Analyzing the spatial and temporal characteristics of membrane fouling

Fouling characteristics of crossflow flat-sheet membranes for two Nanofiltration (NF), one Ultrafiltration (UF), and one Microfiltration (MF) membranes were analyzed using 12.5 parts per million (mg/L) FeCl₃ solution and 350 mg/L copper nanofluid. FeCl₃ solution represents dissolved contaminant whereas copper nanofluid simulates particulate contaminant. The spatial and temporal fouling evolutions were captured using digital photography and analyzed using ImageJ software. FeCl₃ fouling studies for one NF membrane showed uniform fouling whereas for the other NF membrane, isolated fouling was apparent and the fouling initiated at the outlet then gradually extended towards the inlet. Copper nanoparticle fouling studies analyzed through gravimetric and image processing revealed spatial and temporal fouling developments. Both non-equilibrium and equilibrium fouling stages/regions were evaluated through fouling density analysis.