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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 1,279 records · Page 71
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Evaluation of hydrologic components of community land model 4 and bias identification

Runoff and soil moisture are two key components of the global hydrologic cycle that should be validated at local to global scales in Earth System Models (ESMs) used for climate projection. Here, we have evaluated the runoff and surface soil moisture output by the Community Climate System Model (CCSM) along with 8 other models from the Coupled Model Intercomparison Project (CMIP5) repository using satellite soil moisture observations and stream gauge corrected runoff products. A series of Community Land Model (CLM) runs forced by reanalysis and coupled model outputs was also performed to identify atmospheric drivers of biases and uncertainties in the CCSM. Results indicate that surface soil moisture simulations tend to be positively biased in high latitude areas by most selected CMIP5 models except CCSM, FGOALS, and BCC, which share similar land surface model code. With the exception of GISS, runoff simulations by all selected CMIP5 models were overestimated in mountain ranges and in most of the Arctic region. In general, positive biases in CCSM soil moisture and runoff due to precipitation input error were offset by negative biases induced by temperature input error. Excluding the impact from atmosphere modeling, the global mean of seasonal surface moisture oscillation was out of phase compared to observations in many years during 1985–2004. The CLM also underestimated runoff in the Amazon, central Africa, and south Asia, where soils all have high clay content. We hypothesize that lack of a macropore flow mechanism is partially responsible for this underestimation. However, runoff was overestimated in the areas covered by volcanic ash soils (i.e., Andisols), which might be associated with poor soil porosity representation in CLM. Finally, our results indicate that CCSM predictability of hydrology could be improved by addressing the compensating errors associated with precipitation and temperature and updating the CLM soil representation.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

A decomposition approach based on meta-heuristics and exact methods for solving a two-stage stochastic biofuel hub-and-spoke network problem

An alternative to the production of fossil transportation fuels is the production of biofuels, particularly, bioethanol. One of the main opportunity areas is the reduction in the overall cost of biofuel. An approach to reduce this cost is to design and implement a supply chain (SC) that considers the quality-related properties of the biomass as well as the economies of scale to minimize the logistics and quality-related costs. This problem is formulated as a hub location problem, which has been classified as an NP-hard problem, thus, meta-heuristics are a suitable approach to solve this problem. We propose a hybrid meta-heuristic solution procedure to solve large-scale instances of a two-stage stochastic biomass-to-biorefinery hub-and-spoke network problem. This solution procedure is proposed to support the large-scale production and distribution of bioethanol by considering the variability in its moisture and ash contents. The hybrid method utilizes a simulated annealing-simplex method to find an initial solution and a tabu search-simplex method to improve the solution. Numerical experimentation was performed on a realistic case study in Texas. The findings demonstrate that the hybrid procedure outperforms the standard L-shaped (LS) method. The meta-heuristic combining simulated annealing and tabu search with the simplex method (SATS-SM) achieved 2.48% lower costs and required 96.57% less time, on average, when compared to the results from using the LS.

09 BIOMASS FUELS↗
DOE OSTI2018

The influence of helium on deuterium retention in beryllium co-deposits

Tritium co-deposition with materials from the plasma-facing components is expected to be the main contributor to tritium retention in ITER. Since He will also be present in the plasma as fusion ash during the DT campaign, this study focuses on the effect of He on D retention in Be co-deposits. The PISCES-B linear plasma device was used to create co-deposited Be-D-He layers for various deposition temperatures (295 K - 475 K) and He concentrations in D - αHe plasma mixtures (0 ≤ α ≤ 0.1). Thermal desorption spectroscopy and nuclear reaction analysis were used to determine the D concentration in co-deposits. For the lowest He concentration (1%) an increase of D retention was observed for the deposition at room temperature, whereas for higher He concentrations a declining trend of D retention was found. Including 10% of He in the plasma is found to reduce D retention at deposition temperatures below 425 K and have a negligible effect at higher deposition temperatures.

