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Results for “Electrodialysis Reversal Treatment”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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8 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Topical Report on Water Balance Model Development and Initial Application

This topical report summarizes results from developing a generic dynamic water balance tool which can be used by coal-fired power plant operators to evaluate FGD water management strategies. EPRI is using a statistical software model created on the GoldSim platform and data from coal-fired energy plants to determine the fraction of power plant water needs that can be satisfied by electrodialysis reversal treatment and, correspondingly, the discharge volume and/or byproducts that still need to be managed. The generic model is designed to accept a number of easily obtainable process variables and generate probabilities of resultant water characteristics. The model is also constructed as a universal process flow; one that can be adjusted to accommodate most major components of an FGD blowdown handling system. The generic model is dynamic and utilizes user-inputted operational variation in water quality and quantity to best provide a probabilistic representation of potential performance outcomes. In order to account for complexities of water composition and treatment, a separate chemical modeling software is used to evaluate water chemistry and unit operation performance. The thermodynamic modeling software, OLI Studio, is employed to convert ion data from laboratory analyses into balanced molecular concentrations that are classified as dissolved and suspended solids. The dynamic water model is designed to import a total of 11 species commonly found in FGD blowdown water as molecular concentrations.Water management unit operations are used in the model and categorized by either physical unit operation blocks or chemical unit operations blocks. As the name implies, the physical water treatment blocks are unit operations that are exclusively physical changes to the system (e.g., separations and volume changes). The chemical water treatment blocks are unit operations where chemical changes occur and require the use of OLI Studio to characterize subsequent streams. Water and material balances from three unique coal-fired power plants were obtained and preliminary modeling on the dynamic water balance tool was performed using the extracted data from these power plants. These three power plants were chosen due to their unique configurations and water profiles that represented a variety of operational changes. Results from using the dynamic tool with the three plant configurations are presented and discussed in the context of the existing tool and planned future capabilities.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2022

A Review: Flow Electrode Capacitive Deionization for Improved Electrochemical Water Desalination

In many places of the world people have continued to suffer from major droughts and water shortages. With climate change climbing in intensity, these dry conditions will only worsen. With much of the world’s water in the ocean, both saltwater and brackish water have been identified as key water sources. Currently, there are several technologies available for water desalination and treatment such as reverse osmosis, capacitive deionization, electrodialysis, and flow electrode capacitive deionization. This paper will briefly review each of these technologies and propose a new design to improve the current flow electrode capacitive deionization architecture. The new design uses a current collector flow-electrode architecture that has the potential to achieve record thermodynamic energy efficiencies. This formulation is proprietary to Lawrence Livermore National Laboratory.

36 MATERIALS SCIENCE↗
NASA NTRS1972

Domestic applications for aerospace waste and water management technologies

Some of the aerospace developments in solid waste disposal and water purification, which are applicable to specific domestic problems are explored. Also provided is an overview of the management techniques used in defining the need, in utilizing the available tools, and in synthesizing a solution. Specifically, several water recovery processes will be compared for domestic applicability. Examples are filtration, distillation, catalytic oxidation, reverse osmosis, and electrodialysis. Solid disposal methods will be discussed, including chemical treatment, drying, incineration, and wet oxidation. The latest developments in reducing household water requirements and some concepts for reusing water will be outlined.

Disanto, F.↗
DOE OSTI2026

Bipolar Membranes Electrodialysis for Water Purification and Resource Recovery

Reverse osmosis concentrate (ROC) from inland brackish water desalination and wastewater recycling presents moderate salinity, posing significant challenges for treatment and disposal. Existing treatment technologies predominantly rely on energy-intensive thermal methods, large-area evaporation strategies, or deep-well disposal, which often result in the loss of water value. Electrified membrane brine treatment offers a promising alternative by utilizing renewable energy sources, enabling complete water recycling. This work proposes the development of next-generation bipolar membrane electrodialysis (BMED) systems capable of desalinating brine while simultaneously recovering valuable resources. However, several critical challenges remain in the areas of membrane engineering for BMED. These include: 1) decreased current efficiency during desalination due to the low conductivity of feed chambers, 2) fouling and scaling from multivalent ions and contaminants in the feed, and 3) the retention and carryover of ROC contaminants, including PFAS compounds. Our research focuses on the development of novel anion exchange membranes (AEMs) and cation exchange membranes (CEMs) based on synthesized multiblock copolymers. We investigate the effects of block length, ion exchange capacity (IEC), and polymer backbone structure on cation and anion transport (e.g., Na+, Cl-, OH-, H+) for both our synthesized membranes and commercial membranes. Fundamental properties of these membranes, such as water uptake, IEC, and ionic conductivity, are also evaluated to optimize performance for BMED applications.

