HYDRODYNAMIC STUDY OF GRANULATOR DISCS I - RESIDENCE TIME DISTRIBUTION AND AXIAL MIXING IN A ONE-CASCADE EQUIPMENT

The authors have investigated the residence time distribution of grain s in the rolling bed of a continuously operating granulator disc, cont aining cone-frustum and cylinder elements, with an inclined axle by fe eding (impulse disturbance) defined amounts of marked (coloured) subst ances. They have defined functions between the virtual, the C-function based and the reduced average (mean) residence time, and different pa rameters, such as the mass flow of grains, the rotation speed of the d isc at three different axial angles. Furthermore, they have investigat ed how the operating conditions might effect the calculated mixing coe fficient at predefined average residence time and known maximum concen tration of marked substances. Using the optimal parameters, intensive mixing conditions are produced in the rolling bed, in a similar way to the fluidised bed.