This study focuses on the optimisation of submerged hollow fibre membrane performance by analysing the role of air sparging in the reduction of membrane fouling. In submerged hollow fibre membranes, rising bubbles have been shown to induce shear, liquid movement and fibre displacement. The interaction between fibre movement and the microfiltration performance was assessed for various parameters. Since energy consumption for aeration is a major contributor to the cost in submerged membranes, the potential to minimise the aeration cost has been tested by implementing intermittent aeration and different nozzle sizes. An attempt to suppress fouling without aeration was made by incorporating vibrations into a submerged membrane system. Results from the study suggest that bubble-induced fibre movement plays an important role in controlling membrane fouling. Investigations of the critical flux at various operating conditions also supported these conclusions. Furthermore, potential filtration enhancement could be achieved by applying vibrations to the system.

Autorentext

received a PhD degree in chemical engineering from the University of New South Wales, Australia and a master degree from Imperial College London. Currently, she is a research fellow at Singapore Membrane Technology Centre, Nanyang Technological University.