Reverse Osmosis Process Control

Desalination system using osmotically assisted reverse osmosis (OARO) with split feed streams between stages to improve salinity reduction compared to traditional OARO and low-salt reverse osmosis (LSRRO) systems. The system has multiple OARO stages connected in series. After the first OARO stage, the concentrated stream is split, with one portion entering the second OARO stage depressurized and the other portion directly. This allows higher recovery and concentration compared to single-stage OARO or LSRRO. The diluate from the second stage is mixed with feed to the first stage. Adjusting split ratios and stage lengths optimizes performance. The system can further have features like mixing diluate with feed, using ERDs, or splitting diluate into feed and concentrate sides.

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Automated control system for producing injection water with optimized composition for enhanced oil recovery while minimizing formation damage. The system uses a desalination plant with RO and nanofiltration stages, a blending system, and a control panel. The control system adjusts valve positions based on user inputs and sensor data to maintain injection water composition within predefined operating envelopes for specific reservoir regions. This balances oil recovery vs formation damage risks by tailoring the water salinity, sulfate, and multivalent cation levels.

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The Reverse Osmosis (RO) system has the potential as a vibrant technology to generate high-quality water from brackish sources. Nevertheless, progressive growth in and electricity demands necessitates development of sustainable desalination technology. This can be achieved by reducing specific energy consumption process, which would also reduce environmental footprint. study proposes concept overall multistage multi-pass RO Arab Potash Company (APC) Jordan via heating feed water. utilisation waste heat generated different units production plant APC such steam condensate supplied exchanger is feasible technique entering system. To systematically assess contribution temperature on performance metrics including use, generic model developed. Model based simulation used evaluate effect temperature. results indicate clear enhancement while using temperatures close maximum recommended manufacture. It been noticed that an increase 25 C 40 result saving more than 27%.

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Portable reverse osmosis water filtration system with improved efficiency and reduced filter replacement. The system recycles concentrate fluid to increase permeate yield and minimize filter replacement. It has a mixing chamber with an adaptor and regulator, a feed pump, a boost pump, an energy recovery device, and a membrane apparatus with a concentrate chamber and permeate chamber. Concentrate is recycled to the mixing chamber via the regulator, and high-pressure concentrate goes to the energy recovery device. This allows more permeate to be extracted before replacing filters.

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Retrofitting a single-stage reverse osmosis (RO) system to a multi-stage RO system with higher recovery without replacing major components like high-pressure pumps (HPP) and energy recovery devices (ERDs). The retrofit involves adding a second RO stage and using turbochargers, an isobaric chamber, and a multistage pump to recover energy. The turbochargers replace the interstage pumps between stages. The isobaric chamber reduces feed pressure for the second stage. The multistage pump increases feed pressure for the first stage. This allows higher recovery without significant capital cost and maintenance compared to replacing the HPP and ERDs.

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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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A seawater-fed reverse-osmosis desalination plant that uses a watertight tank inside the barge or monopile to house the reverse-osmosis tubes. The tank is filled with water/fluid that is circulated to cool the tubes and transfer heat to an exterior seawater radiator. This allows close tube spacing without overheating issues. The seawater intake, pumps, reverse-osmosis membranes, and brine discharge are all contained inside the barge/monopile. The freshwater output is piped to shore using buried HDPE pipes. Grid power and internet connectivity are provided via HDD-installed cables. This allows remote operation of the plant without onsite personnel.

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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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With an increasingly more urbanised global population, surface water and groundwater resources are being/have become outpaced by growing demand. The oceans could address this pertinent scarcity issue, once their high-salinity content is removed. Water desalination thus be a crucial pathway towards addressing scarcity. However, conventional known to highly energy-intensive, with limited scalability potentially significant negative environmental impacts. Multi-criteria Decision Making (MCDM) presents novel approach sustainable based on sustainability-related criteria. Fuzzy Analytical Hierarchy Process (FAHP) was implemented determine the most optimal small-scale, modularised, remote reverse osmosis (RO) plant configurations. Twelve configurations were assessed, four capacities (50, 100, 150, 200 m3/day) three diesel-to-solar photovoltaic energy (1000%, 7525%, 6040%). hybridised generally ranked higher, particularly when less reliant diesel, at small(er) capacities, in terms of criteria: sustainability, overall efficiency, standalone potential while maintaining competitive cos... Read More

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Hollow fiber membrane module for improving overall treatment efficiency of reverse osmosis systems. The module has a pressure vessel containing a series of hollow fiber membrane elements. The elements are connected together using a connector. By connecting the elements in series instead of feeding the concentrated feed to later stages, all elements receive the unconcentrated feed, maximizing water production. This improves overall treatment efficiency compared to feeding concentrated feed to later stages.

