Study Of Protein Fouling On Heat Exchanger Surface And Anti-fouing

Fouling of heat exchangers is a severe problem because it reduces heat transfer efficiency and increases energy consumption and brings huge economic losses.Fouling on heat exchanger is comprehensive process including mass transfer,momentum transfer and energy transfer,affected by many factors,is one of the problems that haven't been solved.Thereby,research on protein fouling and anti-fouling method is of great significance.A real-time monitor system on fouling was used in present work to investigate the growth and cleaning processes of protein fouling on heat exchange.The effect of the heat flux,the surface temperature of heat exchange,the inlet temperature and aging time on the growth and cleaning processes of protein fouling were studied.Results have shown that fouling and cleaning behavior of soy protein isolate(SPI)was very different from that of whey protein concentrate(WPC).In addition,we try to find a suitable surface coating that with advantages of convenient and economy to reduce fouling.The effect of modified surface on protein fouling was investigated.Different coating materials were used to modified the heat exchanger surface include nafion solution,citric acid and surfactants(starch sodium octenyl succinate).The results showed that the surfactant coating that with pH=9 had no effect on the growth of WPC fouling,the surfactant coating that with pH=10 accelerated the growth of fouling only at the initial period.The citric acid coating had no effect on slow the growth rate of OVA fouling,however,the fouling layer was relatively loose compared to that of uncoated surface.As a result,it's very easy to clean.The nafion coating had obvious inhibitory effect on the growth of WPC fouling.