Membrane Technology for Water Treatment, Desalination and Separations

Membrane Technology for Water Treatment, Desalination and Separations

  1. Membrane Technology for Water Treatment, Desalination and Separations

Membrane-based processes (Reverse Osmosis – RO, Nanofiltration – NF, Ultrafiltration – UF, Microfiltration – MF) are already established as the dominant technology for brackish and sea-water desalination, potable water purification, and treatment of effluents of various types for clean water recovery. Moreover, such membrane processes tend to displace many other conventional separation operations in the process and related industries. NRRE has developed expertise in membrane technology, by performing research in a broad range of topics covering all major aspects of membrane process design and operation. This research includes in-depth studies of membrane module design, of the major operating problems of membrane fouling and scaling, and of membrane system simulation and optimization.

The development of innovative methods has been successfully pursued for on-line monitoring of desalination membrane performance, plant-wide, based on permeate water quality. R&D studies on the important Membrane Bio-Reactor (MBR) technology are carried out, using innovative diagnostic tools, for improved operation and applications to effluents heavily loaded with compounds difficult to biodegrade. Research is also carried out on novel membrane-based methods (including membrane distillation, membrane extraction, pressure retarded osmosis, forward osmosis).

1.1  Membrane Equipment and Process Design / Optimization         

Membrane Module – Design and Performance Optimization  

  • Spacers in Spiral-Wound Membrane (SWM) Modules: Characterization, Improved Geometrical Characteristics,Novel Spacer Designs [MEDRC project] 
  • Modeling Transport Phenomena: Spiral Wound Module, Hollow Fibers        

Membrane Fouling Studies (Organic, Colloidal, Biofouling)

  • Fouling in SWM Modules; characterization, modeling. Fouling Indices [MEDRC project] 
  • Fouling of UF, MF Membranes; pretreatment of RO feed-waters [EC projects]
  • Fouling Mitigation Methods

Membrane Scaling Studies

  • RO/NF Membrane Incipient Scaling; experiments and modeling [Saudi Aramco project III]
  • Scaling Mitigation Methods   

Development of Membrane Module and Process Simulators

  • Comprehensive simulation of steady state SWM module performance
  • Dynamic simulator of SWM and membrane desalination system performance

Membrane Surface Post-treatment

  • Post-treatment to restore/improve salt rejection [S. Aramco project I, patent application]

1.2  Novel Membrane Plant Monitoring Methods 

Membrane Element Performance Monitoring

  • SWM element performance monitoring (permeate) plant-wide [S. Aramco project II, patent application]
  • Monitoring other process parameters

Scaling propensity monitor in RO/NF plants

  • Online monitoring per pressure vessel  [S. Aramco project III]

Novel sensors for monitoring membrane processes

1.3  Membrane Bioreactors

Αctivated Sludge Characterization – MBR Performance studies

  • Fouling studies in long-term MBR operation   [GSRT project]
  • Meta-genomics studies of sludge evolution  [Collaborationwith INEB/CERTH]
  • Development of Convenient and “Comprehensive” MBR monitoring techniques
  • MBR modeling 

  Novel MBR-based Processes  

  • MBR alone, or in combination with other membrane separations (e.g. MD), adapted to specific classes of bio-processes[GSRT project]

1.4  Novel Membrane-based Processes   

Membrane Distillation (MD) for Water Treatment and Separations

  • MD for bio-ethanol production/separation [GSRT project]
  • Combined MD with renewable energies for desalination

 Pressure Retarded Osmosis (PRO)– Forward  Osmosis (FO)

  • Innovative module design
  • Process development

 Recovery of valuable products   [GSRT projects]

  •  Membrane extraction  [PhD thesis]
  • UF – NF – RO hybrid separation processes
  • Algae harvesting