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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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Removing Cs within a continuous flow set-up by an ionic exchanger material transformable into a final waste form
Silica monoliths loaded with hexacyanoferrate (HCF) nanoparticles were designed and synthesized to selectively remove Cs + ions from an aqueous saline solution within a continuous flow set-up. The decontamination and hydrodynamic efficiency of this smart material was compared to other granularly supported HCF. Finally, a thermal treatment was applied to transform the HCF functionalized monolith into a final waste form matrix.
Effect of pelleting process variables on physical properties and sugar yields of ammonia fiber expansion pretreated corn stover
Pelletization process variables including grind size (4, 6 mm), die speed (40, 50, 60 Hz), and preheating (none, 70 degrees C) were evaluated to understand their effect on pellet quality attributes and sugar yields of ammonia fiber expansion (AFEX) pretreated biomass. The bulk density of the pelletized AFEX corn stover was three to six times greater compared to untreated and AFEX-treated corn stover. Also the durability of the pelletized AFEX corn stover was >97.5% for all pelletization conditions studied except for preheated pellets. Die speed had no effect on enzymatic hydrolysis sugar yields of pellets. Pellets produced with preheating or a larger grind size (6 mm) had similar or lower sugar yields. Pellets generated with 4 mm AFEX-treated corn stover, a 60 Hz die speed, and no preheating resulted in pellets with similar or greater density, durability, and sugar yields compared to other pelletization conditions.
Moderate temperature sintering of BaZr 0.8 Y 0.2 O 3-δ protonic ceramics by A novel cold sintering pretreatment
The state-of-the-art protonic ceramic conductor BaZr 0.8 Y 0.2 O 3-δ (BZY20) requires an extremely high sintering temperature (≥1700 °C) to achieve the desired relative density and microstructure necessary to function as a proton conducting electrolyte. In this work, we developed a cold sintering pretreatment assisted moderate-temperature sintering method for the fabrication of high-quality pure BZY20 pellets. BZY20 pellets with high relative density of ~94% were fabricated with a final sintering temperature of 1500 °C (200 °C lower than the traditional sintering temperature). A comparison with BZY20 control samples indicated that the proper amount of BaCO 3 introduced on the BZY20 particle surface and the high green density achieved by cold sintering pretreatment were the main drivers for lowering the sintering temperature. The electrical conductivity measurement by electrochemical impedance spectroscopy showed that the as-prepared BZY20 pellets have a proton conductivity comparable to the state-of-the-art values. The cold sintering pretreatment outlined in this work has the potential to lower the sintering temperatures for similar types of protonic ceramic materials under consideration for a wide range of energy conversion and storage applications.
The Impact of Surface Structure Transformations on the Performance of Li-Excess Cation-Disordered Rocksalt Cathodes
Not Available
Spark Plasma Sintering of Fuel Cermets for Nuclear Reactor Applications
The feasibility of the fabrication of tungsten based nuclear fuel cermets via Spark Plasma Sintering (SPS) is investigated in this work. CeO2 is used to simulate fuel loadings of UO2 or Mixed-Oxide (MOX) fuels within tungsten-based cermets due to the similar properties of these materials. This study shows that after a short time sintering, greater than 90 % density can be achieved, which is suitable to possess good strength as well as the ability to contain fission products. The mechanical properties and the densities of the samples are also investigated as functions of the applied pressures during the sintering.
Biomass Torrefaction Process Review and Moving Bed Torrefaction System Model Development
Torrefaction is currently developing as an important preprocessing step to improve the quality of biomass in terms of physical properties, and proximate and ultimate composition. Torrefaction is a slow heating of biomass in an inert or reduced environment to a maximum temperature of 300°C. Torrefaction can also be defined as a group of products resulting from the partially controlled and isothermal pyrolysis of biomass occurring in a temperature range of 200-230°C and 270-280°C. Thus, the process can also be called a mild pyrolysis as it occurs at the lower temperature range of the pyrolysis process. At the end of the torrefaction process, a solid uniform product with lower moisture content and higher energy content than raw biomass is produced. Most of the smoke-producing compounds and other volatiles are removed during torrefaction, producing a final product that will have a lower mass but a higher heating value. An important aspect of research is to establish a degree of torrefaction where gains in heating value offset the loss of mass. There is a lack of literature on torrefaction reactor designs and a design sheet for estimating the dimensions of the torrefier based on capacity. This study includes (a) conducting a detailed review on the torrefaction of biomass in terms of understanding the process, product properties, off-gas compositions, and methods used, and (b) to design a moving bed torrefier, taking into account the basic fundamental heat and mass transfer calculations. Specific objectives include calculating the dimensions like diameter and height of the moving packed bed for different capacities, designing the heat loads and gas flow rates, and developing an interactive excel sheet where the user can define design specifications. In this report, 25-1000 kg/hr are used in equations for the design of the torrefier, examples of calculations, and specifications for the torrefier.
