Clinical Autopsy of a Reverse Osmosis Membrane Module

Graciela Gonzalez-Gil*, Ali Reza Behzad, Andreia S.F. Farinha, Chengyan Zhao, Szilard S. Bucs, Tariq Nada, Ratul Das, Thomas Altmann, Paulus J. Buijs, Johannes S. Vrouwenvelder*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

14 Scopus citations

Abstract

The desalination of seawater using reverse osmosis membranes is an attractive solution to global freshwater scarcity. However, membrane performance is reduced by (bio)fouling. Membrane autopsies are essential for identifying the type of fouling material, and applying corrective measures to minimize membrane fouling. Information from full-scale membrane autopsies guiding improved plant operations is scant in the formal literature. In this case-study, a reverse osmosis membrane from a full-scale seawater desalination plant with a feed channel pressure drop increase of about 218% over the pressure vessel was autopsied. The simultaneous determination of microbial cells, ATP, and total organic carbon (TOC) abundances per membrane area allowed estimating the contributions of biofouling and organic fouling. The abundance of microbial cells determined by flow cytometry (up to 7 × 108 cells/cm2), and ATP (up to 21,000 pg/cm2) as well as TOC (up to 98 μg/cm2) were homogeneously distributed on the membrane. Inorganic fouling was also measured, and followed a similar coverage distribution to that of biofouling. Iron (∼150 μg/cm2, estimated by ICP-MS) was the main inorganic foulant. ATR-FTIR spectra supported that membrane fouling was both organic/biological and inorganic. High-resolution SEM-EDS imaging of cross-sectioned membranes allowed assessing the thickness of the fouling layer (up to 20 μm) and its elemental composition. Imaging results further supported the results of homogeneous fouling coverage. Moreover, imaging revealed both zones with and without compression of the polysulfone membrane layer, suggesting that the stress due to operating pressure was heterogeneous. The procedure for this membrane autopsy provided a reasonable overview of the diverse contributors of fouling and might be a starting point to building a consensus autopsy protocol. Next, it would be valuable to build a RO membrane autopsy database, which can be used as a guidance and diagnostic tool to improve the management and operation of RO desalination plants.

Original languageEnglish (US)
Article number683379
JournalFrontiers in Chemical Engineering
Volume3
DOIs
StatePublished - 2021

Keywords

  • biofouling
  • drinking water
  • fouling
  • full scale desalination plant
  • membrane compression
  • membrane module autopsy
  • reverse osmosis

ASJC Scopus subject areas

  • Catalysis
  • Bioengineering
  • Chemical Engineering (miscellaneous)

Fingerprint

Dive into the research topics of 'Clinical Autopsy of a Reverse Osmosis Membrane Module'. Together they form a unique fingerprint.

Cite this