Abstract: An improvement in a process for dispensing a fluidizable solid from the lower portion of a pressure vessel equipped with a weighing device, a closable supply, a discharge, and a source of three gas flows, a first of which is applied within the vessel at a level above the solid to be fluidized, a second of which is applied within said vessel in a lower portion thereof, and a third of which is applied within the discharge orifice of the vessel, which discharge orifice terminates in a chamber, which improvement involves determining the amount of solid dispensed and determining the throughflow of gas in relationship to the amount of solid dispensed to maintain a constant gas/solid ratio while maintaining the pressures such that the pressure applied to the lower portion of the vessel is greater than the pressure applied at a level above of the solids which, in turn, is greater than the pressure applied to the discharge orifice, all of which are greater than the pressure maintained within the chamber, and an appara