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At what percent rejection should the RO membranes be replaced? 

Membrane
Reverse osmosis
Nanofiltration
Water treatment
Desalination

Answers from top 10 papers

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Papers (10)Insight
Journal Article•DOI
A Path to Ultraselectivity: Support Layer Properties To Maximize Performance of Biomimetic Desalination Membranes
Jay R. Werber, Cassandra J. Porter, Menachem Elimelech 
14 Aug 2018-Environmental Science & Technology
34 Citations
In particular, RO membranes as support layers would enable >99.85% salt rejection at ∼10000-fold greater biomimetic-layer defect area than for porous supports.
Journal Article•DOI
Fabrication of a dual-layer (CA/PVDF) hollow fiber membrane for RO concentrate treatment
Tian-Yin Liu, Chen-Kai Li, Pang Bo, Bart Van der Bruggen, Xiaolin Wang 
01 Jun 2015-Desalination
21 Citations
The feasibility of treating RO concentrates by the resultant membrane was proven by the effective removal of total organic compounds (> 90%) and low rejection of total dissolved salts (
Journal Article•DOI
Structural optimization of osmosis processes for water and power production in desalination applications
Ali Almansoori, Yousef Saif 
01 Jul 2014-Desalination
26 Citations
This is an undesirable condition for the RO operation and it is suggested from our results that high performance PRO membrane with high water permeation and salt rejection may eliminate this condition.
Journal Article•DOI
Understanding the dependence of contact angles of commercially RO membranes on external conditions and surface features
Qiang Li, Qiang Li, Xianhui Pan, Zijian Qu, Xulong Zhao, Yan Jin, Hongjun Dai, Bo Yang, Xuliang Wang 
15 Jan 2013-Desalination
41 Citations
The experimental results suggest that the sample pretreatment makes the hydrophilicity of RO membranes decrease, because of the part removal of physically coated hydrophilic aliphatic alcohols and protect agents introduced in the synthesis process.
Journal Article•DOI
Impacts of silica on the sustainable productivity of reverse osmosis membranes treating low-salinity brackish groundwater
Mohammad Badruzzaman, Arun Subramani, James DeCarolis, William Pearce, Joseph G. Jacangelo 
15 Sep 2011-Desalination
53 Citations
The results suggested that due to the presence of high silica, operational flux and recovery were limited to 16.9 Lm− 2 h− 1 and 75%, respectively, for both RO membranes.
Journal Article•DOI
Free chlorine exposure dose (ppm·h) and its impact on RO membranes ageing and recycling potential
Raquel García-Pacheco, Raquel García-Pacheco, Raquel García-Pacheco, Junkal Landaburu-Aguirre, Amaia Lejarazu-Larrañaga, Amaia Lejarazu-Larrañaga, Laura Rodríguez-Sáez, Laura Rodríguez-Sáez, Serena Molina, Thomas Ransome, Eloy García-Calvo, Eloy García-Calvo 
01 May 2019-Desalination
34 Citations
However, it can be used consistently to convert end-of-life RO membrane into NF-like recycled membranes using concentrations higher than 10 ppm.
Journal Article•DOI
Surface modification of reverse osmosis membranes with zwitterionic polymer to reduce biofouling
Ahmed E. Abdelhamid, Mahmoud M. Elawady, Mahmoud Ahmed Abd El-Ghaffar, A. M. Rabie, Poul Larsen, Morten Lykkegaard Christensen 
01 Oct 2015-Water Science & Technology: Water Supply
20 Citations
This in situ surface treatment approach for RO membranes could be very important for modifying membranes in their original module assemblies as it increases water production and reduces the salt content.
Journal Article•DOI
Assessing potential of nanofiltration, reverse osmosis and membrane distillation drinking water treatment for pharmaceutically active compounds (PhACs) removal
Carolina Fonseca Couto, Amanda Vitória Santos, Míriam Cristina Santos Amaral, Liséte Celina Lange, Laura Hamdan de Andrade, Ana Flávia Souza Foureaux, Bárbara Stella Fernandes 
01 Feb 2020-Journal of water process engineering
60 Citations
The results show that the PhACs rejection by NF and RO membranes decreases as the permeate recovery rate (RR) increases.
Journal Article•DOI
Chemical treatment for improved performance of reverse osmosis membranes
Debabrata Mukherjee, Ashish Kulkarni, William N. Gill 
01 May 1996-Desalination
89 Citations
Therefore enhancement by short-term chemical treatment may be a very useful approach for the future development of RO membranes having higher flux and rejection.
Journal Article•DOI
The application of microfiltration-reverse osmosis/nanofiltration to trace organics removal for municipal wastewater reuse.
N. Garcia, J. Moreno, Elise Cartmell, Ignasi Rodríguez-Roda, Simon J. Judd 
29 Nov 2013-Environmental Technology
47 Citations
Differences in pilot plant and full-scale data were otherwise attributed to the impact of membrane ageing (and specifically hydrolysis) on RO rejection of the MPs examined.

Related Questions

Scaling cause rejection of membrane drop ?5 answersScaling in membrane systems can indeed lead to a drop in membrane performance and rejection. Various factors contribute to scaling, including the presence of sparingly soluble salts like calcium, barium, strontium, and silica, which can result in irreversible membrane damage and reduced permeate quality. Methods such as using antiscalants or incorporating carbon nanotubes into membranes have shown promise in reducing scaling effects and improving membrane performance. Inorganic scaling, caused by minerals like calcium carbonate and sulfate, is a common issue in membrane-based desalination, impacting water recovery and process efficiency. Additionally, scaling can affect the liquid entry pressure of membranes in processes like membrane distillation, potentially leading to increased salt passage and decreased separation effectiveness. Addressing scaling is crucial to maintaining membrane efficiency and preventing rejection.
Is reverse osmosis membrane rejection rate applies to bacteria?5 answersReverse osmosis (RO) membranes can indeed exhibit rejection rates towards bacteria. Studies have shown that RO membranes can effectively reject bacteria, with varying degrees of efficiency depending on the membrane type and operating conditions. Research has demonstrated that modified RO membranes, incorporating antibacterial agents like myrrh, exhibit high resistance to bacterial growth compared to unmodified membranes. Additionally, investigations have highlighted the successful removal of specific microbes, including total coliforms and faecal coliforms, by RO systems, achieving total rejection of all received bacteria. Furthermore, pilot-scale studies have assessed the passage of bacteria through RO membranes, indicating that RO membranes can significantly remove bacteria, with rejection percentages ranging from 99.92% to 99.999%. Therefore, the rejection rate of RO membranes can indeed apply to bacteria, showcasing their potential in microbial removal.
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