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This study explores the application and robustness of an adaptive optimal control (AOC) strategy to optimize operation membrane filtration systems. The proposed is based on a constant flux model where fouling primarily due cake layer formation. algorithm dynamically finds ratio between (F) backwash (BW) time in response system disturbances, thereby adapting operational state order its performance terms energy consumption. was successfully applied both microfiltration (MF) ultrafiltration (UF) systems quantitatively demonstrated effectiveness reducing consumption controlling fouling. It proved robust against uncertainties real-time adaptability even under varying realistic disturbance conditions. implementation this facilitated adaptation filtration/backwash (F/BW) dynamic disturbances. result underlines that behavior predominantly driven by fluctuations mixed liquor suspended solids (MLSSs). Compared conventional fixed-time modes, AOC led significant savings, ranging from 7% 30%, lifespan extension, mainly through more efficient permeate pump usage.

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Reverse osmosis water treatment system and method that uses a two-stage filtration process to improve water quality. In the first stage, a high-flux reverse osmosis membrane removes impurities from the feed water. In the second stage, a lower-flux reverse osmosis membrane further filters the permeate from the first stage. The key difference is that the second-stage membrane has a lower flux per pressure unit than the first-stage membrane. This allows lowering the water quality degradation that can occur when using a membrane with lower rejection. By using a second-stage membrane with lower flux, the water quality can be improved compared to using a single high-flux membrane.

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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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This study investigates the potential for energy reduction in a full-scale Seawater Reverse Osmosis (SWRO) desalination plant through hybrid integration with Pressure Retarded (PRO). A pilot test using 60 m 2 PRO membrane kit helped determine key operating parameters, including draw solution (DS) pressure and resulting dilution fluxes. Subsequently, analysis was conducted 650 of area. The demonstrated up to 12.56% specific consumption under optimized conditions. Energy savings were found correlate positively lower feed pressures, higher brine availability, optimal rates, while being negatively impacted by losses high DS-to-FS flow ratios. confirms viability PRO-SWRO hybridization as method enhancing efficiency, highlights areas further optimization design hydraulic configuration.

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A system for efficiently and cost effectively removing impurities from fluids like water, oilfield wastewater, and produced water. The system uses a series of stages with devices like filtration, coagulation, reverse osmosis, thermal distillation, and recapture. The stages are arranged in a coordinated manner to progressively purify the fluid, remove specific components, and recapture energy. This allows efficient, customizable purification and recycling of wastewater while minimizing freshwater use. The stages can be containerized for portable, modular systems.

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Concentrating saline water is essential for zero liquid discharge (ZLD) of wastewater. However, prevailing membrane-based technologies, such as reverse osmosis (RO) and electrodialysis (ED), can hardly handle high concentration differences (C) in a single stage, where multi-stage operation needed, which increases the operational difficulties energy input. membrane capacitive deionization (MCDI) theoretically applicable to C. This study explored feasibility employing an MCDI brine concentrating proposed several regulating measures on electrode's porosity, electrical quantity charging-discharging, desorption conditions. Based determination salt fluxes, these were confirmed mitigate transfer across membrane, thereby facilitating transportation concentrating. To address mass imbalance between adsorbed desorbed, novel pre-charge strategy was designed, enabled successful continuous over 50 cycles. A difference 161 g/L NaCl achieved per highest reported result among RO, ED, studies. The rate 38.4 g/(m2h) with comparative consumption at RO ED. demonstrated that optional technology futu... 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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Integrated membrane filtration system for brine management in desalination plants to mitigate environmental impacts of high salinity discharge. The system uses a sequence of nanofiltration (NF) stages followed by reverse osmosis (RO) stages. The NF stages perform diafiltration to dilute and separate ions. The NF permeate feeds the RO stages. This allows optimizing ion fractionation and brine concentration while avoiding high salinity discharge.

