Design of cascade membrane filtration process for clarification of whey proteins and membrane fouling

Whey protein isolates are processed by membrane separation techniques - Micro-filtration, Nanofiltration and Ultra-filtration. Proteins, Glyco-macropeptide, Lacto-albumin, Lacto-globulin and Bovine Serum Albumin are collected by employment of 10, 30, 50 and 100 kilo-Daltons (kDa) ultra-filtration membranes, respectively based mainly on protein molecular weights. Pressure drop, trans-membrane pressure, flux and feed volume were optimized for lab scale. Volume and concentration values for all streams were calculated for micro-filtration, nano-filtration and 4 ultra-filtration membranes and satisfactory yield values were obtained. Through scale-up criteria, a cascade design has been proposed for pilot scale whose pressure values fall within the range of standard pressure values. Fouling studies were carried out in lab scale by calculating fouling and membrane resistances for all membranes and effect of anti-fouling chemical agents – SDS and NaOH on the membrane cleaning has been analyzed. The study has given on overall idea about the design corresponding to 6 membranes arranged in series to clarify 4 proteins from milk.