Evaluation of chemical cleaning to control fouling on nanofiltration and reverse osmosis membranes after desalination of MBR effluent

In this study, the wastewater treated by the membrane bioreactor (MBR) process at the wastewater treatment plant of ITOB Organized Industrial Zone was used as the feed solution for further desalination by nanofiltration (NF90) and reverse osmosis (BW30) membranes. The effect of chemical cleaning to control the membrane fouling during long-term repeated uses of both NF and RO membranes were investigated. The water permeability values were obtained using deionized water as the feed solution after five cycles of desalination-membrane cleaning-permeability tests. Water permeability values changed from 3.93 L/m2·h·bar to 1.35 L/m2·h·bar for BW30 and 7.76 L/m2·h·bar to 2.65 L/m2·h·bar for NF90. The permeability tests were also carried out by using MBR effluent as the feed solution for better evaluation of fouling effects for MBR treated wastewater on desalination performance of NF and RO membranes. An optimal cleaning strategy was suggested throughout the study.