The Study of Dynamic Milk Ultrafiltration Performance Influenced by Membrane Molecular Weight Cut off

Document Type : Research Article

Authors

1 Department of Food Science and Technology, University of Ferdowsi, P.O. Box 91775-1163 Mashhad, I.R. IRAN

2 Department of Chemical Engineering, University of Wales Swansea, Singleton Park, Swansea, SA2 8PP, UK

Abstract

The effect of membrane molecular weight cut off (MWCO) at three levels (10, 20 & 50 kD) on dynamic behavior of permeate flux (JP), hydraulic resistances (total hydraulic resistance, RT; reversible fouling resistance, Rrf; irreversible fouling resistance, Rif and membrane hydraulic resistance, Rm) and milk solutes rejection (protein, RP; fat, RF; lactose, RL; minerals, RM and total solids, RTS) are studied for the ultrafiltration of milk. Experiments are carried out using the pilot plant UF membrane system equipped with a spiral wound module and a polysulfone amide membrane. A three-stage strategy based on a resistance-in-series model (boundary layer-adsorption) was used to determine the different hydraulic resistances. The results showed that the JP decreases greatly with increasing the process time, but the JP values obtained for 20 kD were considerably higher than 10 kD & 50 kD during the whole process. RT increased during operation at all levels of MWCO, but the hydraulic resistance values for 50 kD were significantly greater than 10 & 20 kD.  Results for milk solutes rejection showed that the RP and RF are almost constant with process time at the corresponding MWCO, whereas the RL, RM and RTS significantly increased.

Keywords

Main Subjects


[1] Rosenberg, M., Current and future applications for membrane processes in the dairy industry, Trends in Food Sci. & Tech., 6, 12 (1995).
[2] Razavi, S.M.A., Mortazavi, S.A. and Mousavi, S.M., Dynamic modeling of milk ultrafiltration by artificial neural network, J. Membrane Sci., 220, 47 (2003).
[3] Cheryan, M., “Ultraltration and Microfiltration Handbook”, 2nd edition,  Technomic Publishing Co., Lancaster, USA, (1998).
[4] Razavi, S.M.A., Mousavi, S.M.  and Mortazavi, S.A., Dynamic prediction of milk ultrafiltration erformance: A neural network approach, Chem. Eng. Sci., 58, 4185 (2003).
[5] Grandison, A.S., Youravong, W. and Lewis, M.J., Hydrodynamic factors affecting flux and fouling during ultrafiltration of skimmed milk, Lait, 80, 165 (2000).
[6] Eckner, K.F. and Zottola, E.A., Effects of temperature and pH during membrane concentration of skim milk on fouling and cleaning efficiency, Milchwissenschaft, 48, 187 (1993). 
[7] Cheryan, M. and Chiang, B.H., Performance and fouling behavior of hollow fiber and spiral wound ultrafiltration module processing milk, Engineering and Food, 1, 191 (1986).
[8] Kautake, M., Nabetani, H. and Matsuno, I., Influence of operation parameters on permeate flux in ultrafiltration of milks, Technical Research Institute, Snow Brand Milk Products Co. Ltd., Report No. 83, pp. 67-81 (1986).
[9] Patel, R.S. and Reuter, H., Fouling of hollow fiber membrane during ultrafiltration of skim milk, Milchwissenschaft, 40, 731 (1985).
[10] Kapasimalis, D.J. and Zall, R.R., Ultrafiltration of skim milk at refrigerated temperature, J. Dairy Sci., 64, 1945 (1981).
[11] Setti,  D. and  Peri,  C., Whey and skim milk ultrafiltration, 2. Parameters affecting permeation rate in skim milk ultrafiltration, Milchwissenschaft, 31, 466 (1976).
[12] Thompson, S.J. and deMan, J.M., Concentration and fractionation of milk by ultrafiltration, Canadian Institute of Food Science and Technology, 82, 113 (1975).
[13] Pompei,  C.,  Skim  milk  protein  recovery and purification by ultrafiltration, Influence of tem-perature on permeation rate and retention, J. Food Sci., 38, 867 (1973).
[14] Fenton, M.R.I., Concentration and fractionation of skim milk by reverse osmosis and ultrafiltration,
J. Dairy Sci., 55, 1561 (1972).
[15] Razavi, S.M.A., Mortazavi, S.A. and Mousavi, S.M., Application of neural networks for crossflow milk ultrafiltration simulation, International Dairy Journal, 14, 69 (2004).
[16] Ramachandar, R.H.G., Mechanisms of flux decline during ultrafiltration of dairy products and influence of pH on flux rates of whey and buttermilk, Desalination, 144, 319 (2002).
[17] Kautake, M., Matsuno, I., Nabetani H. and Nakajima, M., Classification of resistance to permeation caused by fouling during ultrafiltration of whey  and  skim  milk,  Bioscience,  Biotechnology  and Biochemistry,   56, 697 (1992).
[18]  Myong,  K. Ko. and Pellegrino, J., Determination of osmotic pressure and fouling resistances and their effects on performance of ultrafiltration membrane,  J. Membrane Sci., 74, 141 (1992).
[19] Roy,  N.K.  and Sen, D.C., “Textbook of practical dairy chemistry”, Kalyani Publishers Co., Ludhiana, India (1994).
[20] Modler, H.W., Functional properties of nonfat dairy ingredients; a review, modification of lactose and products containing casein, J. Dairy Sci., 68, 2195 (1985).