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.
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A novel membrane inlet-infrared gas analysis (MI-IRGA) system for monitoring of seawater carbonate system: Carbonate chemistry monitoring with MI-IRGA
- NSF-PAR ID:
- 10022525
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Limnology and Oceanography: Methods
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 1541-5856
- Page Range / eLocation ID:
- 38 to 53
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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