Real time fouling monitoring with Electrical Impedance Spectroscopy

The impedance spectra obtained following macromolecular (BSA and molasses wastewater) fouling was found to be significantly different from those obtained with colloidal (silica) fouling. The decrease in capacitance observed for BSA and molasses wastewater, suggests the formation of a gel like layer on the membrane surface, while the increase in capacitance of the silica suggests a loose cake which enhances concentration polarization. Hence EIS may also be capable of indicating the type of fouling which is occurring at the membrane surface.