May 18-22, 2003
Fouling of heat exchangers in dairy industries is still quite a severe problem both technically and economically. Altering the surface properties of the heating surfaces would be a way of solving this issue.
Modified steel surfaces were tested in an Alfa Laval V2 plate heat exchanger throughout dairy product sterilization. The behavior was analyzed for 8 different surface treatments, such as coatings (Diamond Like Carbon [DLC], Silica, SiOX, Ni-P-PTFE, Excalibur®, Xylan®) and ion implantation (SiF+, MoS2).
All fouling and cleaning experiments were carried out in standard and well-controlled operating conditions. After fouling, no significant difference could be seen between all the modified steels and the reference by statistical variance analysis. Cleaning efficiency of Ni-PPTFE appeared significantly the best. It could be suggested that the free surface energy plays a predominant role and the roughness a minor role in the level of fouling and cleaning efficiency.
M. Beuf, G. Rizzo, J. C. Leuliet, H. Müller-Steinhagen, S. Yiantsios, A. Karabelas, and T. Benezech , "Fouling and Cleaning of Modified Stainless Steel Plate Heat Exchangers Processing Milk Products" in "Heat Exchanger Fouling and Cleaning: Fundamentals and Applications", Paul Watkinson, University of British Columbia, Canada; Hans Müller-Steinhagen, German Aerospace Centre (DLR) and University of Stuttgart; M. Reza Malayeri, German Aerospace Centre (DLR) Eds, ECI Symposium Series, (2003). http://dc.engconfintl.org/heatexchanger/14