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Catalyst pellets of 5 mm diameter are to be fluidized with 45,000 kg/h of air at...

Catalyst pellets of 5 mm diameter are to be fluidized with 45,000 kg/h of air at 1 atm and temp. 30 C in a vertical cylindrical vessel. The density of the catalyst particles is 850 kg/m3; their sphericity is 0.85. The given quantity of air is just sufficient to fluidize the solids. Determine the vessel diameter and terminal velocity. Show pressure drop versus superficial velocity characteristic curve showing both fixed and fluidized bed region. Assume void fraction (under fixed bed state) to be 0.38 and height of vessel is 4 times the diameter of the vessel.

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