Liquid holdup and heat transfer coefficient between bed and wall in liquid solid and gas-liquid-solid fluidized beds

In fluidized beds of 0.052 and 0.12 m i.d. air, water and aqueous solutions of carboxymethyl cellulose (viscosity = 9.0 X 10-4- 52 X 10-2 Pa s), and glass beads were used as gas, liquid and solid phase, respectively. The diameters of the glass beads were 4.2 X 10-4 6.6 X 10-4 1.2 X l0-3, and 2.2 X 10-3 m. The liquid holdup in the gas-liquid-solid fluidized bed was well correlated by modifying the Garside and Al-Dibouni's equation with the gas phase Froude number. The wall heat transfer coefficient of the gas-liquid-solid fluidized beds in the range of stable fluidization state runs correlated as a function of modified Nusselt number, modified Reynolds number and gas phase Froude number.