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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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ABSTRACT This article presents a model-predictive controller (MPC) for the maximization of energy efficiency closed-circuit desalination reverse osmosis (CCRO) system. CCRO is process producing drinking water that based on cyclic operation with following two phases: (a) filtration and (b) drain. In this article, we test model predictive control optimal process. The most important features our approach are as follows: selection structure enables reliable forecasts phase (up to 3 h), an on-line calibration strategy ensures forecast reliability, (c) satisfaction equipment safety operational constraints selected setpoints. We challenge through deliberate introduction changes in unmeasured feed concentration applied constraints. Our results indicate frequent parameter updates critical maintain reliability MPC purposes. addition, illustrate identifiability not guaranteed variation flow rates necessary even though never operates steady state. Finally, can compute rate setpoints maximize while satisfying applicable

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Reverse osmosis system with optimized energy consumption for water treatment applications like desalination or wastewater reclamation. The system uses a chain of membrane units connected in sequence. Each membrane unit has an inlet, outlet, and concentrate outlet. The concentrate outlet of a unit feeds into the inlet of the next unit. The final unit's concentrate outlet connects to a hydraulic motor. This motor is connected to an electric generator. The generator can drive a pump upstream of a membrane unit to boost feed pressure. This recycles concentrate energy to drive the system. It eliminates wasteful high-pressure feed pumps. The motor can be variable frequency to adapt to changing conditions. Sensors on the axial piston machines monitor flow and pressure.

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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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Access to clean and potable water is a growing global concern, particularly in coastal arid regions where freshwater sources are scarce. Traditional desalination tech- niques, such as thermal distillation conventional reverse osmosis, rely heavily on fossil fuel-based energy sources, leading high operational costs significant environmental impacts, including greenhouse gas emissions. Additionally, these systems often require complex infrastructure, making them inaccessible remote off-grid communities. To address challenges, this research presents novel solar-powered machine that integrates Reverse Osmosis (RO) Ultraviolet (UV) purification technologies. The proposed system harnesses solar power high-pressure pumps, eliminating dependency non-renewable sources. RO unit effectively removes dissolved salts contaminants, while the UV stage ensures microbial disinfection, delivering high-quality drinking water. By utilizing renewable energy, significantly reduces minimizes carbon emissions, mak- ing it an environmentally sustainable economically viable solution. impact of extends enhancin... 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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Pure water production system with optimized water quality and energy efficiency when flow rate varies. The system has sensors to detect effective membrane pressure in the reverse osmosis section. Based on the sensor readings, it adjusts the number of parallel membranes treating the water. This allows maintaining stable membrane performance and water quality as flow rate changes, preventing deterioration. By dynamically matching membrane capacity to flow, it can save pump energy compared to fixed membrane systems.

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Automatic flow control for membrane water purification systems to optimize water production and membrane life while reducing waste. The method involves using a controller to dynamically adjust the diaphragm valve opening based on parameters like membrane performance, pump pressure, and water quality. This ensures the right balance of purified water flow and wastewater flow without manual intervention. The controller calculates an optimal ratio of wastewater to purified water to prevent excessive waste or membrane fouling. It also monitors factors like membrane temperature and pressure to detect fouling conditions and flush the membrane.

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A support system for optimizing water treatment processes using membrane filtration. The system uses machine learning to analyze water quality, filtration conditions, and membrane performance data to determine optimal permeation flux, cleaning frequencies, and cleaning conditions for the membrane filtration device. This provides recommendations to the water treatment operator on how to optimize their processes for better water treatment efficiency and membrane longevity.

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A system to adjust the flow rate of water coming out of a water purifier. It uses sensors to measure the inlet water temperature, pressure, and flow, and then adjusts the output pressure and/or flow of the water pump in the purifier. This allows correcting the water output to meet requirements for membranes like reverse osmosis. It solves the issue that existing water purifiers cannot adjust pump performance to match membrane needs. The system can also have buttons to change flow rates.

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Operating a water filtration system using a membrane module to identify clogged areas and clean them efficiently. The method involves monitoring pressure drops during filtration, backwashing, and water discharge. By comparing changes in these resistance values, it can determine if clogging is worse in certain areas. If so, it performs targeted cleaning like air washing, longer discharge time, or pressurized discharge. The idea is to proactively identify and address localized fouling without wasting water by blindly cleaning the whole module.