36 MATERIALS SCIENCE↗
DOE OSTI2013

Synthesis and characterization of LTA nanozeolite using barley husk silica: Mercury removal from standard and real solutions

Highlights: ► Silica extraction from barley husk with high purity for the synthesis of A nanozeolite. ► Free template A nanozeolite synthesized via new source of silica at low temperature. ► Optimization of SiO{sub 2}/Al{sub 2}O{sub 3}, Na{sub 2}O/SiO{sub 2} ratios, temperature and time of the synthesis. ► Utilizing of synthesized A nanozeolite for mercury removal from aqueous solutions. ► Mercury removal at optimized pH, contact time and adsorbent dose from real solution. - Abstract: In this study, synthesized Lined Type A (LTA) nanozeolite from barley husk silica (BHS) was used for mercury removal from standard and real aqueous solutions. The BHS in amorphous phase with 80% purity was extracted from barley husk ash (BHA), and used effectively as a new source of silica for the synthesis of NaA nanozeolite. The NaA nanocrystal in pure phase has been synthesized at low temperature, without adding any organic additives. The effects of heating time, reaction temperature, SiO{sub 2}/Al{sub 2}O{sub 3}, and Na{sub 2}O/SiO{sub 2} mole ratios on the crystallization of NaA nanozeolite were studied. The adsorption capacity of mercury (II) was studied as a function of pH, contact time, and amount of adsorbent. The crystallization of NaA nanozeolite from BHS was characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), Brunauer–Emmett–Teller (BET), and FTIR techniques. Moreover, concentration of Hg{sup 2+} ions in the aqueous solutions was analyzed by hydride generation atomic absorption spectroscopy method (HG-AAS). The standard and real samples analysis showed that NaA nanozeolite is capable of Hg{sup 2+} ions removal from the aqueous solutions. Efficiency of mercury (II) adsorption from real solutions onto the nano-sized NaA zeolite was 98%.

36 MATERIALS SCIENCE↗
DOE OSTI2017

D retention in Be exposed to fusion relevant mixed species $\mathrm{D_2 - He}$ plasma

He admixture to D 2 plasma incident on Be targets is used to study the influence of a fusion-ash relevant He concentration on D retention. A variation of exposure parameters such as He ion fraction: 0.02 ≤ α ≤ 0.1, exposure temperature: 330 ≤ T exp ≤ 650 K, ion-fluence: 5 × 10 24 ≤ Φ ≤ 1 × 10 27 m -2 and energy: 40 ≤ E i ≤ 90 eV, are explored. Results are compared to D retention values in Be observed in D2 plasma ( α = 0). With α = 0.1, a factor ~3 reduction in D retention is noted for exposure at ~300 K, but is less as Texp approaches ~473 K, and not apparent above 473 K. The reduction is caused by the ability of He to hinder D saturation in low-release-temperature supersaturated binding states.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2012

The NOvA Experiment: Status and Outlook

The NOvA long-baseline neutrino oscillation experiment is currently under construction and will use an upgraded NuMI neutrino source at Fermilab and a 14-kton detector at Ash River, Minnesota to explore the neutrino sector. NOvA uses a highly active, finely segmented detector design that offers superb event identification capability, allowing precision measurements of @n_e/@n@?_e appearance and @n_@m/@n@?_@m disappearance, through which NOvA will provide constraints on @q_1_3, @q_2_3, |@Dm_a_t_m^2|, the neutrino mass hierarchy, and the CP-violating phase @d. In this article, we review NOvA@?s uniquely broad physics scope, including sensitivity updates in light of the latest knowledge of @q_1_3, and we discuss the experiment@?s construction and operation timeline.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2021

