Granulation liquid drop size

As outlined previously, wetting is the first stage in wet granulation involving liquid binder distribution to the feed powder. There are two extremes (1) liquid drop size is large compared to unit or primary particle size of the feed and (2) particle size is large compared to the drop size. 

Near-elastic granules Here, the wetted granule is considered as a nearly elastic sphere with a liquid layer on the surface. This is a good model for cases where the drop size is much smaller than the granule size and the granulator has simultaneous drying. This model is often suitable for fluid-bed granulation. 

The granulate-filled sandwich structure described in Section II.B permits continuously operated loop systems to be developed as replacements for batch processes. Loop reactors so equipped also exhibit advantages by comparison to conventional fixed-bed reactors better exploitation of the catalytically active component due to smaller granulate size, lower pressure drop, and better gas-liquid mass transfer. 

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