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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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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Review of Dynamic Recovery Effects on Ion Irradiation Damage in Ionic-Covalent Materials

Single crystalline samples of highly ionic Ca2La8(SiO4)6O2 and covalent 6H–SiC have been irradiated with different ions/energies to study the effects of dose, temperature, damage-energy density, and in-cascade ionization rate on the dynamics of irradiation-induced amorphization. Above temperatures of 100–150 K, the dose for complete amorphization, D, increases with temperature in a single stage and exhibits a strong dependence on the ratio of in-cascade recovery to displacement cross sections, σr/σd. A fit of a dynamic model for amorphization to these data indicates that irradiation-induced dynamicrecovery occurs with an activation energy of 0.15 ± 0.02 and 0.12 ± 0.01 eV for Ca2La8(SiO4)6O2 and 6H–SiC, respectively. Analysis of these data reveals that ionization processes are the dominant contributor to in-cascade recovery in Ca2La8(SiO4)6O2; while in 6H–SiC, ionization processes are less dominant.

Environmental Molecular Sciences Laboratory↗
DOE OSTI2012

Microbial Enhanced Oil Recovery in Fractional-Wet Systems: A Pore-Scale Investigation

Microbial enhanced oil recovery (MEOR) is a technology that could potentially increase the tertiary recovery of oil from mature oil formations. However, the efficacy of this technology in fractional-wet systems is unknown, and the mechanisms involved in oil mobilization therefore need further investigation. Our MEOR strategy consists of the injection of ex situ produced metabolic byproducts produced by Bacillus mojavensis JF-2 (which lower interfacial tension (IFT) via biosurfactant production) into fractional-wet cores containing residual oil. Two different MEOR flooding solutions were tested; one solution contained both microbes and metabolic byproducts while the other contained only the metabolic byproducts. The columns were imaged with X-ray computed microtomography (CMT) after water flooding, and after MEOR, which allowed for the evaluation of the pore-scale processes taking place during MEOR. Results indicate that the larger residual oil blobs and residual oil held under relatively low capillary pressures were the main fractions recovered during MEOR. Residual oil saturation, interfacial curvatures, and oil blob sizes were measured from the CMT images and used to develop a conceptual model for MEOR in fractional-wet systems. Overall, results indicate that MEOR was effective at recovering oil from fractional-wet systems with reported additional oil recovered (AOR) values between 44 and 80%; the highest AOR values were observed in the most oil-wet system.

02 PETROLEUM↗
DOE OSTI2023

Study of Different Formulations for the Multiperiod Blending Problem Applied to Lithium Recovery from Produced Water

We present several formulations to solve the MPBP for the recovery of REE/CMs from produced water and propose a decomposition approach thatleverages strategies in general disjunctive programming to enhance its performance. We compare these proposed formulations/strategies via two illustrative case studies on recovering lithium from a network of produced water sources.

Ovalle, Daniel↗
DOE OSTI2020

Uranium recovery from seawater using amidoxime-based braided polymers synthesized from acrylic fibers

Global demand for nuclear energy is expected to rise in the coming decades. To meet these growing needs, new uranium resources must be explored. One of the potential alternatives to traditional uranium mining is oceanic uranium. The capture and recovery of uranium from the ocean has been under investigation for some time, with many recent studies focused on amidoxime based adsorbents. These adsorbents while able to achieve high uranium recovery capacities are, nevertheless, expensive to produce and adsorb a significant amount of hard to remove vanadium. The purpose of this study is to evaluate the adsorption performance of amidoxime based polymer braids synthesized from acrylic fibers which are designed to significantly cut polymer synthesis and conditioning costs. Adsorption experiments were performed in a recirculating raceway flume system at environmental conditions, approximately 10.8 oC, with 40-micron prefiltered seawater over 28 days for small and large sized LCW polymer braids. For both braid sizes, the adsorption of vanadium was far lower on the LCW materials than on Oak Ridge National Laboratory’s amidoxime based AF1 and AI8 small braids, with the LCW small braids outperforming both materials with respect to uranium adsorption under similar conditions. Adsorption modeling was used to simulate the performance at higher temperatures based on 20oC experiments previously performed with similar materials. Simulation results indicated that the small LCW braids would have a less significant advantage with respect to uranium adsorption over both AF1 and AI8 at 20oC and adsorb slightly less uranium than AF1 at 31oC. Vanadium adsorption by LCW small braids was less than one third of vanadium adsorption by either AF1 or AI8 for all temperatures. This behavior indicates that the LCW materials are able to achieve comparable uranium adsorption to other amidoxime adsorbents previously developed, while being cheaper to produce and adsorbing significantly less vanadium.

