RO Membrane Fouling Prevention

In-situ generated peroxyformic acid compositions for cleaning and preventing biofouling on membranes without damaging the membranes. The compositions contain peroxyformic acid, a powerful oxidant and antimicrobial, that is generated on-site. The compositions are used to clean membranes for separation processes like filtration, desalination, etc. by contacting the membranes with the peroxyformic acid solution. The compositions remove biofilms, foulants, and mineral scales from membranes without causing membrane incompatibility issues. The in-situ generation allows on-demand production of the peroxyformic acid without shipping and storing pre-made compositions.

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Reverse osmosis membranes for desalination applications with improved salt rejection and fouling resistance compared to conventional membranes. The membranes are manufactured using a unique process that involves depositing layers onto a substrate by sequentially filling and draining a vessel with solutions containing materials like nanotubes and polymers. The process allows settling of nanotubes and interfacial polymerization to form smooth, dense layers with nanotube networks. The resulting membranes have reduced surface roughness, pore size, and fouling compared to conventional membranes.

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Spiral wound membrane filter elements with reduced pressure drop and fouling compared to conventional elements. The elements have stacked permeate spacer layers instead of a single layer. The layers are separated by deposited features like protrusions that create low-resistance flow paths between the layers. This replaces the traditional feed spacer mesh. Embossed features in the layers also provide spaces in the brine feed channel to reduce flow restriction. This reduces pressure drop and fouling compared to conventional elements with a single permeate spacer layer and feed spacer mesh.

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A self-cleaning nanofiltration membrane that uses a composite of graphitic carbon nitride (G-CN) and polypyrrole (PPy) for water decontamination and desalination applications. The composite membrane has improved fouling resistance compared to pristine G-CN membranes due to the photocatalytic properties of PPy. When exposed to visible light, the PPy component in the composite membrane self-cleans by degrading foulants like dyes and salts. The composite membrane also has good water flux and salt rejection properties.

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Membrane fouling poses a significant challenge in the widespread adoption and cost-effective operation of membrane technology. Among different strategies to mitigate fouling, dynamic (DM) technology has emerged as promising one for effective control mitigation fouling. Silicon carbide (SiC) membranes have attracted considerable attention materials due their remarkable advantages, yet is still inevitable challenging separation tasks, such oil-in-water (O/W) emulsion separation, thus essential maximize economic viability. This study investigates use pre-deposited oxide DMs SiC during O/W emulsions. five screened oxides (Fe2O3, SiO2, TiO2, ZrO2, Al2O3), SiO2 most DM material its favorable combination particle size, negative surface charge, hydrophilicity, underwater oleophobicity, leading minimized oil droplet adhesion via electrostatic repulsion surfaces enhanced antifouling performance. Parameter optimization dead-end mode revealed deposition amount 300 g/m2, transmembrane pressure (TMP) 0.25 bar, backwashing 2 bar ideal conditions, achieving stable rejection (~93%) high pure water fl... Read More

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Polymer membrane for water treatment with reduced fouling and improved performance by incorporating a natural polysaccharide called carrageenan into the membrane matrix. The carrageenan, sourced from seaweed, enhances membrane hydrophilicity, surface charge, and fouling resistance to minimize fouling when used in water treatment applications. The carrageenan is loaded at 0.5-4 wt% in the polymer layer to achieve fouling reduction without compromising membrane permeability.

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Although membrane technology has been widely applied in water treatment, fouling is an inevitable issue that largely limited its application. Benefiting from the advantages of green power, easy integration and low chemical consumption, electrocatalytic (ECM) received attention, using it to enable electrically driven self-cleaning performance recently, making highly desirable for sustainable control. In this work, we comprehensively summarized conventional (e.g., carbonaceous materials, metal oxide) emerging metalorganic framework MXene) materials fabrication ECM. Then methods operating modes ECM were emphasized. Afterwards, application different control was highlighted corresponding mechanism revealed. Based on existing research findings, proposed challenges future prospects practical This study provides enlightening knowledge into development

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Composite membrane for desalination applications that has improved fouling resistance and stability over long periods compared to conventional membranes. The composite membrane has a porous support layer, a thin polyamide separation layer on top, and a coating layer on the separation layer. The coating layer has a water contact angle of 40° or less and a protein adsorption force of 0.4 nN or less. The low contact angle and adsorption force of the coating layer reduce fouling compared to conventional membranes.

