Design and performance evaluation of reverse osmosis desalination systems: An emphasis on fouling modeling

Sensitivity analysis was performed on different design and performance factors of a reverse osmosis system. In general, the most important design and performance parameter was the feed pressure and feed concentration, respectively. From the design point of view, it seems that, if newer technologies move toward decreasing the feed pressure to possibly save on pumping power requirement, the required membrane area may become much more sensitive to the feed pressure. In terms of performance, it was found that increasing the salt concentration of the feed for the range investigated, almost doubled the sensitivity of permeate concentration and water permeate flux to it. A model is proposed for predicting the normalized decrease in permeate flux due to fouling with two constants that have a robust interpretation. Results indicate that the model can predict the behavior accurately. •Normalized sensitivity analysis is done both for design and rating of an RO system.•Key design and rating parameters are found to be feed pressure and concentration.•Model for predicting fouling-induced normalized permeate flux decrease is proposed.•Two robustly interpreted model constants are explained from experimental data.•Results demonstrate that the model can predict the behavior accurately.