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Monitoring and optimizing the performance of membrane filters in filtration systems by continuously measuring the flow rate of permeate fluid and comparing it to a predefined flux rate. If the measured flux falls below the threshold, the system switches to a flux tolerant mode that allows higher fouling and lower filtration efficiency. This prevents unnecessary filter replacements when flux degradation is minor. The system also determines a normalized water permeability value based on the flux measurements to further assess filter health.

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A reverse osmosis water purification system with dynamic parameter adjustment to improve efficiency and stability compared to fixed settings. The system uses a control unit to monitor the operating conditions of the reverse osmosis device and adjust parameters like pump speeds, feedwater flow, and flushing frequency based on real-time data. This allows optimizing performance as components wear and conditions change over time. The control unit also provides warnings and alarms based on critical parameters like water levels.

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Reverse osmosis system with adjustable drain flow control based on feed water TDS. A self-regulating valve restricts concentrate flow to the drain in response to the feed water TDS level. A TDS sensor measures the concentration before the RO filter. The valve receives TDS signals and adjusts the drain flow accordingly. This allows optimized drain flow for varying feed water quality.

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A reverse osmosis water filtration system that automatically regulates the flow of concentrated wastewater based on the incoming raw water TDS level. The system has an adjustable valve that controls the flow of wastewater to drain. A TDS sensor measures the incoming raw water TDS and sends a signal to the valve. The valve adjusts the wastewater flow based on the TDS level to optimize membrane performance and extend membrane life for varying raw water qualities.

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Stable and energy-saving reverse osmosis system that adjusts recovery rate based on feed water quality to improve system stability and efficiency. The system has a control system that monitors feed water quality and adjusts the recovery rate of the reverse osmosis membrane group to maintain target concentrations in the permeate and concentrated streams. This prevents scaling, fouling, or waste due to fluctuating feed water quality. The control system uses sensors like conductivity, hardness, and SiO2 meters to measure feed water quality.

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A dynamic control system for reverse osmosis membrane fouling based on real-time monitoring of operating conditions. The system uses sensors on the inlet and outlet pipes of each membrane group to monitor parameters like pressure, conductivity, and flow rate. These signals are fed back to a control system to determine the best cleaning time for each membrane based on flux and transmembrane pressure differences. This allows targeted cleaning of fouled membranes instead of full system shutdowns.

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A method and device for maintaining constant water flow rate from a water purifier like a reverse osmosis system. It involves monitoring the inlet temperature and flow of the reverse osmosis filter element, and then controlling a heater and pump to maintain the inlet conditions within a range. This ensures a consistent outlet flow rate from the filter element.

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Optimizing reverse osmosis water treatment systems for higher recovery rates and longer operating cycles by using parallel connected membrane sections and valves to dynamically switch between single-stage and two-stage operation based on performance metrics like flow, pressure, and salt rejection. This allows flexible configuration to maintain optimal system efficiency and prevent fouling.

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An apparatus and method for controlling a reverse osmosis seawater desalination plant to optimize chemical dosing during pretreatment without impacting downstream filtration performance. The method involves monitoring turbidity, iron, and pressure increases in the ultrafiltration and reverse osmosis stages. If turbidity exceeds a threshold, chemical dosing is adjusted to lower it. If ultrafiltration or reverse osmosis pressure increases exceed limits, chemical dosing is adjusted to prevent excessive pressure rises. This coordinated chemical dosing optimization ensures downstream filtration performance while maintaining upstream turbidity control.

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A control system for a water purifier that regularly drains the high concentration water on both sides of the reverse osmosis membrane to improve purification efficiency. The system has a control module connected to the water purification module. When the pure water outlet stops, the control module opens valves to communicate the clean water, reverse osmosis filter, and waste water flow paths. When the pure water outlet is closed for a period, it opens valves to communicate the clean water, reverse osmosis filter, stale water, and waste water flow paths. This regularly drains the high concentration water on both sides of the membrane to prevent fouling and improve purification.

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Automatic feedback control system for reverse osmosis water filtration that maintains desired flow rates and water quality. The system uses iterative feedback loops to adjust feed water and concentrate water flow rates based on measured permeate flow rate and solute concentration. This continuously optimizes filtration efficiency and purity by compensating for factors like membrane type, feed water quality, and temperature.