Trace impurity transport in multi-species plasmas with large particle fluxes

A burning fusion plasma has a large inwards flux of fuel and outwards flux of ash. Existing impurity transport theories do not account for a steady-state environment of such large fluxes. In this paper, we extend classical transport theory to account for a background of such fluxes. In a mainly two-ion species magnetized plasma, with oppositely directed density gradients maintained by oppositely directed sources of the two species, trace impurity ions are shown to align with the larger mass ions. This unexpected behavior is derived analytically and simulated numerically using the MITNS (Multiple-Ion Transport Numerical Solver) code. Overall, the result suggests a potential advantage of edge-fueled p-B11 fusion in extracting high-Z impurities, and possible applications in plasma-based separation methods.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2025

Life-cycle greenhouse gas emissions analysis of battery-grade lithium production in Finland

Various countries are undertaking initiatives to domestically produce battery-related critical materials. Within Finland, Keliber Technology Oy is developing capabilities for battery-grade lithium hydroxide monohydrate (LHM) production from spodumene ores. A detailed life-cycle assessment (LCA) of this pathway is conducted to determine its life-cycle GHG impacts using Argonne's R&D GREET (Research and Development Greenhouse gases, Regulated Emissions, and Energy use in Technologies) model. The analysis shows life-cycle GHG emissions of similar to 9.2 kg CO 2-eq /kg LHM, dominated by contributions from three energy sources - diesel, natural gas, and electricity - and two material inputs - lime (CaO) and soda ash (Na 2 CO 3 ). Sensitivity analyses highlight the potential to reduce these impacts using low-carbon electricity, sequestration of process CO 2 emissions generated during CaO and Na 2 CO 3 production, and bio-based energy for LHM production (by similar to 15 % each). A comparative analysis shows lower impacts for Keliber's LHM than for existing LHM production from Australian spodumene ores processed in China (by similar to 40 %).

CCS↗
DOE OSTI2023

Adsorption of rare earth elements in carboxylated mesoporous carbon

The separation of Rare Earth Elements (REEs) from various non-conventional sources is critically important to maintain the supply–demand balance of REEs in the western world. Here, in this research, we have investigated coal Fly Ash (CFA) as the non-conventional source of REEs. In order to recover REEs, we have synthesized carboxylate-functionalized mesoporous carbon (CMC) to harness the chelation-induced adsorption of REEs. These adsorbents were characterized with pore textural properties, FTIR spectroscopy, and SEM-EDX mapping. In the initial study with single-component La(III) Dy(III) and Lu(III), it was revealed that CMC can adsorb those REEs 2–4 times more than that of pristine mesoporous carbon confirming the effective role of the carboxylate group in the REE separation. Furthermore, the affiliation of the carboxylate group towards heavier REEs (Lu>Dy>La, when present is equal amounts) provides an added benefit of this adsorbent owing to the high demand for heavier REEs in the technology sectors. The leachate solution produced from CFA contained sixteen REEs in the range of 50–200 ppb for most of the REEs. It was revealed that CMC can extract 80–90% of all the REEs thereby further confirming the success of the CMC as an effective REE sorbent. Three successive cycles of adsorption and desorption of REEs with the same CMC revealed the consistent adsorption capacity of REEs. In-situ X-ray Absorption Near Edge Spectroscopy (XANES) analysis confirmed the +3 oxidation states of La, Dy, and Lu within CMC. In-situ Extended X-ray Absorption Fine Structure (EXAFS) analysis revealed the shortening of mean La-O, Dy-O, and Lu-O bond distance by 0.03–0.05 Å thereby confirming the coordination of these REEs with carboxylate groups present on CMC.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Regeneration of anion-exchange resins for cyclic selenium removal from industrial wastewaters