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A membrane for water treatment that reduces fouling and improves flux compared to traditional membranes. The membrane has a unique interface design with a reduction in dimensional properties toward the retentate outlet. This creates higher cross-flow velocities to disrupt concentration polarization and prevent fouling. The membrane is also manufacturable by 3D printing to enable customization and optimization. The 3D printing allows tuning of the interface geometry and pore structure for improved fouling resistance. The membrane can also be used in water treatment modules and systems for reducing divalent ion concentrations.

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Sugar production generates wastewater rich in dissolved solids and organic matter, improper disposal poses severe environmental risks, exacerbates water scarcity, creates regulatory challenges. Conventional treatment methods, such as evaporation chemical precipitation, are energy-intensive often ineffective at removing fine particulates impurities. This study evaluates membrane-based separation a sustainable alternative for reclamation sugar recovery from industry effluents, focusing on replacing with membrane processes, ensuring high permeate quality, mitigating fouling. Cross-flow filtration experiments were conducted lab-scale system 70 C to suppress microbial growth, comparing direct reverse osmosis (RO) of the raw effluent an integrated ultrafiltration (UF)RO process. Direct RO resulted rapid fouling, which was characterized via SEM, EDS, FTIR elucidate fouling mechanisms. A tight UF (5 kDa) pre-treatment before significantly mitigated improved performance, enabling 75 % recovery, maintaining conductivity below 0.5 mS/cm, sustaining stable flux, reducing blocking.

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ABSTRACT The reverse osmosis (RO) process has been a leading technology in the desalination field; however, an inevitable occurrence of membrane fouling during operation reduces their efficiency cost and productivity. Autopsy regarded as practical effective approach to examining RO conditions foulant properties. Herein, we investigated behaviors membranes pilot-scale brackish water (BWRO) system after 142 h through autopsies layer characterization. X-ray diffraction (XRD) patterns disclosed Si Al minerals responsible for inorganic foulants, while Fourier-transform infrared (FT-IR) spectra indicated presence organic including polysaccharides proteins. Biofouling, such coliform, was also detected using liquid-medium culture technique. In addition, fouled decontaminated by chemical cleaning process, three steps acidic with Hydrex 4703, alkaline 4506, neutral water. feed pressure permeate flux were regenerated over 96%. This study may have fundamental implications proposing appropriate pretreatment setup

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Determining and executing a self-contained membrane cleaning cycle for a spacecraft water treatment system without human intervention. The cleaning strategy is optimized based on operational sensor data, historical cleaning data, and forecast fouling analysis. An AI model learns cleaning sequences from training data. The AI processes sensor data to determine cleaning cycles and sequences for a membrane. This automated cleaning strategy maximizes membrane performance recovery while minimizing resources compared to manual cleaning.

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Film evaluation system and method to accurately assess the health of reverse osmosis membranes used in water treatment. The system uses real-time measurements, adaptive algorithms, and flux comparisons to calculate diffusion rates and flow resistances that indicate membrane fouling and degradation. This allows determining the membrane's health state. The system also calculates optimal operating pressures and water recovery rates to minimize energy consumption in membrane treatment.

