National Alliance for Water Innovation (NAWI)

Innovating for a water and energy secure future for the United States

Research

Inland brackish groundwater desalination has the potential to expand water supplies in water-scarce areas, but adoption is constrained by the high costs and environmental impacts of concentrate (brine) disposal. Brine valorization—selectively extracting marketable products from desalination brines—offers a pathway to offset disposal costs, reduce environmental impacts, and improve economic feasibility. The challenge is that market potential depends both on technical recoverability of constituents and the ability of local or regional markets to absorb them.

To combat this challenge, a team of NAWI researchers, led by Alison Fritz at the National Energy Technology Laboratory (NETL), along with Alexander Dudchenko (SLAC), Casey De Finnda (UC Davis), and Meagan Mauter (Stanford), focused on two objectives. First, to develop a geospatially resolved market assessment that identified existing and potential markets for bulk constituents by pairing brine composition and expected volumes with market data on building materials, fertilizer, road salts, and chemicals, including caustic soda and hydrochloric acid. Second, to conceptualize and develop process models for brackish groundwater treatment and valorization and perform an economic and life cycle assessment of the proposed treatment.

To achieve the first goal, the project team used the U.S. Geological Survey brackish water databases to quantify volume and composition of groundwater sources across the United States. By pairing this volume and composition data with regional market demand for building materials, fertilizers, road salts, and industrial chemicals, the team conducted mass balances to determine how much recovered material local markets could realistically absorb. Next, to model the performance and costs of these prospective systems, they used NAWI’s WaterTAP platform to construct a digital reference treatment train. They then built a superstructure optimization model capable of evaluating the costs of thousands of candidate process configurations for treatment and valorization.

The preliminary optimization results indicate that in most scenarios, byproduct valorization is not the economically optimal configuration. The costs of the extraction schemes can outweigh the low market value of the recovered commodities. However, for certain water chemistries it can be valuable. For example, in highly saline scenarios, generating sodium chloride for road salt and hydrochloric acid and sodium hydroxide yielded outcomes that reduced net water treatment costs. The project also learned through stakeholder engagement that adaptable technologies that allow valorization decisions to follow market trends can improve the economics in volatile product markets.

Read the project brief and check out the project poster to learn more. To learn more about WaterTAP, register for NAWI’s upcoming webinar.

Potable water reuse was not initially on Emily Clements’ radar when she entered the University of Notre Dame at 15 years old, but both the school and the field proved a perfect fit. Clements first majored in chemical engineering, then returned to Notre Dame for both her master’s and Ph.D., culminating with a dissertation on modeling the impact of stochastic water demands in premise plumbing.

Following a two-year post-doc modeling water reuse in Lake Mead with the Southern Nevada Water Authority, Clements now serves as Reuse Innovation Manager at Carollo Engineers, Inc., where she works on advanced treatment performance. “I’ve always loved the environment, being outside, and asking questions, and I think my current role fits right in there,” Clements said. “Especially since my childhood dream job of scooping ice cream wouldn’t be as fun now that I’m dairy-free.”

A key component of that role is public health modeling, including evaluating pathogen and indicator removal, studying membrane fouling behavior, assessing treatment reliability, and quantitative microbial risk assessments. Water treatment systems can be highly complex, varying depending on the source water quality, operational conditions, and seasons. Understanding how these systems behave is an important but challenging task, especially given the low-probability, high-consequence nature of public health risks.

Clements leverages machine learning and statistical modeling techniques to address these challenges. “Many systems generate large datasets, but integrating those data into predictive tools, machine learning models, and risk assessment frameworks remains a developing area,” she said. Advancing those tools, she said, requires a “stronger integration” across disciplines, including environmental engineering, microbiology, computational analysis, and policymaking.

That integrated approach has already been featured in two NAWI projects: “Data-driven Fault Detection and Process Control for Potable Reuse with Reverse Osmosis” (5.17) and “A Convergent Monitoring Platform for Dynamic Characterization of Reverse Osmosis Membrane Fouling and Demonstration of Innovative Control Strategies” (3.13).

Risk mitigation is particularly important for potable reuse, where local environments often have limited alternatives. “Scarcity, population growth, and climate-related stress are increasing pressure on existing water supplies,” she said. Data analysis and predictive modeling can help utilities optimize system performance and anticipate treatment decline, improving reliability. “Potable reuse has the potential to provide sustainable and resilient water resources, but strong scientific understanding of treatment performance and risk is essential.”

Scientific findings must then be applied to a patchwork regulatory landscape, where risk tolerances and policies vary significantly across state and local boundaries. Communication with policymakers is now a critical two-way street. Improved understanding of treatment performance and risk allows for more informed water reuse regulations, in turn creating a better environment for utilities to operate in.

