Compaction and relaxation of biofilms

Handle URI:
http://hdl.handle.net/10754/594186
Title:
Compaction and relaxation of biofilms
Authors:
Valladares Linares, R.; Wexler, A. D.; Bucs, Szilard; Dreszer, C.; Zwijnenburg, A.; Flemming, H. C.; Kruithof, J. C.; Vrouwenvelder, Johannes S. ( 0000-0003-2668-2057 )
Abstract:
Operation of membrane systems for water treatment can be seriously hampered by biofouling. A better characterization of biofilms in membrane systems and their impact on membrane performance may help to develop effective biofouling control strategies. The objective of this study was to determine the occurrence, extent and timescale of biofilm compaction and relaxation (decompaction), caused by permeate flux variations. The impact of permeate flux changes on biofilm thickness, structure and stiffness was investigated in situ and non-destructively with optical coherence tomography using membrane fouling monitors operated at a constant crossflow velocity of 0.1 m s−1 with permeate production. The permeate flux was varied sequentially from 20 to 60 and back to 20 L m−2 h−1. The study showed that the average biofilm thickness on the membrane decreased after elevating the permeate flux from 20 to 60 L m−2 h−1 while the biofilm thickness increased again after restoring the original flux of 20 L m−2 h−1, indicating the occurrence of biofilm compaction and relaxation. Within a few seconds after the flux change, the biofilm thickness was changed and stabilized, biofilm compaction occurred faster than the relaxation after restoring the original permeate flux. The initial biofilm parameters were not fully reinstated: the biofilm thickness was reduced by 21%, biofilm stiffness had increased and the hydraulic biofilm resistance was elevated by 16%. Biofilm thickness was related to the hydraulic biofilm resistance. Membrane performance losses are related to the biofilm thickness, density and morphology, which are influenced by (variations in) hydraulic conditions. A (temporarily) permeate flux increase caused biofilm compaction, together with membrane performance losses. The impact of biofilms on membrane performance can be influenced (increased and reduced) by operational parameters. The article shows that a (temporary) pressure increase leads to more compact biofilms with a higher hydraulic resistance. © 2015 Balaban Desalination Publications. All rights reserved.
KAUST Department:
Biological and Environmental Sciences and Engineering (BESE) Division; Water Desalination and Reuse Research Center (WDRC)
Citation:
Valladares Linares R, Wexler AD, Bucs SS, Dreszer C, Zwijnenburg A, et al. (2015) Compaction and relaxation of biofilms. Desalination and Water Treatment: 1–13. Available: http://dx.doi.org/10.1080/19443994.2015.1057036.
Publisher:
Informa UK Limited
Journal:
Desalination and Water Treatment
Issue Date:
18-Jun-2015
DOI:
10.1080/19443994.2015.1057036
Type:
Article
ISSN:
1944-3994; 1944-3986
Appears in Collections:
Articles; Water Desalination and Reuse Research Center (WDRC); Biological and Environmental Sciences and Engineering (BESE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorValladares Linares, R.en
dc.contributor.authorWexler, A. D.en
dc.contributor.authorBucs, Szilarden
dc.contributor.authorDreszer, C.en
dc.contributor.authorZwijnenburg, A.en
dc.contributor.authorFlemming, H. C.en
dc.contributor.authorKruithof, J. C.en
dc.contributor.authorVrouwenvelder, Johannes S.en
dc.date.accessioned2016-01-19T13:23:24Zen
dc.date.available2016-01-19T13:23:24Zen
dc.date.issued2015-06-18en
dc.identifier.citationValladares Linares R, Wexler AD, Bucs SS, Dreszer C, Zwijnenburg A, et al. (2015) Compaction and relaxation of biofilms. Desalination and Water Treatment: 1–13. Available: http://dx.doi.org/10.1080/19443994.2015.1057036.en
dc.identifier.issn1944-3994en
dc.identifier.issn1944-3986en
dc.identifier.doi10.1080/19443994.2015.1057036en
dc.identifier.urihttp://hdl.handle.net/10754/594186en
dc.description.abstractOperation of membrane systems for water treatment can be seriously hampered by biofouling. A better characterization of biofilms in membrane systems and their impact on membrane performance may help to develop effective biofouling control strategies. The objective of this study was to determine the occurrence, extent and timescale of biofilm compaction and relaxation (decompaction), caused by permeate flux variations. The impact of permeate flux changes on biofilm thickness, structure and stiffness was investigated in situ and non-destructively with optical coherence tomography using membrane fouling monitors operated at a constant crossflow velocity of 0.1 m s−1 with permeate production. The permeate flux was varied sequentially from 20 to 60 and back to 20 L m−2 h−1. The study showed that the average biofilm thickness on the membrane decreased after elevating the permeate flux from 20 to 60 L m−2 h−1 while the biofilm thickness increased again after restoring the original flux of 20 L m−2 h−1, indicating the occurrence of biofilm compaction and relaxation. Within a few seconds after the flux change, the biofilm thickness was changed and stabilized, biofilm compaction occurred faster than the relaxation after restoring the original permeate flux. The initial biofilm parameters were not fully reinstated: the biofilm thickness was reduced by 21%, biofilm stiffness had increased and the hydraulic biofilm resistance was elevated by 16%. Biofilm thickness was related to the hydraulic biofilm resistance. Membrane performance losses are related to the biofilm thickness, density and morphology, which are influenced by (variations in) hydraulic conditions. A (temporarily) permeate flux increase caused biofilm compaction, together with membrane performance losses. The impact of biofilms on membrane performance can be influenced (increased and reduced) by operational parameters. The article shows that a (temporary) pressure increase leads to more compact biofilms with a higher hydraulic resistance. © 2015 Balaban Desalination Publications. All rights reserved.en
dc.publisherInforma UK Limiteden
dc.subjectBiofilm thicknessen
dc.subjectBiofoulingen
dc.subjectCompressibilityen
dc.subjectCompressionen
dc.subjectConsolidationen
dc.subjectHydraulic biofilm resistanceen
dc.subjectMembrane filtration systemen
dc.subjectOptical coherence tomographyen
dc.titleCompaction and relaxation of biofilmsen
dc.typeArticleen
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
dc.contributor.departmentWater Desalination and Reuse Research Center (WDRC)en
dc.identifier.journalDesalination and Water Treatmenten
dc.contributor.institutionWetsus, European Centre of Excellence of Sustainable Water Technology, Oostergoweg 9, 8911 MA Leeuwarden, The Netherlandsen
dc.contributor.institutionBiofilm Centre, University Duisburg-Essen, Universitätsstrasse 5, 45141 Essen, Germanyen
dc.contributor.institutionFaculty of Applied Sciences, Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlandsen
kaust.authorValladares Linares, Rodrigoen
kaust.authorBucs, Szilarden
kaust.authorVrouwenvelder, Johannes S.en
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