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Membrane fouling remains a persistent challenge in reverse osmosis (RO) systems. Devising effective strategies to mitigate membrane has become crucial for sustainable water treatment. Here, we propose titanium-based pre-coagulation strategy RO mitigation through regulation of the microbial habitat feed. The performance Ti(SO4)2 desulfurization wastewater and subsequent mechanism were systematically investigated. Our findings revealed that Ti induced an acidized environment, maintained balance between organic inorganic depositions, fostered beneficial community resisted rapid fouling. 20 day operations different scenarios (Ti, Al, Ctrl) showed group membranes highest normalized flux at 57.15%, outperforming Ctrl Al groups by 7.92% 15.16%, respectively. Microbial analyses, including taxonomic profiling metagenomic analysis, demonstrated Ti-based reduced dominance extracellular polymeric substance (EPS)-secreting genera, such as Sphingopyxis, while promoting Terrimonas Paenarthrobacter, with acid-tolerance traits EPS production. This shift mitigated biofouling enhancing limiting biofilm... Read More

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Peroxyformic acid compositions for cleaning membranes used in filtration processes like reverse osmosis to remove biofilms and mineral deposits without damaging the membranes. The compositions are generated onsite using peroxyformic acid as a cleaning agent instead of conventional acidic or alkaline solutions. The peroxyformic acid efficiently kills and removes biofilms and minerals from membranes without negatively affecting the membrane material.

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Nowadays, reverse osmosis (RO) desalination has become a highly effective and economical solution to address water scarcity worldwide. The membranes used in this type of separation are influenced by both pre-treatment operations feed quality, leading fouling, complex phenomenon responsible for reducing treatment performance shortening membrane lifespan. In study, an autopsy RO from the Boujdour plant was performed, fouling prediction tool based on transmembrane pressure (TMP) developed using MATLAB/Simulink (R2015a) with artificial neural network (ANN) model. impact also examined through one year monitoring. A detailed analysis fouled conducted SEM/EDS techniques characterize membranes surface cross-section. results revealed significant fractures surface, predominantly consisting organic deposits (characterized high oxygen concentration 39.69%) inorganic including Si (7.99%), Al (2.79%), Mg (1.56%), Fe (1.27%), smaller quantities K (0.87%), S (0.36%), Ca (0.12%). ANN model predicting successfully developed, achieving R2 value 92.077% low mean square error (MSE) 0.005657. This pred... Read More

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Reverse osmosis (RO) desalination technology offers a promising solution for mitigating water scarcity. However, one of the major challenges faced by RO membranes is biofouling, which significantly increases costs. Traditional simulation models often overlook environmental variability and do not incorporate effects membrane-surface modifications. This paper develops bacterial growth model prediction seawater performance, applicable to commercial membranes, can be either uncoated or coated with iron nanoparticles (FeNPs nZVI). FeNPs were selected due their known antimicrobial properties potential mitigate biofilm formation. The native bacterium Bacillus halotolerans MCC1 was used as biofouling bacterium. Growth kinetics determined at different temperatures (from 26 50 C) pH values 4 10) obtain parameters. Microbial on modeled using Monod equation. performance evaluated in terms hydraulic resistance permeate flux under clean biofouled conditions. validated data obtained laboratory scale. Bacteria grew faster 42 C 10. had more significant effect than temperature rate. FeNP-coated ex... Read More

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Operating a two-stage desalination system to prevent performance degradation without chemical cleaning. The method involves alternating between two water passing patterns. In the first pattern, water is fed to the first stage, concentrated there, and then fed to one of the second stage units. The other second stage unit receives diluted water instead. This is switched with the second pattern every 30-180 minutes. This allows the second stage units to periodically process lower-concentration feeds to prevent scale buildup.

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An inorganic membrane with a hierarchical pore structure and patterned surface that enhances filtration flux and reduces fouling in water and wastewater treatment. The membrane has multiple layers with gradually decreasing pore sizes. The outer layers have larger pores and the inner layer closest to the feed has the smallest pores. This gradient structure prevents fine particles from the active layer clogging the substrate. The patterned surface on the active layer further improves flux and antifouling by creating extra surfaces and turbulence. The membrane is made by depositing layers with controlled pore sizes and then 3D printing or imprinting a pattern on the active layer.

