Advanced Membrane Fouling Characterization in Full-Scale Reverse Osmosis Processes

2010 ◽  
pp. 101-134
Author(s):  
Lianfa Song ◽  
Kwee Guan Tay
Keyword(s):  
Reverse Osmosis ◽  
Membrane Fouling ◽  
Full Scale

scholarly journals Clinical Autopsy of a Reverse Osmosis Membrane Module

2021 ◽  
Vol 3 ◽  
Author(s):  
Graciela Gonzalez-Gil ◽  
Ali Reza Behzad ◽  
Andreia S. F. Farinha ◽  
Chengyan Zhao ◽  
Szilard S. Bucs ◽  
...  
Keyword(s):  
Reverse Osmosis ◽  
Membrane Fouling ◽  
Full Scale ◽  
Operating Pressure ◽  
Reverse Osmosis Membrane ◽  
Polysulfone Membrane ◽  
Membrane Area ◽  
Microbial Cells ◽  
Imaging Results ◽  
Starting Point

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.

Comparison of reverse osmosis membrane fouling characteristics in full-scale leachate treatment systems with chemical coagulation and microfiltration pre-treatments

2014 ◽  
Vol 71 (4) ◽  
pp. 580-587 ◽  
Author(s):  
Weerapong Rukapan ◽  
Benyapa Khananthai ◽  
Thirdpong Srisukphun ◽  
Wilai Chiemchaisri ◽  
Chart Chiemchaisri
Keyword(s):  
Reverse Osmosis ◽  
Membrane Fouling ◽  
Full Scale ◽  
Permeate Flux ◽  
Leachate Treatment ◽  
Chemical Coagulation ◽  
Cake Layer ◽  
Ro Membrane ◽  
Pre Treatment ◽  
Fouling Characteristics

Fouling characteristics of reverse osmosis (RO) membrane with chemical coagulation and microfiltration (MF) pre-treatment were investigated at full-scale leachate treatment systems. In chemical coagulation pre-treatment, solid separation from stabilized leachate was performed by ferric chloride coagulation followed by sand filtration. Meanwhile, MF pre-treatment and the RO system utilized direct filtration using a 0.03 µm membrane without chemical addition. MF pre-treatment yielded better pollutant removals in terms of organics and nitrogen. The study on effect of pre-treatment on RO membrane fouling revealed that accumulated foulant on the RO membrane in MF pre-treatment was significantly lower than that of chemical coagulation. Nevertheless, NaOH cleaning of the fouled RO membrane after chemical coagulation pre-treatment could better recover its permeate flux, thus suggesting that the formation of a loose-structure cake layer by chemical coagulation pre-treatment could allow effective penetration of chemical cleaning and detachment of foulant layer from the membrane surface.

Low cost reclamation using the Advanced Integrated Wastewater Pond Systems® Technology and reverse osmosis

2002 ◽  
Vol 45 (1) ◽  
pp. 117-125 ◽  
Author(s):  
J.B. Downing ◽  
E. Bracco ◽  
F.B. Green ◽  
A.Y. Ku ◽  
T.J. Lundquist ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Reverse Osmosis ◽  
Membrane Fouling ◽  
Low Cost ◽  
Full Scale ◽  
Soluble Nitrogen ◽  
Wastewater Reclamation ◽  
Dissolved Air Flotation ◽  
Conventional Activated Sludge ◽  
Separation Equipment

The sustainability of wastewater reclamation and reuse schemes is often limited by the increase in salt concentration that occurs with each water use. In this pilot study, we show that the cost of reclaiming wastewater and removing salt can be dramatically decreased by integrating recent advances in wastewater pond design, solids separation equipment, and membrane technology. Effluent from an AIWPS® Facility was clarified in a Krofta® SupracellTM Dissolved Air Flotation (DAF) unit and a Slow Sand Filter (SSF) prior to final treatment in an Expertise S.r.l. reverse osmosis (RO) unit. The ponds of the AIWPS® Facility removed an average of 82% of soluble BOD and 80% of soluble nitrogen. Following clarification, filtration, and RO treatment, the pollutant removals were > 99% for soluble BOD, > 99% for soluble nitrogen, and 98% for TDS. Based on membrane fouling rate data, the cleaning interval for the RO membranes in a full-scale AIWPS®-RO Facility would be over 100 days. This interval is on par with that typically seen in full-scale reclamation facilities treating secondary activated sludge effluent with microfiltration prior to reverse osmosis. A 4-MLD AIWPS®-RO Facility is expected to produce permeate water at substantially lower cost and lower energy consumption (US $698 and 443 kWh per million liters treated) than a system of equal capacity using conventional activated sludge secondary treatment followed by microfiltration and reverse osmosis (US $1274 and 911 kWh per million litres treated). This cost and energy differential is attributable to the lower capital and operating expenses of the AIWPS® Technology in comparison with activated sludge.