Application of ion exchange for the removal of selenium (Se) oxyanions from industrial wastewaters is often limited by ineffective regeneration of the ion-exchange resins, particularly in complex systems containing competing ions, such as coal-ash leachate containing high-sulfate concentrations and heavy metal ions. Here, in this study, it was first demonstrated that while conventional regeneration with sodium chloride (NaCl) is effective for simulated wastewater, with ∼80% efficiency, NaCl fails to regenerate resin loaded with real industrial wastewater, achieving less than 20% efficiency. To overcome this challenge, a two-step regeneration process was investigated using a sodium carbonate (Na 2 CO 3 ) solution for elution, followed by a NaCl solution for restoration. Compared to the one-step NaCl regeneration, this integrated process restored more than 80% of the resin's capacity with real industrial wastewaters. Beyond demonstrating regeneration performance, this research emphasizes fundamental mechanistic interpretations of the observed regeneration behavior across different water matrices and experimental conditions. Particularly, accounting for pH-dependent carbonate speciation, it is proposed that the elution step exploits the resin's strong affinity for divalent carbonate ions to displace strongly bound contaminants, while the subsequent restoration step relies mainly on the mass action effects of chloride ions to regenerate the resin sites. The protocol was optimized to achieve rapid regeneration (<10 min) using moderate chemical concentrations (0.5 M) in treating real leachate. In batch cyclic experiments, Se regeneration reached nearly complete recovery after five consecutive sorption and desorption cycles, while in the fixed-bed system, the regeneration efficiency remained at approximately 80% after five cycles.

Anion-exchange resin↗
DOE OSTI2012

Thermodynamic estimation of minor element distribution between immiscible liquids in Fe-Cu-based metal phase generated in melting treatment of municipal solid wastes

Graphical abstract: Display Omitted Highlights: Black-Right-Pointing-Pointer Two liquids separation of metal occurs in the melting of municipal solid waste. Black-Right-Pointing-Pointer The distribution of PGMs etc. between two liquid metal phases is studied. Black-Right-Pointing-Pointer Quite simple thermodynamic model is applied to predict the distribution ratio. Black-Right-Pointing-Pointer Au and Ag originated from WEEE are found to be concentrated into Cu-rich phase. - Abstract: Waste electrical and electronic equipment (WEEE) has become an important target in managing material cycles from the viewpoint of not only waste management and control of environmental pollution but also resource conservation. This study investigated the distribution tendency of trace elements in municipal solid waste (MSW) or incinerator ash, including valuable non-ferrous metals (Ni, Co, Cr, Mn, Mo, Ti, V, W, Zr), precious group metals (PGMs) originated from WEEE (Ag, Au, Pd, Pt), and others (Al, B, Pb, Si), between Fe-rich and Cu-rich metal phases by means of simple thermodynamic calculations. Most of the typical alloying elements for steel (Co, Cr, Mo, Nb, Ni, Si, Ti, V, and W) and Rh were preferentially distributed into the Fe-rich phase. PGMs, such as Au, Ag, and Pd, were enriched in the Cu-rich phase, whereas Pt was almost equally distributed into both phases. Since the primary metallurgical processing of Cu is followed by an electrolysis for refining, and since PGMs in crude copper have been industrially recovered from the resulting anode slime, our results indicated that Ag, Au, and Pd could be effectively recovered from MSW if the Cu-rich phase could be selectively collected.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2013