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Membrane biofouling is one of the most persistent challenges faced by desalination plants, particularly those utilizing reverse osmosis (RO) technology. Addressing this issue crucial to reduce maintenance costs, improve efficiency, and extend lifespan membranes. This study introduces SpectroMarine, an advanced optical water quality sensor that provides real-time data on organic content biomass levels, enabling operators take proactive measures for key parameters such as chlorophyll, total carbon oxidization agent prevent biofouling. The combines fluorescence absorption spectroscopy with Internet Things (IoT) integration, offering immediate analytics actionable insights. Field tests demonstrated significant potential reducing operational energy consumption, optimizing chemical use according quality, ultimately enhancing plant performance. paper discusses sensors design, application, outcomes, providing a roadmap revolutionizing monitoring in plants.

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Filter structure design for water purifiers that improves cleaning efficiency and prevents adsorption between components. The filter has wound membranes, a spacer, and a seal assembly around them. The membranes are spaced apart along the radial direction when wound around the tube. This creates gaps between the membranes for cleaning fluid to flow through. The seal assembly has a harder material than the membranes to prevent adsorption. This allows reliable cleaning and prevents blocking. The spacer maintains space between membranes. An adapter connects the tube to the spaced membranes. The design improves cleaning efficiency, prevents adsorption, and simplifies manufacturing compared to prior art.

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Optimizing reverse osmosis water desalination systems using machine learning to reduce operating costs and improve performance by predicting when to clean the membranes. The system measures parameters like feed pressure, flow, salinity, temperature, etc. and uses a trained ML model to determine fouling levels and optimize flow rates through the stages. This allows reducing energy use while maintaining permeate production. By predicting when fouling will inflect and decline, cleaning can be timed to minimize energy vs waiting for a 10% flux drop. The ML model also balances flow across stages for energy savings.

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Biocide compositions and methods for maintaining, cleaning, and defouling reverse osmosis membranes using a stabilized hypochlorous acid solution containing a bromide ion source. The stabilized hypochlorous acid solution forms small amounts of bromine in situ that effectively control biofouling without harming sensitive membranes. The biocide composition can be used as an online biocide to prevent fouling in reverse osmosis systems, as well as for offline cleaning of fouled membranes.

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Reverse osmosis filter system that improves efficiency and longevity compared to conventional RO filters. The system uses additional components like pre-filters, turbines, and end cap filters to more effectively remove impurities and prevent clogging. The components are arranged inside the filter housing in a specific order. This configuration allows larger impurities to be trapped and separated out before reaching the RO membrane, reducing membrane fouling. The turbine component generates fluid flow to help flush out impurities. The end cap filter catches any remaining particles before exiting the system.

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Filtration membrane unit and holder configuration that improves membrane cleaning maintainability by balancing filtrate flow rates across the membrane. The membrane unit has a socket that extends laterally and has an end inserted into a recess. The socket has two discharge ports, one on each side of the center, instead of just one at the end. This balances the suction force and filtrate flow rates across the membrane, preventing clogging from uneven flow.

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Water treatment method and apparatus to prevent biofouling of reverse osmosis (RO) membranes without harming the membranes. The method involves intermittently adding biocides to the water feed to the RO membrane. The biocide dose and frequency are adjusted based on membrane fouling levels. This prevents excessive biocide concentrations that can harm the membrane. The biocide addition is tuned to keep oxidation potential below a threshold without exceeding it. This prevents biocide-induced membrane fouling while still providing adequate biocide dosing to prevent organic growth.

