Liquid distribution as a means to describing the granule growth mechanism

Mapping of regimes for the key processes in wet granulation: Foam vs. spray

“…When the fine granules have disappeared, granule induction growth behaviour ceases. This behaviour was also shown by Wauters et al 25 in the granulation of copper concentrate (chalcopyrite) in a rotating drum granulator. The finding implies that the induction period can be shortened by removing the fines, which is similar to the effect of increasing the liquid binder level 1 .…”

“…Wet granule samples were removed from the granulator and immediately frozen using liquid nitrogen 24,25 . The frozen granules were quickly hand sieved into five size fractions using a small stack of sieves (2 mm, 1mm, 500 µm, 250 µm and pan), The moisture content of each size fraction was determined by quickly weighing the wet granule fractions (after the liquid nitrogen had evaporated) and reweighing after drying overnight at 50ºC in a fan-forced oven 24,25 .…”

Modelling nucleation in wet granulation

“…Wauters et al (2002) investigated the spread of binder liquid mass in the spray zone by measuring the mass of binder liquid sprayed with a typical flat fan spray nozzle at different locations underneath the spray. They then projected the collected mass of binder liquid along the direction of powder motion (x-axis in Fig.…”

Granulation rate processes in the kneading elements of a twin screw granulator

“…Binder distribution was quantitatively measured using different analytical techniques in other types of batch granulators and correlated with the span of the granule size distribution. [18][19][20][21][22] However, there is no direct quantitative information available on liquid distribution inside a TSG. Besides size information, other attributes such as the liquid distribution, porosity and the homogeneity of formulation components are essential for mechanistic understanding of a wet granulation process and accurate model development that can be implemented for process scale-up, optimization and control.…”