[en] The knowledge of internal moisture profiles which develop during drying is essential for model validation purposes, but they are difficult to determine experimentally. This paper shows that X-ray microtomography, together with image analysis, provides an accurate, non destructive and easy to use technique to determine moisture profiles. Results reported concern the drying of wastewater sludges whose management is becoming a real environmental challenge. An analysis of the development of moisture gradients at the sample external wall shows an influence of drying operating conditions. Finally, mass diffusion coefficients are estimated from the knowledge of both the moisture gradients and the drying flux.
Disciplines :
Chemical engineering
Author, co-author :
Léonard, Angélique ; Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Opérations physiques unitaires - Département de chimie appliquée
Blacher, Silvia ; Université de Liège - ULiège > Département de Chimique Appliquée > Laboratoire de Génie Chimique
Marchot, Pierre ; Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Systèmes polyphasiques
Pirard, Jean-Paul ; Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Génie catalytique
Crine, Michel ; Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Opérations physiques unitaires
Language :
English
Title :
Moisture profiles determination during convective drying using x-ray microtomography
Alternative titles :
[fr] Détermination des profils d'humidité par microtomographie à rayons X lors du séchage convectif
Publication date :
February 2005
Journal title :
Canadian Journal of Chemical Engineering
ISSN :
0008-4034
Publisher :
Canadian Society for Chemical Engineering, Ottawa, Canada
Volume :
83
Issue :
1
Pages :
127-131
Peer reviewed :
Peer Reviewed verified by ORBi
Funders :
F.R.S.-FNRS - Fonds de la Recherche Scientifique [BE]
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