Wiechert, Alexander I.↗
DOE OSTI2026

Optimizing Heat Recovery with Storage: Control Validation and Sensitivity Analysis of the Time-Independent Energy Recovery Plant Using Modelica

Heat recovery in large building central plants saves energy but traditionally requires simultaneous heating and cooling. The Time-Independent Energy Recovery (TIER) plant shifts this paradigm by integrating thermal energy storage (TES) to enable heat recovery regardless of concurrent demand, offering a highly efficient, space-saving solution to achieve California’s energy goals. However, its integration of heat recovery chillers, cooling-only chillers, cooling towers, and trim air-source heat pumps (ASHPs) creates growing control and sizing complexity. To overcome this, this study employs high-fidelity Modelica dynamic simulation to validate TIER control sequences and optimize equipment sizing. We translated the written Sequences of Operation into executable Control Description Language (CDL) to test logic against sub-hourly loads. This verification workflow successfully identified and resolved critical vulnerabilities, such as thermal storage freezing and equipment short-cycling, in a virtual environment prior to physical deployment. Then, the study analyzes TIER plant performance across three simulated building types in three locations, and a real building load profile, ensuring variety in heating and cooling loads, and simultaneity factors and explores sizing rules for the TES and ASHP capacity. The analysis shows that the TIER plant operates equipment efficiently leading to a plant SCOP of around 7.5 across all scenarios, higher than a traditional ASHP plant, and a viable pathway to de-risk complex system design and control through simulation to identify optimal designs that maximize energy efficiency, minimize operational costs, and ensure robust operation in varied environmental conditions, thereby facilitating the broader adoption of such a solution for large buildings.

Zanetti, Ettore↗
DOE OSTI2016

Evaluating Online Global Recovery with Fenix Using Application-Aware In-Memory Checkpointing Techniques

Exascale systems promise the potential for computation at unprecedented scales and resolutions, but achieving exascale by the end of this decade presents significant challenges. A key challenge is due to the very large number of cores and components and the resulting mean time between failures (MTBF) in the order of hours or minutes. Since the typical run times of target scientific applications are longer than this MTBF, fault tolerance techniques will be essential. An important class of failures that must be addressed is process or node failures. While checkpoint/restart (C/R) is currently the most widely accepted technique for addressing processor failures, coordinated, stable-storage-based global C/R might be unfeasible at exascale when the time to checkpoint exceeds the expected MTBF. This paper explores transparent recovery via implicitly coordinated, diskless, application-driven checkpointing as a way to tolerate process failures in MPI applications at exascale. The discussed approach leverages User Level Failure Mitigation (ULFM), which is being proposed as an MPI extension to allow applications to create policies for tolerating process failures. Specifically, this paper demonstrates how different implementations of application-driven in-memory checkpoint storage and recovery compare in terms of performance and scalability. We also experimentally evaluate the effectiveness and scalability of the Fenix online global recovery framework on a production system -the Titan Cray XK7 at ORNL- and demonstrate the ability of Fenix to tolerate dynamically injected failures using the execution of four benchmarks and mini-applications with different behaviors.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2017

Process evaluation and flowsheet development for the recovery of rare earth elements from coal and associated byproducts

Coal and coal byproducts produced annually contain enough rare earth elements (REEs) to meet current U.S. demand. Here, the REEs exist in the form of minerals, ion-exchanged elements associated with clays and chemically bonded elements within the organic coal matrix. Researchers at three universities have collaborated to evaluate the effectiveness of existing physical and chemical concentration processes for the recovery of the REEs. The efforts have found that physical separation processes can increase the total REE content in the thickener underflow material collected from a Central Appalachian coal cleaning facility from around 300 ppm to values greater than 17,500 ppm on an ash basis. Leaching followed by solvent extraction was found to be the most effective to recover the REEs from coarse middlings materials collected from multiple coal basins as indicated by recovery values exceeding 80%. Based on material characterization data and process evaluations conducted for several potential feed coal sources, economic recovery of the REEs will require byproduct production of both clean coal and REE concentrate using a process flowsheet that is unique for each source.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2022

