Mathematical model of variable volume diafiltration

Abstract

The use of ultrafiltration as a separation technique is frequently accompanied by a diafiltration step to remove microsolutes. There are different ways to combine ultrafiltration and diafiltration to obtain the desired final concentration of components. Variable volume diafiltration is a continuous process in which water is continuously added at a rate less than the permeate flow rate so that the concentration of macrosolute continuously increases, and the final concentrations of macrosolute and microsolute can be reached simultaneously. In this paper a mathematical model of variable volume diafiltration is proposed. The model includes both initial volume and concentration, rejection coefficients, processing time as well as water volume added during diafiltration. The developed model could be served for design and optimization purposes.