General Considerations on Wet Granulation

Wet granulators can be divided into three main types low-shear granulators, high-shear granulators, and fluidized bed granulators.1-4,6 The third type is the focus of another chapter in this book and will not be discussed in details here. Table 5.1 provides a summary of some of the different granulators that are commonly used in the pharmaceutical industry. 

Low-Shear Granulators. These are the traditional granulators and are of the planetary type (e.g., Hobart, Collette) or the kneading type (Z-blade mixers). Another type of these low-shear granulators consists of a V-blender with an intensifier bar (e.g., Patterson-Kelley). 

TABLE 5.1 Summary of Some Wet Granulation Equipment Commonly Used in the Pharmaceutical Industry 

High-shear wet Horizontal (side driven) Lodige 

Raw materials used in wet granulations have different purposes and can be placed in different functional classes.1 1 These materials may be part of the granules themselves (i.e., intragranular) or may be added externally to the granules (i.e., extragranular). 

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