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Title: In-situ monitoring of calcium carbonate scale progression on reverse osmosis membranes using Raman spectroscopy
Direct monitoring techniques of fouling in membrane-based filtration processes can be implemented as part of an effort to reduce the negative effects of membrane fouling. In particular, monitoring techniques with chemical characterization capability are crucial for the formulation of effective fouling prevention and mitigation strategies. In the present work, Raman spectroscopy was applied as an in-situ monitoring technique for calcium carbonate scaling on commercial reverse osmosis membranes. The bench-scale Raman monitoring system allowed for a qualitative chemical assay of the scaled membrane surface at sequential downstream and upstream axial positions. The time evolution of the downstream and upstream calcium carbonate Raman signal was evaluated with respect to computed values of local concentration at the membrane surface, revealing a statistically significant dependence (p < 0.001). The real-time Raman data were bolstered by results of post-mortem analysis (scanning electron microscopy, gravimetric measurements, and laser interferometry). The employed technique was capable of detecting crystals with characteristic lengths <50 μm. Preliminary evidence of polymorph detection was also presented with recommendations for improvements in the technique.  more » « less
Award ID(s):
1826542
PAR ID:
10477386
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
DESALINATION AND WATER TREATMENT
Date Published:
Journal Name:
DESALINATION AND WATER TREATMENT
Volume:
273
ISSN:
1944-3986
Page Range / eLocation ID:
92 to 103
Subject(s) / Keyword(s):
Calcium carbonate scale progression Raman spectroscopy In-situ monitoring Spatial dependence Reverse osmosis desalination membrane
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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