Watson, NJ, Povey, MJW, Reynolds, GK et al. (2 more authors) (2014) Acoustic emission monitoring from a lab scale high shear granulator - A novel approach. International Journal of Pharmaceutics, 465 (1-2). pp. 262-274. ISSN 0378-5173
Abstract
A new approach to the monitoring of granulation processes using passive acoustics together with precise control over the granulation process has highlighted the importance of particle-particle and particle-bowl collisions in acoustic emission. The results have shown that repeatable acoustic results could be obtained but only when a spray nozzle water addition system was used. Acoustic emissions were recorded from a transducer attached to the bowl and an airborne transducer. It was found that the airborne transducer detected very little from the granulation and only experienced small changes throughout the process. The results from the bowl transducer showed that during granulation the frequency content of the acoustic emission shifted towards the lower frequencies. Results from the discrete element model indicate that when larger particles are used the number of collisions the particles experience reduces. This is a result of the volume conservation methodology used in this study, therefore larger particles results in less particles. These simulation results coupled with previous theoretical work on the frequency content of an impacting sphere explain why the frequency content of the acoustic emissions reduces during granule growth. The acoustic system used was also clearly able to identify when large over-wetted granules were present in the system, highlighting its benefit for detecting undesirable operational conditions. High-speed photography was used to study if visual changes in the granule properties could be linked with the changing acoustic emissions. The high speed photography was only possible towards the latter stages of the granulation process and it was found that larger granules produced a higher magnitude of acoustic emission across a broader frequency range.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | (c) 2014 Elsevier B.V. This is an author produced version of a paper published in International Journal of Pharmaceutics. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | Granulation; High shear mixer; Process monitoring; Passive acoustic monitoring; High speed photography; Discrete element monitoring |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemical & Process Engineering (Leeds) > Institute for Particle Science and Engineering (Leeds) The University of Leeds > Faculty of Environment (Leeds) > School of Food Science and Nutrition (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 01 Apr 2016 13:55 |
Last Modified: | 27 Jan 2018 03:06 |
Published Version: | http://dx.doi.org/10.1016/j.ijpharm.2014.01.032 |
Status: | Published |
Publisher: | Elsevier |
Identification Number: | 10.1016/j.ijpharm.2014.01.032 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:89611 |