Optimal Module Configuration and Sparging Scenario for a Submerged Hollow Fiber Membrane System

The present study characterized the surface shear forces induced by different sparging scenarios in full-scale hollow fiber membranes. Both continuous and intermittent (alternating between diffusers and on/off pulse to all diffusers) sparging was considered. For the optimal module configuration (i.e. configuration that was experimentally determined to generate the greatest surface shear forces), continuous sparging induced higher surface shear forces than alternating or pulse sparging. The difference between continuous and alternating sparging was observed to be due to an overall increase in the surface shear forces from the bottom to the top of the membrane system for continuous sparging, while the surface shear forces remained relatively constant throughout the depth of the system for intermittent sparging. Additional research is required to determine if the higher surface shear forces induced by continuous sparging can control fouling more economically than the lower shear forces induced by pulse sparging, which uses approximately half the sparging gas volume than continuous sparging.