Fouling mitigation during product processing using a modified plate heat exchanger surface

Formation of foulants on food equipment surfaces causes reduction in the heat transfer as well as increase in the pressure drop across plate heat exchangers. Minimizing fouling is hence imperative to achieve better return on investment as well as to improve food quality. A plate heat exchanger (PHE) system operated in the recirculation mode was used to study the effect of surface-modified food processing equipment on fouling. Traditional SS-316 plates were coated with a novel coating (AMC-148-18), and the behavior of the coated plate in minimizing fouling as compared to the control SS-316 surface was studied. The PHE system was designed and installed in-house. Fluid skim milk and tomato juice at 5.5%) brix was pasteurized using the PHE system at a flow rate of 0.324 m ³ h ^-1. The product was circulated repeatedly through the heating and cooling sections of the PHE unit for about 6 h. At the end of the experimental period, the amount of fouling occurring in the coated surface were compared with the amount of fouling observed on stainless steel surface to determine the effectiveness of the new coated surface in controlling/minimizing fouling. The coated plate appeared to exhibit good adhesion qualities with the SS-316 substrate and could minimize the incidence of fouling by about 87% during skim milk pasteurization and by about 80% during tomato juice pasteurization. The high reduction in fouling observed (≥80%) could translate to increased energy savings and reduction in operation costs. Further tests are required for extended periods to strengthen the findings of the conducted experiments before implementing this technology in actual food processing plants.