs based on assumptions depending on the conditions and exact membrane parameters.

Hollow-fiber membrane; aerosol; filtration efficiency; interception; inertial impaction; diffusion

19.06.2018

MDPI

Basel, Switzerland

2079-4991

8

6

1–24

24