화학공학소재연구정보센터
Powder Technology, Vol.341, 11-22, 2019
A systematic study of the impact of changes of roller compactor equipment on granule and tablet properties
Typical industrial development of roller compaction processes include changes in scale from laboratory to pilot and then further to production scale and also changes in equipment design due to equipment availability in different manufacturing facilities. Transfer and scale-up of roller compaction processes based on conservation of ribbon density is relatively well established, although different equipment designs, such as side seals and ribbon milling systems can lead to changes in downstream quality attributes, including granules and tablets. The aim of this study was to investigate this transfer/scale-up approach by systematically comparing the ribbon, granule and tablet properties between three different roller compactors from the vendors: Hosokawa, Alexanderwerk and Gerteis. A larger amount of uncompacted material was observed for the Hosokawa compared to Alexanderwerk and Gerteis, partly due to side seal leakage. To reduce the material bypass fraction, the Hosokawa was modified by using tight polymer cheek plates and concave rolls although the granules still exhibited a large amount of fines. One cause is the key difference in the roll force control. The roll force on the Hosokawa is controlled by proportional-integral-derivative (PID) regulation of the feeders, which leads to large force variations. In contrast, the Alexanderwerk and Gerteis achieve an almost constant force by using a hydraulic pressure system. Granules from all roller compactors were successfully pressed into tablets, and there was no correlation between the particle size and tabletability. However, the tabletability was better for granules from ribbons with higher porosity, which indicated an effect of granule hardening in the roller compaction step. This work demonstrates that conserving ribbon porosity when moving between different roller compactors is not sufficient to achieve granules with identical properties, indicating that a more advanced approach is needed for scale-up or transfer. (C) 2018 Elsevier B.V. All rights reserved.