“Developing science-based, adaptable, and consistent regulatory approaches will be important for advancing safe and reliable reuse practices while maintaining public trust,” Clements said. Ultimately, the benefits are significant for resource-strained communities. “Improving confidence in potable reuse systems and strengthening treatment reliability can help support long-term water security while protecting public health.”

In addition to her professional work, Clements supports the Clean Water Help initiative, an organization that provides water disinfection and filtration services in countries including Cambodia, Ghana, and Guatemala. She is an avid Brandon Sanderson reader and writes creatively. She also enjoys hiking with her dog Toast, discovering new cafes, and a good thrift store find.

Conventional scale mitigation methods—anti-scalant addition, ion-exchange resins, and solvent extraction—require significant chemical or thermal inputs, which complicate brine management. While electrodialysis (ED) can potentially separate mono- and divalent ions, current membranes lack the selectivity needed for effective scaling control.

This project, led by Jovan Kamcev at the University of Michigan with partners at Lawrence Berkeley National Laboratory and Veolia WTS, focuses on developing highly selective ion-exchange membranes to improve ED pretreatment for brackish water reverse osmosis (BWRO). The developed membranes could enable high-recovery BWRO processes that are chemical-free and energy-efficient, improving brackish water desalination sustainability and reducing concentrate management challenges.

These membranes were tested in bench-scale ED systems to determine their ability to reduce scaling potential in RO processes. Process modeling was employed to optimize operational parameters, including water recovery and energy consumption, for maximum efficiency.

Testing revealed that divalent-selective single-layer membranes achieved Ca²⁺/Na⁺ selectivity values of approximately 4 at low current densities, a performance level notably higher than that of commercial membranes. Monovalent-selective bilayer membranes exhibited extremely high Na⁺/Ca²⁺ selectivity across various brackish water chemistries; however, their ion transport fluxes were about an order of magnitude lower, reflecting the reduced limiting current density inherent to the design. Membranes featuring sulfonate and phosphate functional groups demonstrated the best Ca/Na separation factors under realistic brackish water compositions, indicating strong potential for practical scaling control.

Following bench-scale validation, the membranes will be scaled up for pilot plant demonstrations in collaboration with an industrial partner. A technoeconomic analysis will also be conducted to evaluate the commercial viability and overall feasibility of these pretreatment solutions.

The next phase will focus on conducting ED experiments using larger membrane stacks, with findings intended to calibrate the ED process model developed by WaterTAP. This progression marks a significant step toward bridging bench-scale insights with pilot-scale application readiness.

Access the project poster for more information.

From Self-Reflection to a Research Path

After completing her bachelor’s degree in Illinois Tech in Chicago and returning home to Malaysia, Nazia Aslam began thinking seriously about what she wanted for her future. Although she had always been interested in science, pursuing a PhD was not something she had previously considered or seen people around her do.

“I started asking myself what kind of life I truly wanted, not just what was available to me, but what I could build for myself,” Nazia said. “I realized that I wanted to do meaningful work, to challenge myself, and to create opportunities that didn’t yet exist in my world.”

That realization led her back to the United States, where she is now a fourth-year Chemical Engineering PhD student at the University of Connecticut. As the first person in her family to pursue this path, Nazia describes the decision as both difficult and transformative.

Process Intensification of Water-Treatment Systems

Today, her research bridges chemical engineering, machine learning, and water treatment systems. Her work focuses on developing interpretable and efficient models that can uncover governing physics and improve the design and operation of complex dynamic processes.

At the beginning of her PhD, Nazia worked on comparative studies involving physics-informed neural networks and symbolic regression to identify governing partial differential equations from sparse and noisy data. Her work was presented at venues including a Data-Driven Physical Simulations seminar at Lawrence Livermore National Laboratory, a CRUNCH group webinar at Brown University, and the 2023 INFORMS Annual Meeting.

She later contributed to two projects funded by the National Alliance for Water Innovation. One project focused on modeling and simulating high-concentration brine desalination systems using open-source Python-based tools including Pyomo, WaterTAP, and IDAES. Her work demonstrated how the incorporation of more accurate thermodynamic models, which improved predictions of thermodynamic properties, reduced the estimated specific energy consumption of thermal desalination systems by more than 17% compared to conventional methods.

Infographic showing a five-step workflow for improving thermal desalination efficiency using high-accuracy thermodynamic models and process optimization. Step 1 highlights improved thermodynamic property models that reduce uncertainty in energy consumption estimates. Step 2 shows system modeling and simulation of a solar-powered triple-effect distillation desalination system with an absorption heat pump, including a detailed process flow diagram. Step 3 focuses on process optimization using thermodynamic constraints, mass and energy balances, and decision variables such as temperatures, heat duties, and flow rates. Step 4 presents the impact, showing a greater than 17% reduction in specific energy consumption when using refined models compared to conventional models. Step 5 illustrates a continuous improvement cycle of defining targets, simulating, analyzing results, and refining models.
Workflow for advancing a separation system of high brine concentration through refined thermodynamics and process intensification. Illustration by Nazia Aslam.

