ABSTRACT
In the osmotic pressure model described by a number of authors flux reduction results from the decrease in the effective transmembrane pressure which occurs as the osmotic pressure of the retentate increases. One of the major obstacles that hinder widespread application of membrane separation for food processing is that the permeate flux declines with time—a phenomenon commonly termed as “membrane fouling.” “In-pore” fouling reduces processing rate and increases the complexity of membrane filtration operations, as the system has to be halted frequently to restore flux by periodic chemical cleaning. The effects of membrane pore size, membrane type, transmembrane pressure, temperature, solute concentration, and fluid velocity have all incorporated in a single model for the first time. The rate of flux decline is equal to the rate at which solids or solutes are brought to the membrane surface less the rate at which deposit is removed from the membrane.