Recovery of lithium and cobalt from waste lithium ion batteries of mobile phone

Graphical abstract: Recovery of valuable metals from scrap batteries of mobile phone. - Highlights: • Recovery of Co and Li from spent LIBs was performed by hydrometallurgical route. • Under the optimum condition, 99.1% of lithium and 70.0% of cobalt were leached. • The mechanism of the dissolution of lithium and cobalt was studied. • Activation energy for lithium and cobalt were found to be 32.4 kJ/mol and 59.81 kJ/mol, respectively. • After metal recovery, residue was washed before disposal to the environment. - Abstract: In view of the stringent environmental regulations, availability of limited natural resources and ever increasing need of alternative energy critical elements, an environmental eco-friendly leaching process is reported for the recovery of lithium and cobalt from the cathode active materials of spent lithium-ion batteries of mobile phones. The experiments were carried out to optimize the process parameters for the recovery of lithium and cobalt by varying the concentration of leachant, pulp density, reductant volume and temperature. Leaching with 2 M sulfuric acid with the addition of 5% H{sub 2}O{sub 2} (v/v) at a pulp density of 100 g/L and 75 °C resulted in the recovery of 99.1% lithium and 70.0% cobalt in 60 min. H{sub 2}O{sub 2} in sulfuric acid solution acts as an effective reducing agent, which enhance the percentage leaching of metals. Leaching kinetics of lithium in sulfuric acid fitted well to the chemical controlled reaction model i.e. 1 − (1 − X){sup 1/3} = k{sub c}t. Leaching kinetics of cobalt fitted well to the model ‘ash diffusion control dense constant sizes spherical particles’ i.e. 1 − 3(1 − X){sup 2/3} + 2(1 − X) = k{sub c}t. Metals could subsequently be separated selectively from the leach liquor by solvent extraction process to produce their salts by crystallization process from the purified solution.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Recovery of valuable components from waste LCD panel through a dry physical method

Highlights: • This paper aims at harmless treatment and resource recovery of waste LCD panel. • Indium tin oxide (ITO) was enriched from CF and TFT glass through mechanical exfoliation. • Vibrated gas-solid fluidized bed separation was introduced to investigate the separation of polarizing film and glass. •One flowsheet for recycling waste LCD panel synthetically which combine dry methods is proposed. - Abstract: A waste liquid crystal display (LCD) panel was recycled synthetically and cleanly by using dry physical methods, namely, mechanical exfoliation, dry crushing and vibrated gas–solid fluidized bed separation. Results of elemental and phase analyses show that indium and tin contents were enriched greatly in indium tin oxide concentrate obtained from colour filter and thin-film transistor glass. The results of crushing, ash content and scanning electron microscopic analyses show that when the LCD panel was crushed into particles smaller than 0.25 mm, the polarizer film is nearly completely liberated from the glass. Moreover, the results of vibrated gas–solid fluidized bed separation show that gas velocity and separation time are the main factors influencing the separation. The vibration intensity of 6.8, gas velocity of 13.6 cm/s and fluidizing time of 30 s are the optimum operating parameters, and the degree of separation and recovery of polarizing film reached up to 37.69 and 72.3%, respectively. Based on these results, the combination of dry enrichment, dry crushing and dry separation in a flowsheet is proposed for recycling of waste LCD panel.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Characterization of biochar prepared from biogas digestate

Highlights: • Solid digestate (SD) is a potential feedstock for preparing biochars. • The optimal BET surface area of resulting biochar from SD is over 100 m{sup 2}/g. • The higher temperature leads to the increase in true density of resulting biochar, but exhibited a decreased higher heating value. • The SD-based biochar may be used as a biofertilizer due to the mesoporosity and the abundant in nutrient minerals. - Abstract: In the study, the biogas digestate was evaluated as a potential feedstock for preparing biochars at a broad temperature range of 300–900 °C. The physico-chemical and pore properties of the resulting biochars (denoted as SDBC, solid digestate biochar), including calorific value (higher heating value), surface area/pore volume/pore size distribution, true density, scanning electron microscopy – energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray powder diffraction (XRD), were studied. It was found that the higher heating values of the SDBC products were on a decreasing trend as pyrolysis temperature increased, but they indicated an increase in true density. The results are probably associated with the active pyrolysis of the lignocellulosic fragments and the calcination (or shrinkage) processes, thus resulting in the increased contents of aromatic carbon clusters and main mineral constituents remained. Based on the pore properties, pyrolysis temperature at around 800 °C seemed to be the optimal condition for producing SDBC, where its Brunauer-Emmet-Teller (BET) surface area (>100 m{sup 2}/g) largely increased as compared to that of the digestate feedstock (<1 m{sup 2}/g). Furthermore, the main compositions of mineral ash in the resulting biochar could exist as phosphates, carbonates, or oxides of calcium and other alkali/alkaline earth elements. According to the data on EDS and XRD, more pores could be significantly generated under severe pyrolysis (>700 °C) due to the high aromaticity via the thermal decomposition of lignocelluloses and the volatilization of inorganic minerals.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Fate of metals and emissions of organic pollutants from torrefaction of waste wood, MSW, and RDF