08 HYDROGEN↗
DOE OSTI2020

Separation characteristics of cations and natural organic matter in electrodialysis

Natural organic matter (NOM) in water can cause the formation of disinfection byproducts (DBPs) when NOM reacts with a disinfectant such as chlorine. Nanofiltration (NF) and reverse osmosis (RO) are effective treatment methods to remove NOM. However, the simultaneous presence of both NOM and divalent cations such as Ca 2+ can enhance fouling in NF and RO. Therefore, an appropriate pretreatment to remove such cations before NF or RO would delay fouling and perhaps improve water recovery and NOM removal efficiency. Electrodialysis (ED) is potentially an excellent pretreatment method because it separates inorganic ions well using ion exchange membranes (IEMs) but does not separate NOM well because of its size and consequent low diffusivity. This research focused on ion and NOM separation with ED using three different types of commercially available IEM pairs, two different commercially available NOM sources, and six different influents at 500 mg/L total dissolved solids in the presence or absence of both hardness (Ca 2+ and Mg 2+ ) and NOM. The target waters of interest in this research were drinking water supplies that require little or no desalination but substantial removal of NOM; after NOM separation in NF or RO, some or all of the ED concentrate can be added to the NF/RO permeate to create the finished water prior to disinfection. The results indicate that ED can effectively separate alkaline earth metal ions without separation of NOM. Cation exchange membranes with high exchange capacity, high selectivity for divalent cations are desirable, and both anion and cation exchange membranes should have low affinity for organic adsorption. As a result, the process would work particularly well for NOM with relatively low hydrophobicity, since NOM adsorption to most surfaces increases with hydrophobicity.

36 MATERIALS SCIENCE↗
NASA NTRS2024

Global Optimization via Quadratic Disjunctive Programming for Water Networks Design with Energy Recovery

Generalized disjunctive programming (GDP) models with bilinear and concave constraints, often seen in water network design, are challenging optimization problems. This work proposes quadratic and piecewise linear approximations for nonlinear terms to reformulate GDP models into quadratic GDP (QGDP) models that suitable solvers may solve more efficiently. We illustrate the benefits of the quadratic reformulation with a water treatment network design problem in which nonconvexities arise from bilinear terms in the mixers’ mass balances and concave investment cost functions of treatment units. Given the similarities with water network design problems, we suggest quadratic approximation for the GDP model for the optimal design of a large-scale reverse electrodialysis (RED) process. This power technology can recover energy from salinity differences between by-product streams of the water sector, such as desalination brine mixed with regenerated wastewater effluents. The solver Gurobi excels in handling QGDP problems, but weighing the problem’s precision and tractability balance is crucial. The piecewise linear approximation yields more accurate, yet larger QGDP models that may require longer optimization times in large-scale process synthesis problems.

Water Networks↗
NASA NTRS1991

Physical/chemical closed-loop water-recycling

Water needs, water sources, and means for recycling water are examined in terms appropriate to the water quality requirements of a small crew and spacecraft intended for long duration exploration missions. Inorganic, organic, and biological hazards are estimated for waste water sources. Sensitivities to these hazards for human uses are estimated. The water recycling processes considered are humidity condensation, carbon dioxide reduction, waste oxidation, distillation, reverse osmosis, pervaporation, electrodialysis, ion exchange, carbon sorption, and electrochemical oxidation. Limitations and applications of these processes are evaluated in terms of water quality objectives. Computerized simulation of some of these chemical processes is examined. Recommendations are made for development of new water recycling technology and improvement of existing technology for near term application to life support systems for humans in space. The technological developments are equally applicable to water needs on Earth, in regions where extensive water recycling is needed or where advanced water treatment is essential to meet EPA health standards.

Herrmann, Cal C.↗
NASA NTRS1990

Physical/chemical closed-loop water-recycling for long-duration missions

Water needs, water sources, and means for recycling water are examined in terms appropriate to the water quality requirements of a small crew and spacecraft intended for long duration exploration missions. Inorganic, organic, and biological hazards are estimated for waste water sources. Sensitivities to these hazards for human uses are estimated. The water recycling processes considered are humidity condensation, carbon dioxide reduction, waste oxidation, distillation, reverse osmosis, pervaporation, electrodialysis, ion exchange, carbon sorption, and electrochemical oxidation. Limitations and applications of these processes are evaluated in terms of water quality objectives. Computerized simulation of some of these chemical processes is examined. Recommendations are made for development of new water recycling technology and improvement of existing technology for near term application to life support systems for humans in space. The technological developments are equally applicable to water needs on earth, in regions where extensive water ecycling is needed or where advanced water treatment is essential to meet EPA health standards.

Herrmann, Cal C.↗