The occurrence of fouling conditions in heat transfer equipment of industrial enterprises causes the change of process regimes and can lead to full blockage of heat transfer channels. The investigation of fouling dynamics in plate heat exchangers (PHEs) is observed. The transport and reaction type of fouling model is used for accounting for the fouling on the heat transfer surface. The mathematical model of PHEs with commercially produced plates is presented. The model accounts for the difference in pressure drop and heat transfer coefficients along with the heat carrier movement through the channel distinguishing the major corrugated field, the zones of flow distribution, ports and collector part, introducing the local hydraulic resistances for each zone. The PHE performance in fouling conditions for different plate corrugations geometry is analysed. The impact of the corrugations’ inclination angle to the vertical plate’s axis on fouling dynamics is analysed for the case when PHE is assembled with plates of non-uniform corrugations angles. The results of the case study, represented by modelling of PHE installed in a sugar factory for heating a thin juice coming to an evaporation station, are presented. The approach for fouling mitigation at PHE design through the optimisation of plate corrugation geometry is discussed. The economic analysis showed, that the purchase of additional plates for operating PHE allows for saving 220 kW of heat energy and ensures reliable operation during 120 d of the sugar campaign.
Read full abstract