Highlights: •MSW, RDF and waste wood fuel blends were torrefied at 220 °C. •Chlorine is separated from metals catalytically active in PCDD/F formation. •Torrefaction of MSW and RDF reduces the risk for alkali-chloride corrosion in WtE. •Torrefaction of MSW generates less PCDD/F than RDF when combined with DC. -- Abstract: Torrefaction of municipal solid waste (MSW), refuse-derived fuel (RDF), and demolition and construction wood (DC) was performed at 220 °C and a residence time of 90 min in a bench-scale reactor. The levels of toxic polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) contained in emission from the torrefaction process were evaluated. In addition, main ash-forming elements and trace metals in the raw feedstock and char were determined. The use of MSW in fuel blends with DC resulted in lower PCDD and PCDF emissions after torrefaction, compared with the RDF blends. The migration of chlorine from the feedstock to the gas phase reduces the chlorine content of the char which may reduce the risk of alkali chloride-corrosion in char combustion. However, trace metals catalytically active in the formation of PCDD and PCDF remain in the char, thereby may promote PCDD and PCDF formation during subsequent char combustion for energy recovery; this formation is less extensive than when the feedstock is used.

09 BIOMASS FUELS↗
DOE OSTI2026

Production of high-quality polyethylene (PE) films from post-consumer shrink wrap with solvent targeted recovery and precipitation (STRAP)

The solvent-targeted recovery and precipitation (STRAP™) process separates polymers from contaminants present in the feedstock. In this work, we demonstrate the recyclability of a post-consumer waste (PCW) shrink wrap that contains inks, adhesives, and paper using STRAP. We produced a clear rPE cast film from the PCR shrink wrap with no visual contamination from paper or inks. STRAP decreased the ash content from 0.96 wt% to 0.24 wt%. A techno-economic analysis (TEA) shows that a STRAP plant processing 50,000 metric tons annually of shrink wrap waste (purchased at $\$0.25$/kg) containing 85 wt% PE can achieve an IRR of 16.2% when selling rPE at $\$1.30$/kg, an IRR of 10.7% with an rPE price of $\$1.00$/kg, or an IRR of 3.79% with an rPE price of $\$0.70$/kg. Furthermore, the life cycle assessment (LCA) shows a 64% reduction in global warming potential (kg CO 2 equivalent) when compared to the production of virgin LDPE. As a result, this work shows how feedstocks with insoluble impurities can be recycled using STRAP on a large scale.

Radkevich, Elizaveta [University of Wisconsin-Madi↗
DOE OSTI2012

Algal Biomass Constituent Analysis: Method Uncertainties and Investigation of the Underlying Measuring Chemistries

Algal biomass compositional analysis data form the basis of a large number of techno-economic process analysis models that are used to investigate and compare different processes in algal biofuels production. However, the analytical methods used to generate these data are far from standardized. This work investigated the applicability of common methods for rapid chemical analysis of biomass samples with respect to accuracy and precision. This study measured lipids, protein, carbohydrates, ash, and moisture of a single algal biomass sample at 3 institutions by 8 independent researchers over 12 separate workdays. Results show statistically significant differences in the results from a given analytical method among laboratories but not between analysts at individual laboratories, suggesting consistent training is a critical issue for empirical analytical methods. Significantly different results from multiple lipid and protein measurements were found to be due to different measurement chemistries. We identified a set of compositional analysis procedures that are in best agreement with data obtained by more advanced analytical procedures. The methods described here and used for the round robin experiment do not require specialized instrumentation, and with detailed analytical documentation, the differences between laboratories can be markedly reduced.

09 BIOMASS FUELS↗