Setup for granulating and drying tabletted preparations

Conclusions

• 1. In the given setup the drying process is very intensive and ensures a moisture removal rate of 70 kg/m² · h in the case of norsulfazole and 50kg/m² · h in the case of pyramidon.

• 2. Compared with tray-type driers the duration of the process is reduced by a factor of 100 or more (2–3 min instead of 5–10 h).

• 3. The optimum process variables for the preparations studied have been found. Thus, in the case of pyramidon the air temperature should be 90° and its mass flow rate 0.7–0.5 kg/m²· h, and in the case of norsulfazone the air temperature should be 140° and the mass flow rate 0.8 kg/m² · h. The corresponding height of the stationary layer of material should be 40–50 mm.

• 4. In the case of pyramidon drying should be continued to an equilibrium moisture content of 0.4%, and in the case of norsulfazone to a moisture content of 1.5–1.0%. If these levels are adhered to the tablets produced scarcely ever undergo compaction during storage.

  In this drying setup product carry-over is insignificant.