Innovations in Water Treatment and Future Directions

Desalination plays an increasingly important role in addressing global water scarcity, but many processes are highly energy-intensive and involve complex brine chemistries that are difficult to model accurately. In addition to conducting the research, Nazia also developed reusable software packages and documentation that were made accessible to the broader research community through WaterTAP’s open-source GitHub repository.

More recently, she has been developing interpretable models for long-term membrane fouling prediction using ultrafiltration system data. Membrane fouling remains one of the largest operational challenges in membrane-based water treatment due to its dynamic and multifactorial nature. Nazia’s work aims to improve system management and reduce operational costs by creating models that can better predict fouling trends across operational cycles.

Her current research focus explores large language model-based approaches for discovering governing physics in complex systems.

Because her work spans multiple disciplines, adapting to the pace and breadth of the field has been one of the biggest challenges of her PhD journey.

“Coming from an experimental and industrial background, moving into work that involves coding, modeling, and artificial intelligence felt overwhelming at first,” she said. “I found myself learning new tools and ways of thinking while simultaneously tackling new research challenges.”

Despite these hurdles, she sees the interdisciplinary nature of the field as one of its most rewarding aspects. Her work has the potential to benefit researchers, engineers, industry professionals, and policymakers working to improve the efficiency and sustainability of water treatment systems.

Looking ahead, she hopes to continue pursuing research that addresses real-world challenges while also contributing to expanding educational opportunities in developing communities.

“I believe education empowers individuals to create better opportunities for themselves,” she said.

In addition to her research, Nazia recently became the programming director of the NAWI Next Generation Leadership Council, where she helps lead initiatives that connect students, researchers, and industry professionals through events such as technical webinars. After graduation, she hopes to pursue a research-focused role in either national laboratories or industry.

Nazia’s journey reflects both personal determination and a willingness to step into unfamiliar spaces. What began as a decision to challenge herself has evolved into a career dedicated to solving complex problems and building tools that can make a lasting impact.

Current reverse osmosis and nanofiltration membranes, which are often extremely delicate and thin, generally do not tolerate waters with suspended solids or high loadings of organics. Pretreatment is nearly always employed to reduce these contaminants which can foul or even abrade membranes. Current pretreatment approaches rely on decades-old technology, are expensive or chemically intensive, and can constitute a majority of the system footprint. They are also difficult to adapt for different treatment systems and typically struggle to entirely prevent fouling.

NAWI’s 5.22 project, “Printed Polyelectrolyte Complex (APEC) Membranes for Ultra-high Permeance Nanofiltration,” aims to create the first nanofiltration (NF) membranes for universal pretreatment. These NF membranes would streamline the pretreatment process to be more efficient across different types of treatment systems or water sources while simultaneously saving costs, energy, and treating more water with better output quality.

This project achieve this using a newly developed additive manufacturing process. This process, known as electrospray,  which uses high voltage to  induce fine, nano-scale sprays to deposit thin and defect-free layers of polymer electrolyte and produce multi-layered membranes with better control. This technique, called “electrospray additive manufacturing,” can form exceptionally thin (~10s of nanometers per layer or less) and defect-free films from any solution-processable polymer.

Electrospray is suited for forming amphiphilic polyelectrolyte complexes (APECs), which bring the positively and negatively charged polymers together to form a material that is both hydrophilic and hydrophobic. These specific properties of APECs create a stronger, adjustable material that better prevents fouling. By using numerous yet exceedingly thin bilayers, the goal of the research is to prevent membrane defects and make pretreatment more efficient, while creating NF membranes with the potential for 5-10 times higher permeance than commercial NF membranes made today.

NAWI has funded a number of pilot projects that are intended to demonstrate the scaling of new technologies from bench scale or laboratory prototypes to large—and often mobile—field-deployed systems on relevant waters at or near their source. One such pilot project, led by Purdue University, is looking at batch reverse osmosis (BRO).

BRO has been proposed as a more energy-efficient alternative to conventional reverse osmosis (RO), primarily due to the former’s ability to operate closer to the brine’s osmotic pressure during permeate production. In this work, David Warsinger and his team designed, constructed, and tested a pilot-scale conventional RO, closed-circuit RO (CCRO), double-acting reciprocating piston BRO, and bladder-based BRO configurations within the combined system. By using the same pilot system across all tests, the influence of variables such as feed water composition, membrane type, piping, and pump selection is minimized. The pilot system is fully operational and can automatically run using a LabView VI.

The system is designed to handle high-salinity water and is comprised of several components (e.g., check valves, 3-way valves, and 2-way valves). A 5-micron cartridge filter was installed to protect the RO membrane and remove small particles. A feed tank provides the necessary feed water to the system, while separate tanks are used to store the brine and permeate flows. Additionally, different sensors and transducers are used to monitor the main operational variables in the system such as flow rates, pressure, conductivity, pH and temperature.

