HYDRODYNAMIC CHARACTERISTICS OF THREE-PHASE NONNEWTONIAN LIQUID-GAS - SOLID FLUIDIZED BEDS

The aim of this work is to study the hydrodynamic characteristics of three-phase fluidized beds.Such as gas- holdup, localgas- holdup, bubble rise velocity, minimum fluidization velocity,superficial gas velocity, the physical and liquid rheological properties. The experimental work ofgas-liquid-solid fluidized beds system was carried out in QVF glass column 0.106m I.D. and 2 mheight. A perforated teflone plate was used as gas distributor, with 53 holes , 7 mm diameter andfree surface area of 23.11%.Four of Carboxy Methyl Cellulose concentrations 0.1 %, 0.5 %, 1 %,and 2 wt%, were used as non-Newtonian (pseudoplastic) liquids. Air, O2 and CO2 were used withsuperficial velocity 0.03 -1.4 m/s. Activated carbon with diameter 0.25 -0.75mm and density 770kg/m^3 , Ni-Mo/Al2O3 with diameter 1.8 mm and density 2500 kg/m^3 were used as solid phase.The gas holdup was correlated with dimensionless groups and independent parameters withcorrelation coefficient is 0.9929, the following correlation is obtained.