Show simple item record

dc.contributor.authorPei, Chunleien
dc.contributor.authorElliott, Jamesen
dc.date.accessioned2017-09-07T16:06:16Z
dc.date.available2017-09-07T16:06:16Z
dc.date.issued2017-11-23en
dc.identifier.issn0009-2509
dc.identifier.urihttps://www.repository.cam.ac.uk/handle/1810/267077
dc.description.abstractThe uniformity of the coating thickness distribution is an important quality metric in the manufacture of pharmaceutical tablets during the spray coating process. An investigation of the asymptotic limits of coating thickness variability of tablets of varying shape was carried out based on the cap-to-band coating thickness distributions. A theoretical analysis shows that the cap-to-band coating thickness ratio is expected to be equal to the cap-to-band area ratio projected onto the spray direction divided by the actual cap-to-band surface area ratio. When the cap-to-band projected area ratio is larger (or smaller) than the cap-to-band surface area ratio, the mean coating thickness on the cap is larger (or smaller) than that on the band. To verify this, the dynamics of tablets in a rotating pan was modelled using discrete element method (DEM) simulations, while an image analysis technique based on the output of DEM simulations was applied to model the spray coating process and analyse the cap-to-band coating thickness ratio. A ray-tracing sampling method was further used to obtain the cap-to-band sample ratio. It was also found that a smaller spray angle with respect to the horizontal direction can decrease and even invert the cap-to-band coating thickness ratio, leading to a larger coating thickness on the band than the cap. Nevertheless, an asymptotic value of cap-to-band relative standard deviation can be reached once the cap-to-band coating thickness ratio becomes stable during the coating process. This asymptotic limit is within the range predicted based on the cap-to-band projected area ratio and surface area ratio.
dc.description.sponsorshipUK EPSRC Research Grant EP/L019787/1 and EP/L019922/1
dc.languageengen
dc.publisherElsevier
dc.rightsAttribution-NonCommercial-NoDerivatives 4.0 Internationalen
dc.rightsAttribution-NonCommercial-NoDerivatives 4.0 Internationalen
dc.rightsAttribution-NonCommercial-NoDerivatives 4.0 Internationalen
dc.rights.urihttp://creativecommons.org/licenses/by-nc-nd/4.0/en
dc.rights.urihttp://creativecommons.org/licenses/by-nc-nd/4.0/en
dc.rights.urihttp://creativecommons.org/licenses/by-nc-nd/4.0/en
dc.subjectdiscrete element methoden
dc.subjectspray coating processen
dc.subjectcoating thickness distributionen
dc.subjectcap-to-band ratioen
dc.titleAsymptotic limits on tablet coating variability based on cap-to-band thickness distributions: a discrete element model (DEM) studyen
dc.typeArticle
prism.endingPage296
prism.publicationDate2017en
prism.publicationNameChemical Engineering Scienceen
prism.startingPage286
prism.volume172en
dc.identifier.doi10.17863/CAM.10816
dcterms.dateAccepted2017-06-16en
rioxxterms.versionAMen
rioxxterms.licenseref.urihttp://creativecommons.org/licenses/by-nc-nd/4.0/en
rioxxterms.licenseref.startdate2017-11-23en
dc.contributor.orcidElliott, James [0000-0002-4887-6250]
dc.identifier.eissn1873-4405
rioxxterms.typeJournal Article/Reviewen
pubs.funder-project-idEPSRC (EP/L019922/1)
cam.issuedOnline2017-06-17en
datacite.issupplementedby.doi10.17863/CAM.10704en
rioxxterms.freetoread.startdate2018-06-16


Files in this item

Thumbnail
Thumbnail

This item appears in the following Collection(s)

Show simple item record

Attribution-NonCommercial-NoDerivatives 4.0 International
Except where otherwise noted, this item's licence is described as Attribution-NonCommercial-NoDerivatives 4.0 International