Mitigation of fouling of submerged hollow fiber membrane in microfiltration of TiO2 photocatalyst particles

Abstract

The subject of investigation is fouling of a polypropylene hollow fiber membrane by TiO2 catalyst particles, and mitigation of fouling during and after microfiltration. To remove or reduce fouling, two techniques were applied: backflushing (BF) and ultrasound (US). The fouling caused by the TiO2 particles is of the low extent, so the fouling resistances are more than twice lower than the resistance of the used membrane. From the flux stepping experiments, it was obtained that the critical flux is 60 l m–2 h–1. For the filtration below the critical flux, it is proved that application of back-flushing is more effective than the US, in removing a fouling cake layer which was already deposited on the membrane surface. Application of the US together with the filtration process was suitable for the prevention of fouling when it was applied from the beginning of the filtration process.