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ABSTRACT The lack of safe drinking water infrastructures in off-grid communities is a significant risk to sustainable development, especially for low- and middle-income countries (LMICs). Photovoltaic-powered reverse osmosis (PVRO) has emerged as promising method due its performance, scalability, consistency, the robust global supply chain components. However, reliability issues like biofouling can quickly reduce shorten membrane lifetime, hinder adoption settings. Ultraviolet light-emitting diodes (UV-LEDs) ranging from 200 285 nm wavelengths have been shown number microorganisms by damaging their DNA, but there are mixed results about use mitigating systems. Herein, we aim provide preliminary assessment challenges associated with using UV-LEDs pre-treatment measure PVRO systems whether it curb feedwater, thereby For experimental evaluation, bacterial feedwater was prepared Escherichia coli ATCC 11229. Batch experiments Petri dishes 275 UV-LED radiometer showed non-uniform illumination target region, indicating need optimizing reactor design consistent dosage. Optical density measur... Read More

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Osmotic membrane separation system with feed and draw recirculation loops in each module to improve efficiency and prevent fouling. The system has a series of osmosis modules where feed and draw solutions are circulated co-currently through each module. Feed recirculation loops connect feed inlet to outlet of each module. Draw recirculation loops connect draw inlet to outlet. This allows controlled flow rates, solute concentrations, and hydrostatic pressures in each loop. The bulk feed and draw streams flow counter-currently through the system as a whole. The recirculation loops prevent boundary layer buildup and fouling. They also allow mixing of partially concentrated streams to reduce driving force and enhance membrane efficiency.

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Filter leaf for reverse osmosis filters with raised features on the membrane surface that enhance filtration performance and cleaning efficiency. The raised features are formed directly on the membrane using printing or embossing techniques. The feature configuration optimizes flow characteristics during normal filtration and reverse flushing. During filtration, the features induce higher velocities to resist fouling. During flushing, they induce higher velocities for scouring. This eliminates the need for cleaning chemicals and allows using reverse flow for cleaning.

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Method and inhibitor for suppressing silica fouling in reverse osmosis membrane systems. The method involves adding an acrylic acid-based polymer and/or a maleic acid-based polymer, along with a combined chlorine-based oxidizing agent and/or a combined bromine-based oxidizing agent, to the water being treated. This combination helps prevent silica fouling on both the concentrate and feed sides of the membrane. The acrylic/maleic acid polymers inhibit scale formation, while the oxidizing agents clean the membrane surface.

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Composition and membrane coating for preventing biofouling and reducing membrane fouling in water filtration. The composition contains a polymer blend with one component having lower water solubility than the other. The blended polymer forms fibers via electrospinning. Anti-quorum sensing molecules like Urolithin A are associated with the fibers. The composition releases the anti-quorum sensing molecules over time. The coated membranes have reduced biofilm formation compared to uncoated membranes. The blended polymer enables controlled release of the anti-quorum sensing molecules from the fibers.

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A simple and effective reverse osmosis membrane cleaning method and agent that can clean and sterilize the membrane in a single step using a composite cleaning solution containing hydrochloric acid, citric acid, surfactant, and bactericide. The method involves circulating this cleaning solution through the membrane system at elevated temperature to remove inorganic scale, organic fouling, and bacteria. The citric acid complexes with ions to enhance scale removal, the hydrochloric acid provides initial cleaning, and the surfactant and bactericide prevent re-fouling. This one-step cleaning eliminates the need for multiple cleaning steps and allows rapid and effective membrane restoration.

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Real-time monitoring of reverse osmosis (RO) membrane fouling to enable early detection, characterization, and mitigation of fouling. The technique involves isolating the permeate of a lead or tail element in each stage of an RO system and measuring its flux and rejection directly. This provides much higher sensitivity and faster detection of fouling compared to monitoring the entire stage or system. By isolating the lead or tail element permeate and measuring its performance, fouling can be detected several times faster. This allows for more targeted and effective fouling management strategies.

