Dilute single and mixed solute systems in a spiral wound reserve osmosis module Part I: Theoretical model development

A model of a spiral wound reverse osmosis module for dilute single and mixed solutes in water, which accounts for the material balances, effect of mixing on mass transfer, and pressure drop throughout the module, has been developed. The membrane mass transport model, applicable at any point in the module, can be chosen independently of the design equations. Two membrane mass transport models are considered: the Kimura-Sourirajan Analysis (KSA) and the Modified Finely Porous Model (MD-FPM). For no solute interaction the model is extended to include mixed solute systems. Simulations of reverse osmosis system performance are reported for a single solute case. In Part II the model is compared to experimental data for single and mixed organic solute systems.