CONCENTRATION POLARIZATION PHENOMENA IN TURBULENT-FLOW - REVIEW AND MODIFICATION

A theoretical modification have been developed to predict concentration polarization effects in a continuous reverse osmosis system by indirect measurements based upon the film theory. The modified model assumes that the actual rejection (Ra) is a function of the concentration at the membrane surface which varies with concentration polarization, a criterion not in general met by the previous studies. The results indicated that the existing model based on constant actual rejection (Ra) along the membrane surface tends to underestimate the solute build-up at the membrane surface while the modified model shows to be more capable and accurate to predict this phenomena.