Recent Development in Hydrodynamic and Heat Transfer Characteristics in the Three-phase Fluidized-bed System


Gas–liquid-solid fluidized beds are broadly utilized in the petrochemical,pharmaceutical, refining, food, biotechnology, and environmental industries. Dueto complex phenomena, such as the particle-particle, liquid-particle, particlebubbleinteractions, complex hydrodynamics, and heat transfer of three-phase(gas-liquid-solid) fluidized beds, they are incompletely understood. The ability toaccurately predict the essential characteristics of the fluidized-bed system, such ashydrodynamics, individual phase mixing, and heat transfer parameters, isnecessary for its successful design and operation. This paper investigates thepressure drop, minimum fluidization velocity, phase holdup, heat-transfercoefficient of a fluidized bed reactor, heat transfer studies, CFD simulation, andthe effect of these parameters on the extent of fluidization. Many variables (fluidflow rate, particle density and size, fluid inlet, and bed height) affect the fluidizingquality and performance of the fluidization process. The hydrodynamicsparameters, mixing of phases, and the behavior of heat transfer with various modesof fluidization were investigated to predict hydrodynamics parameters. Severalpublications have demonstrated the utility of (CFD) in explaining thehydrodynamics, heat, and mass transfer of fluidized beds. Principles ofmeasurement, details of the experimental configurations, and the appliedtechniques by various researchers are also presented. Feng's model wasstatistically validated using experimental data that was both time-averaged andtime-dependent. Furthermore, this model successfully predicted the instantaneousflow structures, which should provide strategies for the best design, scale-up, andoperation in fluidized bed columns. The divergence between the simulated andobserved values can be reduced by better understanding the fluidized bed's nature.