Impact of Feed Spacer Filament Spacing on Mass Transport and Fouling Propensities of RO Membrane Surfaces
MetadataShow full item record
Material build-up on membrane surfaces is one of the vital challenges faced by Reverse Osmosis (RO) operations leading to many operational and maintenance issues. To date, several modelling studies dealt with flow behaviour and concentration patterns for crossflow membrane operations. However, the relative fouling propensities of top and bottom membrane surfaces are never addressed in any study for narrow channels filled with ladder type spacers. In the present work, fluid flow patterns through different spacer configurations are visualized using ANSYS FLUENT by varying the dimensionless filament spacing, L (ratio of top or bottom filament spacing and channel height). Results clearly indicated that average shear stress values for the top membrane surface are always higher (3 to 8 times) than bottom membrane surface but yielded approximately similaraverage values of mass transfer coefficient for the two walls, for low to moderate filament spacings of L≤3 (SP22, and SP33) indicating similar fouling propensities of membrane surfaces. Further increase in filament spacing with L≥4 (SP44 and SP66), the average mass transfer coefficient for the top membrane indicated a sharp decline suggesting increased fouling propensity compared to bottom membrane which is not a desirable feature. Among the four spacer arrangements studied, SP44 (with L=4) was found to be the optimal arrangement yielding moderate pressure drop with nearly equal/higher area weighted values of mass transfer coefficient for the two walls and would lead to lower and equal fouling tendencies for top and bottom membrane surfaces respectively.
This is an Author's Accepted Manuscript of an article published in the Chemical Engineering Communications (2014), copyright Taylor & Francis, available online at: <a href="http://www.tandfonline.com/10.1080/00986445.2013.860525">http://www.tandfonline.com/10.1080/00986445.2013.860525</a>
Showing items related by title, author, creator and subject.
Saeed, Asim (2012)Among different types of membrane modules used for cross flow filtration processes, Spiral Wound Module (SWM) dominates in the area of Ultra Filtration (UF), Nano Filtration (NF) and RO (Reverse Osmosis) due to high packing ...
Investigations into the effects of mass transport and flow dynamics of spacer filled membrane modules using CFDSaeed, Asim; Vuthaluru, Rupa; Vuthaluru, Hari (2014)Cross-flow membrane operations often experience material build-up on membrane surfaces leading to maintenance issues. Although several studies addressed the flow distributions and concentration patterns during membrane ...
Concept of spacer configuration efficay (SCE) applied to optimize ladder type feed spacer filament spacing in narrow channelsSaeed, Asim; Vuthaluru, Rupa; Vuthaluru, Hari (2013)Cross-flow membrane operations are often confronted with the challenges associated with the periodic build-up of material on the membrane surfaces and lead to many operational and maintenance issues. The traditional ...