Experimental results obtained with the pilot system were used to parameterize and validate a predictive model. This model discretizes the membrane module’s feed channel in both the axial and transverse directions to capture the effects of concentration polarization and pressure losses on system performance. By simulating the pressure evolution over time, this model can calculate the system’s specific energy consumption (SEC).

The system has operated continuously for over 900 hours, with seamless switching between configurations. To date, more than 800 million data points have been collected.

The pilot has been operated with different feed salinities (brackish and seawater) and a range of water fluxes and recovery ratios. Preliminary results support previous predictions, showing that CCRO and Batch RO outperform Conventional RO in energy efficiency and achievable recovery.

The results also show that the selected performance indicators are being met with minimal to no leaks observed at operating pressures of up to 1000 psi. Both SEC and the recovery ratio remained within 5% of initial values throughout testing, even after consecutive operating cycles.

For more information, access the project research brief.

A recent article in the Chemical Engineering Journal details a study of how electromagnetic field (EMF) technology can reduce mineral scaling in water treatment systems and why results vary across applications. Mineral deposits such as calcium carbonate, gypsum, and silica—often called scale—can coat pipes, heat exchangers, and membranes, reducing efficiency, blocking flow, and increasing maintenance and cleaning demands. Conventional chemical antiscalants can be effective but raise concerns about handling, cost, waste, and the long-term complexity of continuous dosing and system monitoring.

The study by NAWI researchers Pei Xu, Xuewei Du, Huiyao Wang, Yanxing Wang, Fangjun Shu, Lawrence  Anovitz, Ke Yuan, and others, shows that EMF treatment can reduce scaling by influencing both minerals suspended in water and crystals growing on surfaces. Bench tests on heat-exchanger and membrane-distillation systems showed fouling dropped by 15–79%, while pilot and field studies in reverse osmosis systems saw scaling fall by 40–45%. EMF effectiveness is highly dependent on water chemistry, system configuration, and operating conditions, which helps explain why some systems see strong results and others see less benefit.

EMF works through two main mechanisms: homogeneous nucleation in the bulk solution and heterogeneous crystal growth on surfaces. The study also explores how EMF strength, frequency, waveform, and flow velocity affect outcomes. By combining pilot-scale experiments and modeling simulations, the study shows how adjusting these parameters can optimize performance for different water treatment setups.

EMF systems operate without chemicals, produce no secondary waste, and require minimal energy. Case studies in cooling towers and reverse osmosis systems show reduced cleaning downtime, energy savings, and longer water reuse before blowdown or discharge. The study notes that hybrid approaches, combining EMF with low-dose antiscalants, may further improve reliability and cost-effectiveness, but systematic testing is needed to confirm performance and compatibility.

The authors conclude that EMF shows real potential for chemical-free scale control, but its effectiveness depends on a clear understanding of how it affects mineral behavior in water and how deposits attach to surfaces. Although long-term, full-scale validation and standardized testing protocols are still needed, the study sheds light on the mechanisms and operational factors that drive performance. By clarifying how EMF interacts with different water chemistries and system conditions, the study highlights the circumstances under which EMF could provide a reliable, cost-effective approach to reducing mineral scaling in a range of water systems.

The National Alliance for Water Innovation (NAWI), which is led by the Department of Energy’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab), has been extended for five more years with $75 million in funding from DOE. NAWI will continue its contributions to helping decarbonize the water and wastewater sectors through investments in technologies that enhance the efficient use of energy for water use, treatment, and distribution.  

“Water and energy are interdependent—water is used to produce nearly every major energy source, and energy is critical to transporting and treating water,” said Jeff Marootian, Principal Deputy Assistant Secretary in the Office of Energy Efficiency and Renewable Energy. “The deep connection between these two resources demands an integrated approach that considers the challenges and opportunities inherent to both sectors. The Department of Energy is proud to be leading the nation’s efforts to decarbonize the water economy, while ensuring a secure water future for communities nationwide.”

Over the next five years, NAWI is shifting its focus to include regional water systems planning – and will partner with water planners at the state and regional level to develop and use new tools for water supply forecasting, water demand forecasting, and water portfolio optimization. NAWI will also spearhead water resilience pilot projects and implement regional water system workshops. These new directions will enable NAWI to continue to accelerate breakthroughs towards a circular water economy, where water is treated to fit-for-purpose standards and reused locally, rather than transporting freshwater long distances. 

“Desalination and innovative water treatment technologies hold great promise for helping us meet our planet’s growing demand for one of our most precious resources: water,” says Mike Witherell, Director of Lawrence Berkeley National Laboratory. “The Department of Energy’s renewed support for NAWI enables the continuation of cutting-edge research and development which is needed to not only treat unconventional sources of water for re-use but to lower their cost and energy use.” 

