Granulation drying process

Fig. 6.12. Spectra from a granulation drying process. The bound and free water are seen at 1420 and 1440nm, respectively.

FIGURE 6.9 Manufacture of enzyme granules with high shear granulation-drying processes. 

The production process consists of the stages of preparation of the monomer and additive solutions elimination of the dissolved oxygen from the solutions polymerization compounding (i.e., stabilization and granulation) drying, crushing, and packing of the finished product. 

Nevertheless, the acquisition of a sufficiently detailed body of physical information can allow a formulator to go far beyond the mere ability to cope with crises when they develop at unexpected times. For a well-understood system, it is theoretically possible to design an automated or semi-automated manufacturing scheme for which the processing variables would be appropriately controlled so as to minimize the possibility of batch failure. Materials passing the hurdles of physical test specifications would be totally predictable in their performance, and they could therefore be blended, granulated, dried, compressed, and delivered into containers without operator intervention. 

High-energy processes (milling, lyophilisation, granulating, drying) can introduce certain amounts of amorphicity into otherwise highly crystalline material [20]. As has been previously indicated, enhanced levels of amorphicity lead to increased local levels of moismre, and increased chemical reactivity in these areas. Hancock and Zografi [49] reported on the impact of a roller-compaction process on the water vapour sorption of a sample of aspirin. They speculated that... 

The spray-dried flavours or powder blends are processed by a roller compactor into lumps (Fig. 21.12). These lumps are crushed into granules. This process cannot be categorised as a direct encapsulating technique, since the flavour-encapsulating effect of compacted flavours is based on the use of spray-dried raw material. 

A QUASI-CONTINUOUS GRANULATION AND DRYING PROCESS (QCGDP) TO AVOID SCALE-UP PROBLEMS... 

During the granulation or drying process, cloth filters are mechanically shaken to dislodge any product which adhered while cartridge filters use a low pressure compressed air blowback system to do the same. 

Therefore, product temperature should be monitored closely to control the fluidized bed drying process. During fluid-bed drying, the product passes through three distinct temperature phases (Fig. 21). At the beginning of the drying process, the material heats up from the ambient temperature to approximately the wet-bulb temperature of the air in the dryer. This temperature is maintained until the granule moisture content is reduced to the critical level. At this point, the material holds no free surface water, and the temperature starts to rise further. 

In the milling, blending, granulating and or drying processes, the operating principles of the equipment employed should be defined, and the variables determined. The impact and mechanism of measurement on in-process variables should be defined. Time, temperature, work input of equipment, blend/ granulation volume, and granulating rate should be determined. 

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