July 1-6, 2007
The adhesion of bacteria and proteins on the surfaces of heat exchangers and food processing equipment has been recognized as a widespread problem. Biofouling not only reduces heat transfer performance significantly, but also causes considerable pressure drop, calling for higher pumping requirements. Biofouling also present a considerable hygiene risk in the food industry. It would be much more desirable if surfaces with an inherently lower stickability for biofouling could be developed. In this paper, stainless steel 304 plates were modified by electroless plating Ni-P and small amounts of PTFE. The experimental results showed that the surface free energy of the Ni–P–PTFE coatings, which were altered by changing the PTFE content in the coatings, had a significant influence on the adhesion of bacterial, protein and mineral deposits. The Ni–P–PTFE coatings reduced the adhesion of these deposits significantly. The anti-fouling mechanism of the composite coatings was explained with the extended DLVO theory.
Q. Zhao, C. Liu, Y. Liu, and S. Wang, "BACTERIAL AND PROTEIN ADHESION ON NI-P-PTFE COATED SURFACES" in "Heat Exchanger Fouling and Cleaning VII", Hans Müller-Steinhagen, Institute of Technical Thermodynamics, German Aerospace Centre (DLR) and Institute for Thermodynamics and Thermal Engineering, University of Stuttgart, Germany; M. Reza Malayeri, University of Stuttgart, Germany; A. Paul Watkinson, The University of British Columbia, Canada Eds, ECI Symposium Series, (2007). http://dc.engconfintl.org/heatexchanger2007/33