The following are examples of machines used in large-scale mixing in Wet Granulation EXCEPT:

• A. Patterson Kelley Twin-shell blender
• B. Hobart Planetary Mixer
• C. Glen Planetary Mixer
• D. Reitz Extruder

Answer: (D)

In wet granulation, the key task is to blend powders and evenly distribute moisture and binder on a large scale, so the equipment used is designed for thorough mixing and uniform mass formation. The Patterson Kelly Twin-shell blender accomplishes this by tumbling two shells to blend powders and incorporate binder. The Hobart planetary mixer uses a planetary action that drives the mixing tool and bowl along multiple paths, creating high-shear, uniform wet masses. The Glen planetary mixer operates similarly, providing vigorous mixing and even distribution of moisture and binder in large batches.

The Reitz extruder, by contrast, is not a mixing unit. Its primary function is shaping the material by forcing it through a die to form extrudates or pellets, rather than achieving comprehensive bulk mixing of the powders. So it stands outside the category of large-scale mixing equipment used in wet granulation.