Over the past five years, NAWI has supported a robust research portfolio with 60 original and innovative research and development projects that span analysis for water-energy grid integration to the development of algorithms, models, and adaptive process controls for resilient operations. In addition, NAWI has supported the implementation of 11 pilot projects that have begun work demonstrating some of these innovative technologies in real-world environments. NAWI has also developed the NAWI Alliance with over 1,670 members, and partnered with over 420 leading industry, academic, and government stakeholders. NAWI has also developed a suite of knowledge products, including a master roadmap and series of industry-specific roadmaps to prioritize the highest impact technology options, and its 60 projects support those priorities. To date, NAWI researchers have published more than 100 articles in high-impact research journals. 

“Our research program remains steadfast in its commitment to reducing the price, energy cost, and greenhouse gas emissions of new water technologies,” said Peter Fiske, Executive Director of NAWI. “Our work also bridges cutting-edge research with real people and places, such as producing secure, reliable, and affordable water for communities that are most in need.”

Throughout the next five years, NAWI will remain committed to the principles of Inclusion, Diversity, Equity, and Accountability (IDEA). NAWI’s pilot projects will continue to treat unconventional water sources to provide usable water in real-world environments. Some of the pilot projects will partner directly with communities and groups that have historically been underserved by existing water supplies. Each project will also generate a range of data sets usable by other researchers seeking to advance the field of data analysis and automation, and fault detection in water treatment systems.

NAWI’s plan for the next five years aligns well with the California’s Water Supply Strategy (WSS) – Adapting to a Hotter Drier Future, which outlines a strategy and priority actions to adapt and protect water supplies from the effects of rising temperatures and drier conditions due to climate change. The California Water Plan is the State’s strategic plan for sustainably and equitably managing and developing water resources for current and future generations. Key actions include enhancing water conservation efforts and accelerating innovation related to water treatment, reuse, and desalination.

“Securing a more resilient water future for California means investing and building meaningful relationships with key partners like NAWI. This collaboration will help drive innovation for new, affordable water supplies for a more water resilient future for generations to come,” said California Department of Water Resources Director Karla Nemith.

The next phase of NAWI also aligns with the California Water Plan Update 2023 (Update 2023), which champions climate resilience throughout various regions and water sectors by offering a comprehensive approach. This approach includes a statewide vision, well-defined goals, a watershed planning framework, a versatile toolkit, and a dashboard for tracking progress indicators.

“Regional water systems planning is critical to addressing questions of where, when, and how non-traditional source waters are most effectively deployed for enhanced U.S. water security,” said Meagan Mauter, Research Director of NAWI. “Regional systems models also help to establish the value of desalination technology innovation, linking the R&D NAWI performs on new nanoscale materials or intensified processes to dollars saved and carbon saved. The balance of our program will continue to advance device and treatment research investments from the first 5 years of NAWI, including a focus on cost effective, energy efficient desalination technologies and advanced data, modeling, and control systems for complete treatment trains.”

The NAWI program will significantly contribute to the implementation of the updated water plan, demonstrating novel methods for water reuse at the community and premise scale, along with further advancing key reuse technologies such as desalination and fit-for-purpose treatment. NAWI will support California and the nation to in their efforts to keep pace with the impacts of climate change, facilitating smarter and swifter updates to its water systems.

“The next five years present an invaluable opportunity to deliver impact aligned with NAWI’s pipe parity metrics and further the country towards net-zero emissions by 2050,” said Fiske.

NAWI will continue to be supported by the DOE Office of Energy Efficiency & Renewable Energy’s Industrial Efficiency and Decarbonization Office. 

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NAWI is a research program and public-private partnership supported by the United States Department of Energy in partnership with the California Department of Water Resources and the California State Water Resources Control Board. NAWI brings together a world-class team of industry and academic partners to examine the critical technical barriers and research needed to radically lower the cost and energy of desalination. NAWI is led by DOE’s Lawrence Berkeley National Laboratory in collaboration with the National Renewable Energy Laboratory, Oak Ridge National Laboratory, National Energy Technology Laboratory, and the SLAC National Accelerator Laboratory and funded by the Office of Energy Efficiency and Renewable Energy’s Industrial Efficiency and Decarbonization Office and Water Power Technologies Office.

Additional information:

NAWI Research Director Meagan Mauter and NAWI Deputy Topic Area Lead for Materials and Manufacturing Jeff McCutcheon authored an article for Science that highlights why materials discovery alone has not translated into lower-cost water treatment. The publication emphasizes that the enduring dominance of traditional reverse osmosis membranes reveals a broader need within the water treatment community to reassess the innovation pipeline for membranes for desalination and water treatment. Read the article.

