The use of electrospun flat sheet nanofibre membranes in MBR applications

The nonwoven nanofibre membranes in this study are made by the electrospinning technique. With a diameter ranging from 80 nm to several hundred nanometers, the nanofibres have a large surface area to volume ratio and a very high porosity. The aim of the study was to evaluate the use of nanofibre microfiltration membranes in three different membrane bioreactor (MBR) set-ups. More specific, in an active sludge MBR (AS-MBR), an AS-MBR with flux performing enhancer MPE50 and in a trickling filter MBR (TF-MBR). The results showed that the nanofibre membrane performed best with the TF-MBR. This was due to the removal of turbidity by the trickling filter, and also because of a new membrane module configuration. The flux was higher than the other configurations, and more important, the flux was stable for 85 days after which the experiment was stopped. Also different cleaning techniques with 0.5% NaOCl and 0.2% HCl were tested and compared in this study. The nanofibre membrane structure and strengths were not affected after the procedures for cleaning. Scanning electron micrograph (SEM) pictures show the nanofibre membrane being clean after 12 h of the alkali and acid treatment.