title: A new way to apply ultrasound in cross-flow ultrafiltration: application to colloidal suspensions.
abstract: A new coupling of ultrasound device with membrane process has been developed in order to enhance cross-flow ultrafiltration of colloidal suspensions usually involved in several industrial applications included bio and agro industries, water and sludge treatment. In order to reduce mass transfer resistances induced by fouling and concentration polarization, which both are main limitations in membrane separation process continuous ultrasound is applied with the help of a vibrating blade (20 kHz) located in the feed channel all over the membrane surface (8mm between membrane surface and the blade). Hydrodynamic aspects were also taking into account by the control of the rectangular geometry of the feed channel. Three colloidal suspensions with different kinds of colloidal interaction (attractive, repulsive) were chosen to evaluate the effect of their physico-chemical properties on the filtration. For a 90 W power (20.5 W cm(-2)) and a continuous flow rate, permeation fluxes are increased for each studied colloidal suspension, without damaging the membrane. The results show that the flux increase depends on the initial structural properties of filtered dispersion in terms of colloidal interaction and spatial organizations. For instance, a Montmorillonite Wyoming-Na clay suspension was filtered at 1.5 × 10(5)Pa transmembrane pressure. Its permeation flux is increased by a factor 7.1, from 13.6 L m(-2)h(-1) without ultrasound to 97 L m(-2)h(-1) with ultrasound.
authors.affiliation: Laboratoire Rhéologie et Procédés, Université Joseph Fourier Grenoble I, Grenoble-INP, CNRS, UMR 5520, BP 53, 38041 Grenoble Cedex 9, France. Electronic address: hengl@ujf-grenoble.fr.
authors.forename: N
authors.initials: N
authors.lastname: Hengl
authors.affiliation: Laboratoire Rhéologie et Procédés, Université Joseph Fourier Grenoble I, Grenoble-INP, CNRS, UMR 5520, BP 53, 38041 Grenoble Cedex 9, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Jin
authors.affiliation: Laboratoire Rhéologie et Procédés, Université Joseph Fourier Grenoble I, Grenoble-INP, CNRS, UMR 5520, BP 53, 38041 Grenoble Cedex 9, France.
authors.forename: F
authors.initials: F
authors.lastname: Pignon
authors.affiliation: Laboratoire Rhéologie et Procédés, Université Joseph Fourier Grenoble I, Grenoble-INP, CNRS, UMR 5520, BP 53, 38041 Grenoble Cedex 9, France.
authors.forename: S
authors.initials: S
authors.lastname: Baup
authors.affiliation: Laboratoire Rhéologie et Procédés, Université Joseph Fourier Grenoble I, Grenoble-INP, CNRS, UMR 5520, BP 53, 38041 Grenoble Cedex 9, France.
authors.forename: R
authors.initials: R
authors.lastname: Mollard
authors.affiliation: Laboratoire Rhéologie et Procédés, Université Joseph Fourier Grenoble I, Grenoble-INP, CNRS, UMR 5520, BP 53, 38041 Grenoble Cedex 9, France.
authors.forename: N
authors.initials: N
authors.lastname: Gondrexon
authors.affiliation: Laboratoire Rhéologie et Procédés, Université Joseph Fourier Grenoble I, Grenoble-INP, CNRS, UMR 5520, BP 53, 38041 Grenoble Cedex 9, France.
authors.forename: A
authors.initials: A
authors.lastname: Magnin
authors.affiliation: Laboratoire Environnement et Minéralurgie, CNRS-Université de Lorraine UMR 7569, 15 Avenue du Charmois, BP 40, 54501 Vandœuvre Cedex, France.
authors.forename: L
authors.initials: L
authors.lastname: Michot
authors.affiliation: Laboratoire de Physique des Solides, CNRS-Université Paris XI UMR 8502, Bat. 510, 91405 Orsay Cedex, France.
authors.forename: E
authors.initials: E
authors.lastname: Paineau
mesh_terms: D008567:Membranes, Artificial; D011108:Polymers / Q000737:chemistry; D017640:Silicates / Q000737:chemistry; D013450:Sulfones / Q000737:chemistry; D013535:Suspensions / Q000737:chemistry*; D014462:Ultrafiltration / Q000379:methods*; D014465:Ultrasonics / Q000379:methods*
chemical_list: D008567:Membranes, Artificial; D011108:Polymers; D017640:Silicates; D013450:Sulfones; D013535:Suspensions; C022840:polyether sulfone; C524813:laponite
keywords: Concentration polarization; Fouling; Process enhancement; Ultrafiltration; Ultrasound