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Cleaning method for reverse osmosis membranes fouled by proteins and polysaccharides to restore water production. The cleaning process involves four steps: (1) cleaning with citric acid and sulfamic acid, (2) cleaning with urea and surfactant, (3) cleaning with sodium tripolyphosphate and sodium citrate, and (4) repeating step 1. The cleaning steps use specific chemical solutions and pH ranges to effectively remove the protein and polysaccharide fouling from the reverse osmosis membranes.

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Cleaning nanofiltration membranes using microbubbles to improve cleaning effectiveness and reduce fouling compared to conventional cleaning methods. The method involves preparing cleaning water with microbubbles by dissolving gases into the cleaning solutions. The microbubbles are used to clean the membranes by rinsing, acid cleaning, alkaline cleaning, and repair agent cleaning steps. This microbubble cleaning process provides better fouling removal and membrane recovery compared to traditional cleaning methods.

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Reverse osmosis membrane cleaning device and method for online cleaning of RO membranes to improve performance and prolong membrane life. The device has a cleaning unit, production unit, dosing unit, bypass monitoring unit, and control unit. The method involves diagnosing membrane fouling based on factors like water quality changes, then triggering cleaning modes tailored to the fouling type. Cleaning mode 1 is for inorganic fouling with calcium, magnesium, carbonate, and chloride. Cleaning mode 2 is for fouling with sulfate, fluoride, and organic compounds. The cleaning solutions contain acids, alkali, salts, and biocides. The device automatically dispenses the optimized cleaning solutions based on the diagnosis.

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A reverse osmosis membrane cleaning agent for organic fouling that effectively removes organic matter, microorganisms, and dirt from membrane surfaces. The cleaning agent contains specific components in optimized proportions. These include: 1% anionic surfactant (like sodium dodecyl benzene sulfonate), 25-35% chelant (like EDTA), 8-10% antioxidant, 0.1-0.3% aprotic solvent (like N-methylpyrrolidone), 0.5-1% fungicide (like 2,2-diao-3-nitropropionamide), and pH adjuster as needed. The components are chosen for their synergistic fouling removal properties. The anionic surfactant helps strip biological slime, chelant removes

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Cleaning method for desalinated reverse osmosis membranes in water treatment systems to maintain membrane performance and prevent fouling. The cleaning involves specific steps based on the type of contamination. For organic fouling, alkaline cleaning is followed by acid cleaning. For inorganic scale fouling, acid cleaning is followed by alkaline cleaning. The cleaning steps include soaking the membranes in cleaning solutions, rinsing with water, and using high quality water without residual chlorine.

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A liquid separation membrane with improved fouling resistance for applications like reverse osmosis and ultrafiltration. The membrane has a base material with a porous layer and a coating layer that covers part of the surface. The coating layer contains an oil-repellent polymer. The oil-repellent polymer can contain fluorine-containing monomers and/or antibacterial monomers. The coating layer adheres to the base material via forces like crosslinking, van der Waals, ionic, hydrogen bonding, and anchoring. The membrane prevents fouling by reducing protein adsorption and oil accumulation on the surface.

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A method for cleaning reverse osmosis membranes in water treatment systems to improve cleaning efficiency and prevent dirt transfer between stages. The method involves sequentially flushing and soaking each membrane section with acidic, neutral, and alkaline cleaning agents. The membranes are separated during cleaning to prevent dirt from front stages washing into later stages. This prevents excessive sediment buildup and maintains membrane performance.

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Water treatment method for improving water quality in a membrane filtration system. The method involves adjusting the chemical cleaning conditions of the membrane based on the Silt Density Index (SDI) of the filtered water. When the SDI exceeds a reference range, the chemical cleaning frequency, contact time, concentration, temperature are adjusted to improve filtration performance. By changing the cleaning conditions based on the SDI, it allows optimizing the cleaning parameters to maintain water quality when the SDI deviates from the reference range.

