[en] Secondary sludges from two different wastewater treatment plants are conditioned and dewatered in the same way before drying in a lab-scale convective rig at the same operating conditions. Several techniques are used to characterize the texture of the dried materials over a wide range of scales from nm up to mm. Texture and porosity of the dried products are studied by SEM imaging, nitrogen absorption isotherms (0.5 < d(p) < 50 nm), mercury porosimetry (7.5 nm < d(p) < 150 mum) and X-ray microtomography (spatial resolution= 41 mum). The image analysis of cross-sections reconstructed by microtomography also allows following shrinkage and textural evolution during drying.
Disciplines :
Chemical engineering Mechanical 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 chimie appliquée > Labo de génie chimique
Pirard, René ; Université de Liège - ULiège > Département de chimie appliquée > Génie chimique - Génie catalytique
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 :
Multiscale texture characterization of wastewater sludges dried in a convective rig
Alternative titles :
[fr] Caractérisation multi-échelle de la texture de boues séchées par une méthode convective
Publication date :
2003
Journal title :
Drying Technology
ISSN :
0737-3937
eISSN :
1532-2300
Publisher :
Marcel Dekker Inc, New York, United States - New York
Volume :
21
Issue :
8
Pages :
1507-1526
Peer reviewed :
Peer Reviewed verified by ORBi
Funders :
F.R.S.-FNRS - Fonds de la Recherche Scientifique [BE]
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