Application of MFI-UF on an ultrapure water production system to monitor the stable performance of RO process

Abstract

Despite significant advances in reverse osmosis (RO) applications, membrane fouling is an inevitable problem that reduces the quantity and quality of produced water and is associated with reducing the energy efficiency of the entire system. The aim of this study was to expand our understanding of the modified fouling index (MFI), which is a reliable tool used to provide insight into the fouling characteristics of the RO process in advance. The applicability of MFI to predict RO membrane performance was verified using a 50 m3/day pilot-scale ultrapure water (UPW) production plant study. The correlation between MFI and RO membrane performance (i.e., ∆(differential pressure)) was well validated based on seven months of pilot operation data. MFI-UFflux-10kDa was selected as a proxy for the fouling potential measurement according to the target process (or source water) to support the stable operation of UPW plant applications. Case studies including sensitivity analyses and electrochemical deionization (EDI) concentrate reclamation have verified the intimate correlation between the MFI and RO performance. The results from the current study are expected to provide practical insight and technical guidelines for RO-based plant engineers/operators.