Influence of surface properties and characteristics on fouling in plate heat exchangers

The scope of the present work was to investigate the influence of surface properties of corrugated heat exchanger plates on calcium sulpate crystallization fouling from aqueous salt solutions. The applied surface treatment technologies for the heat exchanger plates are ion beam implantation, ion sputtering, carbo-nitriding & oxidizing, and Ni-P-PTFE coating. Ten pairs of Alfa Laval M3 heat exchanger plates were treated with these techniques and used for this study. Other process parameters such as temperature, solution composition, flow velocity, and the corrugation inclination angle of the plates were kept constant in order to allow for a comparison between the different surface treatments. To evaluate the influence of surface roughness on CaSO4 crystallization fouling, one pair of plates was electropolished. Surface energy and surface roughness measurements were carried out to characterize the treated surfaces.