Reverse osmosis desalination: Modeling and experiment

An analytic model for the performance of reverse osmosis desalination systems is derived. Predictions are shown to agree well with extensive measurements conducted on a commercial multistage reverse osmosis desalination unit over a broad range of operating conditions. The model allows a transparent understanding of the dependence of system performance on key design and operating variables. Identifying the characteristic flow rate and length scale of reverse osmosis systems allows a universal description of the variation of the permeate flow rate and recovery factor with the salinity, flow rate, and pressure of the feedwater.