Question:

The figure below shows a packed bed in a 0.1 m diameter tube.  The particles are cylindrical in shape with surface volume mean diameter of 300 µm. The density and mass of the solids in the bed is 2000 kg·m^-3 and 5 kg respectively. Water with density of 1000 kg·m^-3 and viscosity 0.001 Pa·s flows upwards through the bed.

(a) Determine the void age of the packed bed.

(b) Determine the pressure drop when the bed is fluidized.

(c) Assume that the water flow is laminar, and the void age does not change, determine the minimum fluidization velocity.

(d) Show that the assumption in part (c) is correct.