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Monitoring the operation of a reverse osmosis membrane treatment system to detect fouling and take appropriate action. The monitoring involves measuring the power consumption of the water supply pump and monitoring the power value. Fouling tendency is determined based on fluctuations in supply flow rate, pressure, and temperature. If fouling is detected, measures like adding chemicals, changing pH, or temperature can be taken to suppress fouling.

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Automatic control system for combined reverse osmosis and electrical desalination devices to enable unattended operation without human intervention. The system uses level sensors on the fresh water tank and desalinated water tank to automatically adjust the frequency of the fresh water pump based on water level changes. This prevents low or high water levels in the tanks from affecting reverse osmosis and EDI devices. The system also has logic to start and stop both devices jointly, and to automatically restart them if stopped due to low water levels. The system provides stable operation and avoids frequent starts/stops without manual intervention.

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A reverse osmosis water treatment device with constant flow rate capability by using a rotating valve to regulate the water flow rate. The device has a base plate with a booster pump, display screen, flow detector, controller, and an energy recovery pump. A water valve pipe connects the pump to the reverse osmosis tank. A rotating motor drives a valve ball in the pipe to increase or decrease the water flow port and control the flow rate. This allows monitoring the flow rate, displaying it, and adjusting it using the motor to maintain a constant flow rate through the reverse osmosis process.

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A reverse osmosis water treatment system that uses automated controls to optimize performance and extend membrane life. The system has modules for dosing chemicals, monitoring water parameters, cleaning alarms, and filter replacement alarms. It uses a central control module to coordinate the functions and make decisions based on real-time parameter data. The system optimizes chemical dosing, prevents fouling, and schedules cleaning and filter replacements to maintain membrane performance.

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A self-regulating valve for a reverse osmosis system that adjusts the flow of wastewater based on the incoming water's total dissolved solids (TDS) concentration. The valve has a spool with varying bore widths. When the valve receives a TDS concentration signal, a motor rotates the spool to expose a wider bore section for higher TDS water, increasing wastewater flow. This compensates for reduced permeate flow through the RO membrane at high TDS. The valve also has a transmitter to send TDS signals. This allows on-site monitoring and adjustment of wastewater flow based on incoming water quality.

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Retrofit module for automating manual reverse osmosis systems used in the maple syrup industry. The module attaches to existing systems and has a controller with sensors to monitor parameters like pressure, flow, and brix levels. The controller compares the readings to thresholds and sends control signals to adjust components like valves and pumps. It can also transmit data to a mobile device. The goal is to retrofit manual systems with automation to optimize performance and reduce maintenance compared to fully replacing them.

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A method to accurately predict membrane fouling in reverse osmosis systems over both short and long time scales. The method involves collecting process and water quality data during operation, normalizing factors like flow rate and salt removal to account for temperature and flow variations, generating prediction equations using the normalized factors, and using the equations to forecast fouling levels. This allows determining chemical cleaning and membrane replacement times based on normalized factors rather than raw data, which is more reliable since it excludes influences from changing conditions.

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Operating a membrane separation device to reduce operating costs while avoiding sudden transmembrane pressure spikes. The method involves setting the membrane device's permeate flow based on the previous inflow, and stopping the device when water levels in the tanks it's immersed in drop below a threshold. This prevents sudden pressure rises due to fouling by maintaining a consistent flow while allowing occasional cleaning. The water levels are monitored to determine when to halt filtration.

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Control system to reduce TDS in aged reverse osmosis membranes when a water purifier is idle. The system pumps out waste water from the membrane after 30 minutes of inactivity to prevent salt buildup between the feed and permeate chambers. It does this by opening a waste water valve and pump after timing out. This reduces TDS in the first few cups of water after restarting the purifier. The system has a waste water outlet, valve, pump, and timer.

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Reverse osmosis water purification system that prevents back pressure damage to the membrane by allowing controlled relief of pressure during flushing. The system uses a check valve in the concentrated water line that allows backflow when the reverse osmosis device is powered off. This allows the pressurized concentrated water to bleed into the production line and relieve pressure there. When the device is powered on, the check valve closes and the normal reverse osmosis process continues. This prevents back pressure from building up during flushing.

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