Energy Resilient Recovery in Puerto Rico: Hurricane Maria Recovery Support

This report covers microgrids as a special application of distributed energy resources (DERs) in Puerto Rico. This is one of a series of reports describing the U.S. Department of Energy (DOE) multi-laboratory efforts undertaken. To ensure the sustainable, long-term recovery of Puerto Rico's electric power grid from hurricanes Maria and Irma and to build capacity to manage future potential natural disasters in the most secure and resilient way, DOE convened experts from multiple national laboratories to develop a comprehensive set of data, models, analytic tools, and studies, considering inputs from a wide variety of stakeholder groups, to support technically sound recommendations for Puerto Rico's energy investment decisions. In Phase 1 of the multi-laboratory effort to support Puerto Rico's recovery, the National Renewable Energy Laboratory (NREL) provided the utility company Puerto Rico Electric Power Authority (PREPA) recommendations for a new framework of interconnection standards to accelerate the integration of utility-scale, transmission-connected, renewable electrical generation and energy storage that ensure cross-technology compatibility and enable high deployment levels without compromising grid reliability, safety, or security (https://www.nrel.gov/docs/fy19osti/73848.pdf). In Phase 2, NREL published a report focused on the interconnection of distributed energy resources (DERs) to the electric distribution system in Puerto Rico (https://www.nrel.gov/docs/fy21osti/77127.pdf). This report familiarized the reader with Puerto Rico's distribution infrastructure and operational practices and procedures that are relevant to DER interconnection. The report also provided considerations for streamlining the interconnection process given the expected increase in deployments resulting from Puerto Rico's renewable portfolio standard goal of 100% renewables by 2050. Accordingly, the report identifies considerations and concerns associated with the increase in intermittent generation, strategies for DER interconnection best practices, and the potential use of the latest technological solutions identified in the latest revision of the Institute of Electrical and Electronics Engineers 1547-2018 interconnection standard. Additionally, the report identified ways to improve the physical resiliency of installed DERs. This task describes how distributed energy systems may participate in and contribute to improving the resiliency of Puerto Rico's energy infrastructure in the future. This report presents an analysis of the Puerto Rico grid to illustrate the possible different microgrid and minigrid scenarios. The capability to form sustained microgrids and minigrids has the potential to provide a high level of resiliency during disturbances on the grid. DERs, on the other hand, have the capability to aid in the microgrid operation by providing grid support as well as grid-forming functionality. Other tasks in Phase 3 include voltage regulation in distribution networks using DERs and transmission-and-distribution co-simulation.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2014

Uranium recovery from seawater: development of fiber adsorbents prepared via atom-transfer radical polymerization

We developed a novel adsorbent preparation method using atom-transfer radical polymerization (ATRP) combined with radiation-induced graft polymerization (RIGP) in order to synthesize an adsorbent for uranium recovery from seawater. Furthermore, the ATRP method allowed a much higher degree of grafting on the adsorbent fibers (595 2818%) than that allowed by RIGP alone. The adsorbents were prepared with varied composition of amidoxime groups and hydrophilic acrylate groups. The successful preparation revealed that both ligand density and hydrophilicity were critical for optimal performance of the adsorbents. Adsorbents synthesized in this study showed a relatively high performance (141 179 mg/g at 49 62 % adsorption) in laboratory screening tests using a uranium concentration of ~6 ppm. This performance is much higher than that of known commercial adsorbents. However, actual seawater experiment showed impeded performance compared to the recently reported high-surface-area-fiber adsorbents, due to slow adsorption kinetics. The impeded performance motivated an investigation of the effect of hydrophilic block addition on the graft chain terminus. The addition of hydrophilic block on the graft chain terminus nearly doubled the uranium adsorption capacity in seawater, from 1.56 mg/g to 3.02 mg/g. Our investigation revealed the importance of polymer chain conformation, in addition to ligand and hydrophilic group ratio, for advanced adsorbent synthesis for uranium recovery from seawater.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2023