The U.S. Department of Energy (DOE) and the National Alliance for Water Innovation (NAWI), in collaboration with the California Department of Water Resources, today announced the selection of 11 projects for negotiation that will pilot breakthrough technologies and systems that will allow for more reliable and affordable freshwater supplies for the United States. The projects will also contribute to the decarbonization of the water and wastewater sectors through investments in technologies that enhance the efficient use of energy in the use, treatment, and distribution of water.

The selected pilot projects will process non-traditional source waters from a range of locations and produce water in real-world environments. In some cases, projects will partner directly with communities and groups that have historically been underserved by existing water supplies. The research will help to bolster a circular water economy by supporting water reuse and valorizing constituents we currently consider to be waste. Each project will also generate a range of data sets usable by other researchers seeking to advance the field of data analysis and automation, and fault detection in water treatment systems.

The collaborative project teams of industry, academic, national laboratory, and other stakeholders will deliver impact aligned with NAWI’s pipe parity metrics. Pipe parity is defined as technology solutions for treating and reusing nontraditional water sources that are competitive with conventional water sources for specific end use applications.

These pilot systems will directly address the highest priority research needs and technical knowledge gaps outlined in the NAWI Roadmap Publication Series, which was published in 2021.

The selected projects include:

(Listed in no particular order)

  • Concentrate Treatment and Chemical Production Using Innovative Electrodialysis Processes for Near Zero-Waste Discharge

Desalination technologies typically extract a fraction of pure water and leave behind a salty residual liquid called brine or concentrate that is expensive and difficult to dispose of at inland desalination facilities. This project is focused on the design and build of a novel process to further concentrate the brine using electrodialysis, producing more water and transforming the dissolved salts into valuable industrial chemicals. The pilot system will be fielded at the Kay Bailey Hutcheson Desalination Plant in El Paso, Texas.

Partners: New Mexico State University (lead); Veolia Water Technologies and Solutions, Inc.

  • Switchable Solvent ZLD Process for Solving the Inland Desalination Brine Problem

Desalinating and reusing municipal, industrial and agricultural wastewater is an attractive approach for improving the reliability and resilience of water resources. But the presence of dissolved minerals that can plug RO membranes and modules (a process called scaling) limits the amount of water that can be recovered using membrane processes such as RO. This project aims to integrate a novel, high-efficiency process for removing scale-forming ions from brine concentrates, enabling much higher amounts of water recovery and smaller volumes of waste brine. The mobile testbed will demonstrate high-recovery desalination at five sites in California.

Partners: Global Water Innovations, Inc. (lead); Trevi Systems, Inc.

  • Mobile Test Bed for Marginal Water Filtration

Water pre-treatment (before desalination) remains a critical process step for maximizing water production and lowering desalination cost. Current pretreatment technologies are large, slow, and multi-step, making them suitable for large desalination projects but clumsy and less effective for small-scale systems. This project will integrate a novel high-performance nanofiltration membrane system as pretreatment alongside two variants of electrocoagulation as a high-efficiency, all-electric pretreatment strategy. The mobile testbed developed by this team will travel to several sites around Albuquerque, New Mexico, evaluating high-efficiency desalination of different non-traditional water sources.

Partners: Garver USA (lead); City of Rio Rancho, New Mexico; the University of California, Los Angeles; NX Filtration, University of Colorado-Boulder; WaterTectonics, Inc; Rockwell Automation; Powel Water

  • Salt-Free Electrodialysis Metathesis (EDM) for High-Recovery Concentrate Management

Electrodialysis Metathesis (EDM) is a desalination process that uses specialized membranes and chemistry to produce fresh water while transforming the residual brine into two streams – a calcium-rich solution and a sulfate-rich solution. These two streams can be further refined into valuable industrial chemicals, producing a secondary revenue stream from desalination – and reducing the volume of waste brine. Until now, EDM has required the addition of sodium chloride (NaCl) to supply required ions for these solutions. In this project, a new ion-selective membrane technology will be utilized that will eliminate the need for additional NaCl and may lower the energy requirements of traditional EDM by as much as 50%. The system will be tested at the U.S. Bureau of Reclamation’s Brackish Groundwater National Desalination Research Facility (BGNDRF) in Alamogordo, New Mexico.

Partners: University of Texas, El Paso; New Mexico State University

  • UHP-CCRO with Virtual Curtain to Achieve Minimal Liquid Discharge

Softening is the process of removing certain ions from water that otherwise precipitate during the desalination process, limiting the amount of water that can be recovered from inland brackish water sources using RO. This project proposes to use a novel softening technology to selectively remove these scale-forming ions by forcing the precipitation in the form of hydrotalcite – a mineral that is made from these ions – that could be used as a soil amendment or as an additive for concrete.

