Evolution and accumulation of organic foulants on hydrophobic and hydrophilic membrane surfaces in a submerged membrane bioreactor
Item Type Conference Paper;Presentation
Authors Matar, Gerald;Gonzalez-Gil, G.;Maab, H.;Nunes, Suzana Pereira;Vrouwenvelder, J.S.;Saikaly, Pascal
Eprint version Publisher's Version/PDF
Journal International Water Association (IWA) Download date 2023-11-29 21:03:22
Link to Item http://hdl.handle.net/10754/581343
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Evolution and Accumulation of Organic Foulants on Hydrophobic and Hydrophilic Membrane Surfaces in a
Submerged Membrane Bioreactor
Gerald Matar, Graciela Gonzalez-Gil, Hans Vrouwenvelder, Suzana Nunes, Pascal Saikaly
Water Desalination and Reuse Center (WDRC)
King Abdullah University of Science and Technology (KAUST)
NOM 6 IWA Specialist Conference on Natural Organic Matter in Water
September 10, 2015
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• Study the dynamics and evolution of organic foulants and the EPS products from microbial communities, in a lab-
scale MBR operated with five membranes having different hydrophobic or hydrophilic properties
• Does membrane surface chemistry select for specific
foulants?
• Nitrification/denitrification
(intermittent aeration: 30 min ON/
30 min OFF cycles)
• SRT of 15 days and HRT of 12 hours
• MLVSS: 3.12 g/L
• Parallel modules: flux (10 LMH)
vs. no flux (static mode)
6
Sampling days
1
10
20
30
Flux EPS fingerprint
In fouled membrane Architecture
of biofilm
SEM and CLSM imaging Biomass & EPS staining (2 fibers) EPS extraction
(2 fibers)
Fingerprint of EPS samples:
LC-OCD 3D-EEM Fingerprint Proteins &
Exopolysaccharides FT-IR
Tested Membranes
Duplicate MLSS sample were collected in parallel to each membrane sampling event
Hydrophilic:
SPTA SPSF COM
No flux and 10 LMH
Hydrophobic:
POX PTA
Membrane characterization conducted at each sampling event
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Membrane type
Acronym Nominal pore size (µm)
Contact Angle (o)
Zeta
potential (mV)
Polymer composition and characteristics
Polyoxadiazole POX 0.1 96.5±3 -28.1±1 Very hydrophobic
membrane (fluorinated)
Polytriazole PTA 0.1 85±12 -30.8±1 Hydrophobic membrane (fluorinated)
Sulfonated Polytriazole
SPTA 0.1 65.5±7 -23±1 Hydrophilic membrane (sulfonic group)
Sulfonated Polysulfone
SPSF 0.1 54.5±4 -106±1 Hydrophilic membrane (sulfonic group)
Commercial Membrane
COM 0.1 n.a. n.a. Commercial membrane (PVDF)
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Amide&I&
(1640)&
Amide&II&
(1560)& Amide&III&
(1414)&
Humics,&Lipids,&
proteins&(1730)&
Threonine&
(1339)&
Aminosugars&
(1384)&
SPSF$
SPTA$
PTA$
POX$
COM$
Aminosugars&
(1384)&
Pectin&
(1022)&
Sugars&
(1070)&
Cellulose&
(1124)&
CarboHacids&
COOH&(880)&
Carbohydrates&
(806)&
SiO&&
(469)&
Day$1$ OHH&stretch&
(3435)&
NHH;&AmideHA&
(3294)&
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11
12
13
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Despite differences in TMP, the membrane surface characteristics did not affect the composition of the organic foulants, and the EPS products evolved similarly with time (flux and no flux)•
The same EPS dynamics was observed on the surfaces of all themembranes tested, where initially (day 1) proteins were more abundant than polysaccharides and at the end of the experiment (day 30)
polysaccharides were more abundant
•
The combination of analytical tools provided a coherent andcomprehensive analysis of the accumulated fouling components on the membranes
•
Membrane surface chemistry might play a role in selecting the conditioning fouling layer during the initial stages of filtration, but become irrelevant following longer stages of membrane operation• Graciela Gonzalez-Gil, Hans Vrouwenvelder, Suzana Nunes:
King Abdullah University of Sciences and Technology, Saudi Arabia
• Pascal E. Saikaly: PI - King Abdullah University of Sciences and Technology, Saudi Arabia
• Funding: King Abdullah University of Sciences and Technology (KAUST)