scholarly journals Membrane Fouling and Chemical Cleaning in Three Full-Scale Reverse Osmosis Plants Producing Demineralized Water

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Florian Beyer ◽  
Judita Laurinonyte ◽  
Arie Zwijnenburg ◽  
Alfons J. M. Stams ◽  
Caroline M. Plugge
Keyword(s):  
Reverse Osmosis ◽  
Membrane Fouling ◽  
Full Scale ◽  
Feed Water ◽  
Chemical Cleaning ◽  
Laboratory Setup ◽  
Plant Chemical ◽  
Plate Counts ◽  
Cleaning Procedures ◽  
Heterotrophic Plate Counts

Membrane fouling and cleaning were studied in three reverse osmosis (RO) plants. Feed water was secondary wastewater effluent, river water, and surface water. Membrane autopsies were used for fouling characterization. Fouling layer measurements included total organic carbon (TOC), adenosine triphosphate, polysaccharides, proteins, and heterotrophic plate counts. In all locations, membrane and spacer fouling was (bio)organic. Plant chemical cleaning efficiencies were evaluated from full-scale operational data and cleaning trials in a laboratory setup. Standard cleaning procedures were compared to two cleaning procedures specifically adapted to treat (bio)organic fouling using commercial blend cleaners (mixtures of active substances). The three RO plants were impacted by irreversible foulants causing permanently decreased performance in normalized pressure drop and water permeability even after thorough chemical cleaning. The standard plant and adapted cleaning procedures reduced the TOC by 45% on average, with a maximum of ~80%. In general, around 20% higher biomass removal could be achieved with adapted procedure I compared to adapted procedure II. TOC measurements and SEM showed that none of cleaning procedures applied could remove foulants completely from the membrane elements. This study underlines the need for novel cleaning approaches targeting resistant foulants, as none of the procedures applied resulted in highly effective membrane regeneration.

Removal of Residual Nutrients and Chemical Additives From Secondary Sewage by Reverse osmosis

1975 ◽  
Vol 10 (1) ◽  
pp. 101-109
Author(s):  
H. Kirk Johnston ◽  
H.S. Lim
Keyword(s):  
Reverse Osmosis ◽  
Membrane Fouling ◽  
Pilot Plant ◽  
Waste Treatment ◽  
Iron Chloride ◽  
Treatment Technique ◽  
Chemical Additives ◽  
Cellulose Acetate Membranes ◽  
Municipal Wastewaters ◽  
Nutrient Solutions

Abstract The suitability of reverse osmosis as a renovation technique for the treatment of municipal wastewaters has been assessed. Cellulose acetate membranes capable of 70% and 90% NaCl rejections were employed in both laboratory and pilot plant studies to evaluate the efficiency of this technique in removing the residual precipitant chemicals generally employed in phosphorus removal programs (iron chloride, alum, and lime) and the nutrients (phosphates, nitrates and ammonia) characteristic of municipal wastewaters. Secondary sewage and raw sewage as well as prepared nutrient solutions were employed in the course of this program. Both laboratory and pilot plant studies indicated consistently outstanding removal efficiencies for the species examined, almost independent of the nature of the waste solutions being treated. Permeation of the purified effluent was subject to significant reductions due to membrane fouling. This characteristic was most pronounced for the more permeable (less selective) membranes. Routine chemical and physical cleanings enable satisfactory flux levels to be maintained, thereby suggesting that reverse osmosis may become a viable municipal waste treatment technique.

scholarly journals Full-Scale Seawater Reverse Osmosis Desalination Plant Simulator

2020 ◽  
Vol 53 (2) ◽  
pp. 16561-16568
Author(s):  
Mariam Elnour ◽  
Nader Meskin ◽  
Khlaed M. Khan ◽  
Raj Jain ◽  
Syed Zaidi ◽  
...  
Keyword(s):  
Reverse Osmosis ◽  
Full Scale ◽  
Desalination Plant ◽  
Seawater Reverse Osmosis ◽  
Reverse Osmosis Desalination
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