A concise analytical model for the ideal reverse osmosis desalination processes

Permeate recovery is a key parameter that plays a central role in the performance assessment and optimization of reverse osmosis processes. It remains a great challenge for engineers in the field to determine the recovery conveniently and accurately from the basic parameters of a membrane system. A concise analytical model is presented here that, without the need for the empirical or fitting coefficients and tedious numerical calculation, links the recovery of a reverse osmosis process rigorously to three basic parameters: the feed water salt concentration, the characteristic of membrane process, and the driving pressure. A graphical solution method to the model is also introduced to find out the recovery effortlessly. The concise model and graphical method are demonstrated under various conditions as a powerful tool for the performance simulations and improvement of reverse osmosis processes.Practitioner PointsA concise model is presented for permeate recovery in an ideal RO desalination system.The recovery of an RO system is analytically related to a few system parameters.A graphical solution method is introduced to find out the explicit recovery.The ideal RO model can be a powerful tool for simulation of RO processes. An analytical expression of the permeate recovery for a reverse osmosis desalination process is presented. It enables the determination of the recovery of the membrane system much more conveniently than the tedious numerical integration of permeate flux over the entire channel length of the process.image