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Online reverse osmosis membrane cleaning method and device that allows removing fouling from operating reverse osmosis membrane modules without disassembly. The cleaning involves cyclic alkaline washing, pickling, and flushing. The method improves membrane flux recovery and fouling removal compared to offline cleaning. The device connects to the membrane module's concentrate outlet and feed inlet. It pumps cleaning solutions through the module during operation. The alkaline wash removes organic matter, pickling dissolves inorganic deposits, and flushing rinses.

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An improved method for chemically cleaning reverse osmosis membranes to prevent fouling buildup that can clog the membranes and reduce performance. The method involves circulating the cleaning solution from the back of the membrane array towards the front during chemical cleaning, instead of feeding from the front as in traditional cleaning. This prevents front-end fouling from blocking the back-end grid channels during cleaning. The cleaning solution is circulated using the membrane element's former pump to reverse the flow direction.

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Composite reverse osmosis membranes for water purification and desalination have improved fouling resistance and water permeability. The membranes have a modified polyamide skin layer on a porous support. The modification is done by treating the polyamide with an alkylenediamine derivative after interfacial polymerization. This modification improves the antifouling properties of the membrane compared to unmodified polyamide membranes.

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Preparing an anti-fouling, wetting-resistant composite membrane distillation membrane to improve performance and stability of membrane distillation systems for treating high-salt wastewater. The method involves modifying the surface of hydrophobic microporous membranes to make them more hydrophilic, then coating them with a mixture of tannic acid and polyvinyl alcohol. This composite membrane has both oil pollution resistance and surfactant wetting resistance. The hydrophilic coating prevents foulants from adhering to the membrane and blocking pores, while the tannic acid provides oleophobicity to prevent oil passage. The composite membrane maintains high flux and rejection for long-term operation stability.

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A chemical cleaning system for high organic fouling membrane elements in reverse osmosis and nanofiltration systems used to treat organic wastewater. The system allows efficient chemical cleaning of multiple sections of membranes without disassembly. The membrane sections are connected in series and a cleaning pool is added between sections. Cleaning agents like disinfectants, phosphates, and acids are added to the pool and circulated through the sections. This allows targeted cleaning of fouled sections without disassembly and reduces overall cleaning agent usage.

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High-efficiency two-stage RO water treatment system that improves efficiency, reduces energy consumption, and extends membrane life compared to conventional two-stage RO systems. The system has a pre-treatment unit, a secondary RO unit, a post-treatment unit, and separate flushing and cleaning units. The pre-treatment unit sterilizes and scales the feed water before sending it to the secondary RO unit. The secondary RO unit has dedicated flushing water to prevent membrane fouling. The cleaning unit provides chemical cleaning water to periodically clean the secondary RO membranes. This prevents fouling, maintains efficiency, reduces operating pressure, and extends membrane life compared to shared flushing in conventional two-stage RO systems.

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Polyamide reverse osmosis membrane with excellent durability and antifouling properties for desalination applications. The membrane has a layered structure with a polymer support layer, a polyamide active layer, an antifouling layer, and a protective coating. The antifouling layer contains a crosslinked polymer made from a primary amine compound and a polyfunctional acid halide. This layer provides antifouling resistance. The protective coating prevents chlorine degradation. The layered structure improves membrane durability and fouling resistance compared to traditional membranes.

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Preventing reverse osmosis membrane fouling for water purification with enhanced performance. The membranes have a protective layer made from a composition containing a specific polymer material that improves salt and boron rejection while maintaining high flux. The composition includes a material with a specific chemical formula, molecular weight, optional hydrophilic polymers, and crosslinking agents.

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A thin-film composite polyamide reverse osmosis membrane with improved fouling resistance and an efficient preparation method using metal-organic frameworks for water purification. The membrane has antibacterial and anti-biofouling properties to prevent fouling and extend membrane life. The method involves loading a specific metal-organic framework (CuBTTri) into a polyamide thin film on an ultrafiltration membrane substrate.

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