Partners: Jacobs Engineering (lead); New Mexico State University; Commonwealth Scientific and Industrial Research Organisation; DuPont

  • Mobile Demonstration DPR: Comparison of RO and non-RO DPR for aerobic and anaerobic effluents

Municipal wastewater can be reprocessed into drinking quality water. Reverse osmosis (RO) has traditionally been a final treatment step that can provide the high purity required to satisfy drinking water quality regulations, but RO generates a brine waste stream and drives up the cost and energy required for direct potable reuse (DPR). This project will perform a side-by-side demonstration at Silicon Valley Clean Water’s treatment plant in Redwood City, California, of both an RO-based treatment train and a novel treatment train that achieves nearly the same purity without using RO. The team will also investigate how different types of wastewater treatment technologies produce effluents that are either easier or harder to transform into drinking quality water.

Partners: Colorado School of Mines (lead); Stanford University; University of Colorado, Boulder

  • Piloting an Electrical, Modular, and Distributed ZLD Arsenic-Removal Technology

Arsenic is a pervasive, naturally occurring carcinogenic contaminant in groundwater. Thousands of wells in California and around the world have arsenic levels that exceed safe levels, forcing communities to install expensive and hard-to-operate treatment systems or shutter their local wells and travel miles to fill water jugs for home use. This project will demonstrate a new simple, reliable and highly automated electrochemical process that uses iron and electrical current to safely remove arsenic in well water. The team will partner with the community of Allensworth, California, a rural community whose residents must drive miles to pay for retail water from a kiosk.

Partners: University of California, Berkeley (lead); Allensworth Progressive Association

  • Reciprocating Piston Batch Reverse Osmosis: Pushing the limits of efficiency and fouling resistance

Conventional reverse osmosis utilizes high pressure pumps to continuously supply pressure into RO modules and generate fresh water. This steady-state process can result in the gradual build-up of organic and inorganic precipitates on membrane surfaces (known as fouling), which reduces water production and requires frequent cleaning. This project will demonstrate a novel batch-mode process whereby RO modules are pressurized using a piston-based pump and fresh water is produced in a non-continuous process. This approach to reverse osmosis not only uses less energy but may also greatly reduce the rate of fouling of membrane surfaces.

Partners: Purdue University (lead); Colorado School of Mines; Oak Ridge National Laboratory

  • Integrated Counter-Flow Reverse Osmosis Treatment for High-Salinity Produced Water

High salinity produced water is predominant in U.S. oilfields. Reverse osmosis (RO) has been used to desalinate low-salinity produced water, but has a salinity limit below that of most U.S. produced waters. This project will field a novel advancement that uses commercial RO membranes and infrastructure, and counterflow RO (CFRO) in order to enable treatment of high salinity water by managing the osmotic pressure differential across the membranes of sequential stages in a counter-flow arrangement.

Partners: Aris Water (lead); New Mexico State University; Texas Agricultural and Mechanical University; Stanford Linear Accelerator Center; Garver, OLISoft, Inc.

  • Field Pilot Testing of Electrically Conductive Reverse Osmosis (ECRO) Membranes for High Mineral Content Brackish Groundwater Desalination

Unconventional and difficult-to-treat water resources, such as brackish groundwater, have complex chemistries, and treating them to freshwater levels requires complex processes consisting of multiple stages of pre-treatment followed by membrane desalination, making them costly and difficult to operate which limit their widespread application and adoption by society and various industries. Both ECNF and ECRO use combinations of applied electrical fields and in situ electrochemical generation to actively resist membrane fouling – the deposition of particles onto membrane surfaces that causes pore clogging and diminished performance over time. The project will operate the pilot system as two parallel trains to evaluate the head-to-head performance of ECRO compared with conventional RO at Sand City, California.

Partners: Pacific Water Solutions, Inc.

  • A Convergent Monitoring Platform for Dynamic Characterization of Reverse Osmosis Membrane Fouling and Demonstration of Innovative Control Strategies

Membrane fouling and scaling is a pervasive and costly aspect of many membrane-based water treatment systems. This project will demonstrate and validate an unprecedented sensing/time series monitoring system at Orange County Water District for the dynamic characterization of reverse osmosis (RO) biofouling, mineral scaling, and organic fouling. The data obtained from this system will be combined with pilot and full-scale RO performance data to train next-generation Machine Learning (ML) and Artificial Intelligence (AI) models to better forecast and mitigate fouling and scaling. This project will also evaluate novel sensor technologies and a new commercial membrane technology that can resist the application of oxidizing cleaning chemicals.

Partners: Rice University (lead); University of Texas, Austin; University of Tennessee, Knoxville; Oak Ridge National Laboratory; Orange County Water District; Noria Water Technologies, Inc., NALA Membranes, Inc.; Carollo Engineers

NAWI is a public-private partnership that brings together a world-class team of industry and academic partners to examine the critical technical barriers and research needed to radically lower the cost and energy of desalination. NAWI is led by DOE’s Lawrence Berkeley National Laboratory in collaboration with National Energy Technology Laboratory, National Renewable Energy Laboratory, and Oak Ridge National Laboratory, and is funded by the Office of Energy Efficiency and Renewable Energy’s Industrial Efficiency and Decarbonization Office.

