Assessment of the design parameters for wastewater treatment by reverse osmosis

A modelling procedure is presented to predict the fluxes and solute concent rations in different flows for reverse osmosis (RO) spiral-wound modules. I mportant underlying factors for this procedure are the osmotic pressure for various solutions, the hydrodynamic flow profile in the concentrate channe l, and the intrinsic separation characteristics of the membrane material. E xperiments were carried out using a flat sheet test cell to determine the p arameters of the mass transport model. Results of residence time distributi on (RTD)-measurements on an industrial spiral-wound module were used to det ermine macroscopic fluid flow regimes resulting in the definition of dead v olume fraction, average residence time and Pe-number. The evaluation of the modelling procedure has been based on experimental data of an industrial m embrane plant system. (C) 1999 IAWQ Published by Elsevier Science Ltd. All rights reserved.