No full text
Paper published in a journal (Scientific congresses, symposiums and conference proceedings)
The fluid mechanics of membrane filtration
HALE, Jack; Harris, A.; Li, Q. et al.
2008In ASME International Mechanical Engineering Congress and Exposition, Proceedings, 8 PART A, p. 63-67
 

Files


Full Text
No document available.

Send to



Details



Keywords :
Crossflow filtration; Membrane filtration; Colloids; Macromolecules; Membranes; Nanofiltration; Viruses; Fluid mechanics
Abstract :
[en] Reverse osmosis and nanofiltration membranes remove colloids, macromolecules, salts, bacteria and even some viruses from water. In crossflow filtration, contaminated water is driven parallel to the membrane, and clean permeate passes through. A large pressure gradient exists across the membrane, with permeate flow rates two to three orders of magnitude smaller than that of the crossflow. Membrane filtration is hindered by two mechanisms, concentration polarization and caking. During filtration, the concentration of rejected particles increases near the membrane surface, forming a concentration polarization layer. Both diffusive and convective transport drive particles back into the bulk flow. However, the increase of the apparent viscosity in the concentration polarization layer hinders diffusion of particles back into the bulk and results in a small reduction in permeate flux. Depending on the number and type of particles present in the contaminated water, the concentration polarization will either reach a quasi-steady state or particles will begin to deposit onto the membrane. In the later case, a cake layer eventually forms on the membrane, significantly reducing the permeate flux. Contradictive theories suggest that the cake layer is either a porous solid or a very viscous (yield stress) fluid. New and refined models that shed light on these theories are presented. Copyright © 2007 by ASME.
Disciplines :
Mechanical engineering
Author, co-author :
HALE, Jack  ;  Bristol University > Department of Mechanical Engineering
Harris, A.;  Rice University, Department of Civil and Environmental Engineering, MS-318, 6100 Main Street, Houston, TX 77005, United States
Li, Q.;  Rice University, Department of Civil and Environmental Engineering, MS-318, 6100 Main Street, Houston, TX 77005, United States
Houchens, B. C.;  Rice University, Department of Mechanical Engineering and Materials Science, MS-321, 6100 Main Street, Houston, TX 77005, United States
Language :
English
Title :
The fluid mechanics of membrane filtration
Publication date :
2008
Event name :
ASME International Mechanical Engineering Congress and Exposition, IMECE 2007
Event date :
11 November 2007 through 15 November 2007
Journal title :
ASME International Mechanical Engineering Congress and Exposition, Proceedings
Volume :
8 PART A
Pages :
63-67
Focus Area :
Computational Sciences
Commentary :
72091 0791843025; 9780791843024
Available on ORBilu :
since 07 November 2013

Statistics


Number of views
100 (0 by Unilu)
Number of downloads
0 (0 by Unilu)

Scopus citations®
 
1
Scopus citations®
without self-citations
1
WoS citations
 
0

Bibliography


Similar publications



Contact ORBilu