The U.S. Department of Energy (DOE) and the National Alliance for Water Innovation (NAWI) today announced the selection of seven projects that will advance breakthrough technologies for reliable and affordable freshwater supplies for the United States. The selected projects will conduct early-stage applied research on desalination and treatment of nontraditional water sources for beneficial end uses. The research will help to bolster a circular water economy by supporting water reuse and valorizing constituents we currently consider to be waste.

The collaborative project teams of industry, academic, national laboratory, and other stakeholders will deliver impact aligned with NAWI’s pipe parity metrics. Pipe parity is defined as technology solutions for treating and reusing nontraditional water sources that are competitive with conventional water sources for specific end use applications.

The research will directly address the highest priority research needs and technical knowledge gaps outlined in the NAWI Roadmap Publication Series, which was published in 2021. The projects focus on addressing challenges related to either autonomous water or precision separation. The autonomous water challenge area aims to develop sensor networks and adaptive process control for improved water desalination treatment systems. The precision separation challenge area aims to develop flexible platform technologies that remove (and/or recover) target compounds from one or more priority classes of contaminants and from specific water end use sectors.

The selected projects include:

(Listed in no particular order)

  • Energy-Efficient Selective Removal of Metal Ions from Mining Influenced Waters Using H-Bonded Organic-Inorganic Frameworks

The H-Bonded Organic-Inorganic Frameworks technology will bring tremendous value into the treatment of nonconventional waters with reduced energy consumption, system complexity, and waste management costs while providing unmatched brine valorization and profit recovery. The precision separation and recovery of metals in acid mine drainage (AMD) waters may also expand the availability of critical materials and help alleviate dependency on metal supply chains for the U.S.

Partners: Rio Tinto Services Inc. (lead), Lawrence Berkeley National Laboratory, University of Oklahoma, California Department of Water Resources (funding partner)

This project will use machine learning and artificial intelligence to reduce energy and chemical use, improve operational support, increase treatment system uptime, and improve confidence in purified water quality.

Partners: Carollo Engineers, Inc. (lead), Yokogawa Corporation of America, National Water Research Institute, U.S. Military Academy West Point, tntAnalysis, Las Vegas Municipal Water District, Metropolitan Water District of Southern California, West Basin Municipal Water District, Orange County Water District, Baylor University, California Department of Water Resources (funding partner)

This project will generate a technology that enables the selective removal and recovery of metals/oxyanions from water, enabling the use of a non-traditional water source, significantly reducing the cost and energy of treatment, and valorizing compounds that would typically be considered waste.

Partners: University of California, Berkeley (lead), Greeley and Hansen LLC, NTS Innovations Inc., California Department of Water Resources (funding partner)

Copper recovery will help to achieve pipe parity with conventional treatment of mining process waters and/or reuse at copper mines and refineries while simultaneously improving environmental sustainability. The project will also provide platform technology that can be used to develop additional ion-selective cation exchange membranes, targeting other ionic contaminants of interest, such as lead and cadmium.

Partners: Rice University (lead), The University of Texas El Paso, Magna Imperio Systems Corp.

This project will overcome the persisting inefficiencies in the current state-of-the art boron removal strategies. The research will also provide a demonstration of an effective method for electrosorption of weak acid/base species and selective removal of trace contaminants.

Partners: Yale University (lead), University of Michigan, Magna Imperio Systems Corp.

Selective electrosorption technologies for the separation and concentration of charged nutrients could enable a sustainable water treatment paradigm, particularly for small communities that struggle to operate centralized facilities and highly sensitive biological removal systems. 

Partners: University of Illinois at Urbana-Champaign (lead), Lawrence Livermore National Laboratory, Oak Ridge National Laboratory, Voltea Inc.

This project will overcome technical limitations of existing per- and polyfluoroalkyl substances (PFAS) destruction technologies by improving selectivity for PFAS destruction, minimizing toxic byproduct formation, and limiting short-chain PFAS formation.

Partners: University of Illinois Chicago (lead), Purdue University, Argonne National Laboratory, M. Davis & Sons Inc., Trimeric Corporation, CDM Federal Programs Corporation, Orange County Water District

NAWI is a public-private partnership that brings together a world-class team of industry and academic partners to examine the critical technical barriers and research needed to radically lower the cost and energy of desalination. NAWI is led by DOE’s Lawrence Berkeley National Laboratory in collaboration with National Energy Technology Laboratory, National Renewable Energy Laboratory, and Oak Ridge National Laboratory, and is funded by the Office of Energy Efficiency and Renewable Energy’s Industrial Efficiency and Decarbonization Office.