Separation, Recovery and Upgrading of 2,3-Butanediol from Fermentation Broth

2,3-Butanediol (BDO) is a bio-derived building block available from biomass through biochemical methods in high titers (>120 g L-1) making it an attractive target for production and further upgrading to chemical products and fuels such as sustainable aviation fuel. A key challenge to enable the adoption of BDO as a precursor is the effective separation and isolation of this molecule from the fermentation broth. 2,3-Butanediol has a boiling point higher than that of water (177 degrees C), and as a consequence, separation via distillation methods is an energy-intensive and therefore costly approach. We have improved the BDO separation through conversion to a 1,3-dioxolane directly in fermentation broth via reaction with bio-derived aldehydes catalyzed by a solid acid catalyst. The resulting dioxolane phase separates from the fermentation broth, allowing for easy decantation and isolation in >90% isolated yield. Isolated dioxolane can be used directly as a compression iginition fuel, trans-acetalized to recover high-purity BDO or used directly in a catalytic process as a BDO synthon to produce methyl ethyl ketone with aldehyde recovery in near quantitative yield.

aviation fuel↗
DOE OSTI2018

Uranium Resource Recovery from Desalination Plant Feed and Reject Water Using Amidoxime Functionalized Adsorbent

With global demand for nuclear power expected to rise, new nuclear fuel resources must be explored to ensure the viability and sustainability of nuclear power. Uranium recovery from seawater is one potential source, though the low concentration of uranium in seawater is a significant obstacle. As a concentrate of seawater, desalination brine reject would have a significantly higher uranyl concentration. In this work, the adsorption of uranium and competing ions in brine reject is investigated. Adsorption experiments were performed over 84 days in 5-gallon batch tanks with amidoxime adsorbents and samples taken from the feed seawater and reverse osmosis brine reject of the Tampa Bay Desalination Plant. The aqueous concentration and adsorbed mass of uranium, zinc, copper, iron, vanadium, calcium, and magnesium were determined through inductively coupled plasma mass spectroscopy. Aqueous adsorption modeling was used to simulate speciation and adsorption of these ions under the experimental conditions. The adsorbed mass of uranium in seawater was 6.22 mg/g adsorbent which declined to 3.95 mg/g in brine. This is a result of increased competition from iron and vanadium whose adsorbed masses increased from 1.06 to 3.00 mg/g and 1.05 to 2.67 mg/g, respectively. Good agreement between experimental and predicted results was obtained for all ions in seawater. Uranium adsorption was overpredicted in brine which may be attributed to the presence of other competing ions and the system not being at equilibrium. Furthermore, results demonstrate that the influence of competing ions, such as those of iron and vanadium, on uranium adsorption would need to be reduced for brine reject to become a significant uranium resource.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Large fluxes of fatty acids from membranes to triacylglycerol and back during N-deprivation and recovery in Chlamydomonas

Abstract Microalgae accumulate triacylglycerol (TAG) during nutrient deprivation and break it down after nutrient resupply, and these processes involve dramatic shifts in cellular carbon allocation. Due to the importance of algae in the global carbon cycle, and the potential of algal lipids as feedstock for chemical and fuel production, these processes are of both ecophysiological and biotechnological importance. However, the metabolism of TAG is not well understood, particularly the contributions of fatty acids (FAs) from different membrane lipids to TAG accumulation and the fate of TAG FAs during degradation. Here, we used isotopic labeling time course experiments on Chlamydomonas reinhardtii to track FA synthesis and transfer between lipid pools during nitrogen (N)-deprivation and resupply. When cells were labeled before N-deprivation, total levels of label in cellular FAs were unchanged during subsequent N-deprivation and later resupply, despite large fluxes into and out of TAG and membrane lipid pools. Detailed analyses of FA levels and labeling revealed that about one-third of acyl chains accumulating in TAG during N-deprivation derive from preexisting membrane lipids, and in total, at least 45% of TAG FAs passed through membrane lipids at one point. Notably, most acyl chains in membrane lipids during recovery after N-resupply come from TAG. Fluxes of polyunsaturated FAs from plastidic membranes into TAG during N-deprivation were particularly noteworthy. These findings demonstrate a high degree of integration of TAG and membrane lipid metabolism and highlight a role for TAG in storage and supply of membrane lipid components.

Plant Sciences↗