Granulators batch planetary

Batch planetary mixers are used extensively in the pharmaceutical industiy for powder granulation. A typical batch size of 100 to 200 kg has a power input of 10 to 20 kW. Mixing times in these granulators are quite long (20 to 40 min). 

A third batch was prepared with formula 6, using a planetary mixer for the granulation. It was dried in a ventilated oven. 

In the standard wet granulating method used to produce tablet feed in the pharmaceutical industry, sigma blade or heavy duty planetary mixers are often employed [12]. These machines may handle 220 or 440 lb (100 or 200 kg) batches and employ 7 to 10 hp (5.2 to 7.5 kW) drives to knead and... 

Experiments with five different planetary mixers with batch sizes ranging from 3.75 kg to 60 kg showed that, if the binder is mixed in as a dry powder and then liquid is added at a constant rate proportional to the batch size, the ratio of the granulation liquid quantity to a batch size is constant. This was shown for non-viscous binders. 

The ratio of quantity of granulating liquid to batch size at the inflection point of power vs. time curve is constant irrespective of batch size and type of machine. Moreover, for a constant rate of low viscosity binder addition proportional to the batch size, the rate of change (slope or time derivative) of torque or power consumption curve is linearly related to the batch size for a wide spectrum of high shear and planetary mixers. In other words, the process end-point, as determined in a certain region of the curve, is a practically proven scale-up parameter for moving the product from laboratory to production mixers of different sizes and manufacturers. 

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