Handle URI:
http://hdl.handle.net/10754/334482
Title:
Ceramic Ultrafiltration of Marine Algal Solutions: A Comprehensive Study
Authors:
Dramas, Laure ( 0000-0002-8883-2084 )
Abstract:
Algal bloom can significantly impact reverse osmosis desalination process and reduce the drinking water production. In 2008, a major bloom event forced several UAE reverse osmosis plants to stop their production, and in this context, a better understanding of UF membrane fouling caused by algal organic matter (AOM) is needed, in order to adjust the filtration conditions during algal bloom events. Polymeric MF/UF membranes are already widely used for RO pretreatment, but ceramic UF membranes can also be an alternative for the filtration of marine algal solutions. The fouling potential of the Red Sea and the Arabian Sea, sampled at different seasons, along with four algal monocultures grown in laboratory, and one mesocosm experiment in the Red Sea was investigated. Algal solutions induce a stronger and more irreversible fouling than terrestrial humic solution, toward ceramic membrane. During algal bloom events, this fouling is enhanced and becomes even more problematic at the decline phase of the bloom, for a similar initial DOC. Three main mechanisms are involved: the formation of a cake layer at the membrane surface; the penetration of the algal organic matter (AOM) in the pore network of the membrane; the strong adhesion of AOM with the membrane surface. The last mechanism is species-specific and metal-oxide specific. In order to understand the stronger ceramic UF fouling at the decline phase, AOM quality was analyzed every two days. During growth, AOM is getting enriched in High Molecular Weight (HMW) structures (> 200 kDa), which are mainly composed by proteins and polysaccharides, and these compounds seem to be responsible for the stronger fouling at decline phase. In order to prevent the fouling of ceramic membrane, coagulation-flocculation (CF) using ferric chloride was implemented prior to filtration. It permits a high removal of HMW compounds and greatly reduces the fouling potential of the algal solution. During brief algal bloom events, CF should be implemented prior to UF to protect the membranes. A comparison between polymeric and ceramic UF membranes showed that ceramic membrane suffers from a stronger fouling but permits a better removal of DOC and particularly HMW compounds.
Advisors:
Croue, Jean-Philippe
Committee Member:
Irigoien, Xabier ( 0000-0002-5411-6741 ) ; Teychene, Benoit; Leiknes, Torove
KAUST Department:
Biological and Environmental Sciences and Engineering (BESE) Division
Program:
Environmental Science and Engineering
Issue Date:
Sep-2014
Type:
Dissertation
Appears in Collections:
Environmental Science and Engineering Program; Dissertations; Biological and Environmental Sciences and Engineering (BESE) Division

Full metadata record

DC FieldValue Language
dc.contributor.advisorCroue, Jean-Philippeen
dc.contributor.authorDramas, Laureen
dc.date.accessioned2014-11-11T13:54:02Z-
dc.date.available2014-11-11T13:54:02Z-
dc.date.issued2014-09en
dc.identifier.urihttp://hdl.handle.net/10754/334482en
dc.description.abstractAlgal bloom can significantly impact reverse osmosis desalination process and reduce the drinking water production. In 2008, a major bloom event forced several UAE reverse osmosis plants to stop their production, and in this context, a better understanding of UF membrane fouling caused by algal organic matter (AOM) is needed, in order to adjust the filtration conditions during algal bloom events. Polymeric MF/UF membranes are already widely used for RO pretreatment, but ceramic UF membranes can also be an alternative for the filtration of marine algal solutions. The fouling potential of the Red Sea and the Arabian Sea, sampled at different seasons, along with four algal monocultures grown in laboratory, and one mesocosm experiment in the Red Sea was investigated. Algal solutions induce a stronger and more irreversible fouling than terrestrial humic solution, toward ceramic membrane. During algal bloom events, this fouling is enhanced and becomes even more problematic at the decline phase of the bloom, for a similar initial DOC. Three main mechanisms are involved: the formation of a cake layer at the membrane surface; the penetration of the algal organic matter (AOM) in the pore network of the membrane; the strong adhesion of AOM with the membrane surface. The last mechanism is species-specific and metal-oxide specific. In order to understand the stronger ceramic UF fouling at the decline phase, AOM quality was analyzed every two days. During growth, AOM is getting enriched in High Molecular Weight (HMW) structures (> 200 kDa), which are mainly composed by proteins and polysaccharides, and these compounds seem to be responsible for the stronger fouling at decline phase. In order to prevent the fouling of ceramic membrane, coagulation-flocculation (CF) using ferric chloride was implemented prior to filtration. It permits a high removal of HMW compounds and greatly reduces the fouling potential of the algal solution. During brief algal bloom events, CF should be implemented prior to UF to protect the membranes. A comparison between polymeric and ceramic UF membranes showed that ceramic membrane suffers from a stronger fouling but permits a better removal of DOC and particularly HMW compounds.en
dc.language.isoenen
dc.subjectUltrafilitrationen
dc.subjectceramic membraneen
dc.subjectAlgal bloomen
dc.subjectFoulingen
dc.subjectalgal organic matteren
dc.subjectCharacterizationen
dc.titleCeramic Ultrafiltration of Marine Algal Solutions: A Comprehensive Studyen
dc.typeDissertationen
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
thesis.degree.grantorKing Abdullah University of Science and Technologyen_GB
dc.contributor.committeememberIrigoien, Xabieren
dc.contributor.committeememberTeychene, Benoiten
dc.contributor.committeememberLeiknes, Toroveen
thesis.degree.disciplineEnvironmental Science and Engineeringen
thesis.degree.nameDoctor of Philosophyen
dc.person.id107805en
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