Metallurgy Division, Bhabha Atomic Research Centre, Trombay, Bombay-400 085 India
Abstract:
The choice of the gas distributor to bed pressure drop ratio for the stable operation of gas fluidised beds is determined by the type of gas distributor and by the characteristics of the bed material. A critical analysis regarding the choice of the ratio has been made and reasons for diverse views expressed in the literature have been offered. An equation to determine UM, the superficial gas velocity at which all the orifices in a distributor become operative in a uniformly fluidised bed has been suggested, i.e. where Umf and Ut are the minimum fluidisation velocity and the terminal velocity respectively. The distributor to bed pressure drop ratio (ΔPd/ΔPb) can be calculated from Umf and UM using the equation where the constant C equals 2.
