Numerical investigation of the membrane fouling during microfiltration of semiconductor wastewater

Abstract

Membrane fouling is a problem of vital importance in microfiltration. A numerical method was used to investigate the membrane fouling phenomenon during microfiltration of semiconductor wastewater. In the numerical model, the concentration-dependent physical properties were considered and a dynamically updating boundary condition was incorporated to deal with the flux variation with fouling resistance. The mechanism of suspension transition from liquid phase to gel phase was adopted to characterize the formation of membrane fouling. With this method, the flow field and the concentration distribution as well as the fouling resistance in the membrane module were obtained. The results revealed the mass transfer character in the concentration boundary layer and its influence on the formation of membrane fouling. The enhancement effect of cross-flow on membrane filtration was analyzed in terms of wall shear rate and dimensionless Peclet number. Agreement between the simulation and the experimental results demonstrated the applicability of this numerical method in evaluating membrane fouling during microfiltration.

Keywords:

• Cross-flow microfiltration
• Fouling resistance
• Computational fluid dynamics
• Membrane fouling

Acknowledgment

The financial support from the PhD Start-up Fund of Natural Science Foundation of Liaoning Province (No. 20121024) is greatly acknowledged.