Comparative analysis of granule properties in continuous granulators
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2023Keyword
Hot melt granulationTwin screw melt granulation
Wet granulation
Polyethylene glycol (PEG) 4000
Calcium carbonate (Durcal 65)
Kneading elements (KB)
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© 2023 The Authors. Published by Elsevier B.V. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. (http://creativecommons.org/licenses/by-nc-nd/4.0/).Peer-Reviewed
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Several contributions in answering granulation challenges including the use of computer simulation and well thought out experimental analyses are being researched. Using a twin screw granulator (TSG) by design of experiments (DoE), comparisons on 1) equipment similarities i.e., continuous and 2) shear forces, are made to previous literature on continuous equipment and a Cyclomix. This study proposes that equipment specific DoE, better explains the contribution of parameters than investigating an identified parameter from the experimental findings from a specific equipment. Granule strength and structure are presented together with the contribution of process parameters, speed, temperature, and binder content. Seeded structures are present in all but the Extrudomix. Longer residence times within the Cyclomix facilitates seeded structures. Granule crushing strengths are higher in TSG than all other continuous equipment. Optimum condition for the formation of stronger granules with least variation is around 65.4 °C.Version
Accepted manuscriptCitation
Sekyi N, Kelly A and Rahmanian N (2023) Comparative analysis of granule properties in continuous granulators. Powder Technology. Accepted for Publication.Link to publisher’s version
https://doi.org/10.1016/j.powtec.2023.118557Type
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Effects of process parameters on granules properties produced in a high shear granulatorResults of a study on the influence of process parameters such as impeller speed, granulation time and binder viscosity on granule strength and properties are reported. A high shear granulator (Cyclomix manufactured by Hosokawa Micron B.V., The Netherlands) has been used to produce granules. Calcium carbonate (Durcal) was used as feed powder and aqueous polyethylene glycol (PEG) as the binder. The dried granules have been analysed for their strength, density and size distribution. The results show that increasing the granulation time has a great affect on granules strength, until an optimum time has been reached. The underlying cause is an increase in granule density. Granules are consolidated more at higher impeller speeds. Moreover, the granule size distribution seems not to be affected significantly by an increase in impeller speed. Granules produced with high binder viscosity have a considerably lower strength, wide strength distribution due to poor dispersion of binder on the powder bed. Binder addition methods have showed no considerable effect on granule strength or on granule size distribution.