Feedstock Supply System Design and Economics for Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels
The U.S. Department of Energy promotes the production of a range of liquid fuels and fuel blendstocks from lignocellulosic biomass feedstocks by funding fundamental and applied research that advances the state of technology in biomass collection, conversion, and sustainability. As part of its involvement in this program, the Idaho National Laboratory (INL) investigates the feedstock logistics economics and sustainability of these fuels. Between 2000 and 2012, INL conducted a campaign to quantify the economics and sustainability of moving biomass from standing in the field or stand to the throat of the biomass conversion process. The goal of this program was to establish the current costs based on conventional equipment and processes, design improvements to the current system, and to mark annual improvements based on higher efficiencies or better designs. The 2012 programmatic target was to demonstrate a delivered biomass logistics cost of 35 USD/dry ton. This goal was successfully achieved in 2012 by implementing field and process demonstration unit-scale data from harvest, collection, storage, preprocessing, handling, and transportation operations into INL’s biomass logistics model. Looking forward to 2017, the programmatic target is to supply biomass to the conversion facilities at a total cost of 80 USD/dry ton and on specification with in-feed requirements. The goal of the 2017 Design Case is to enable expansion of biofuels production beyond highly productive resource areas by breaking the reliance of cost-competitive biofuel production on a single, abundant, low-cost feedstock. If this goal is not achieved, biofuel plants are destined to be small and/or clustered in select regions of the country that have a lock on low-cost feedstock. To put the 2017 cost target into perspective of past accomplishments of the cellulosic ethanol pathway, the 80 USD target encompasses total delivered feedstock cost, including both grower payment and logistics costs, while meeting all conversion in-feed quality targets. The 2012 35 USD programmatic target included only logistics costs with a limited focus on biomass quality
Investigating the Dynamic Compaction Behavior of Brittle Powders
The compression of porous materials to full density is a complex physical and mechanical process. Modeling efforts to capture the compaction behavior of distended solids (e.g., porous materials or powders) have produced a variety of compaction models, each functionalized to address specific compaction mechanisms. Of the available models, those suited for high-strain-rate deformation associated with shock loading have generally been developed for ductile materials. Compaction models for brittle materials have only been developed for quasistatic loading conditions. No predictive models currently exist that successfully capture the physical processes and mechanics for shock compaction of brittle distended materials, such as sand and oxide powders. The primary hindrance in producing a dynamic compaction model for brittle distended materials is the lack of availability of high-fidelity, high-precision shock compaction data for validation. The proposed work is aimed at alleviating this issue by developing a high-precision testing method in combination with high-fidelity analysis methods to accurately and precisely determine the shocked state of an ideal test material, ceria powder, under uniaxial strain dynamic compaction. The measured shock compaction data from these brittle powder experiments is then used in initial computations to design a cylindrically converging shock compaction experiment within situ time-resolved shocked density measurements, employing proton radiography. The preliminary experimental and computational results obtained from these uniaxial strain dynamic compaction and cylindrically converging shock compaction experiments are presented. An experimental and computational path forwards to predictive model development is then proposed.
Lignetics CRADA closeout report
Lignetics is one of the leading domestic producers of wood pellet fuels used for domestic heating. The company also produces pellets for other applications including animal bedding. The primary feedstock used for the production of Lignetics products is woody biomass. To improve the economics of pellet production, Lignetics is evaluating advanced preprocessing technologies developed by researchers at INL. In the proposed project, INL and Lignetics will work collaboratively to assess the feasibility of integrating INL’s advanced preprocessing technologies (fractional milling, high moisture pelleting and low temperature drying) in Lignetics production facilities. The successful completion of the project relies on the integration of the fractional milling and high moisture pelleting (HMP) process and low temperature drying to improve the economics of woody biomass pellet production for use in biofuel and bioproduct applications. In the HMP process, the biomass loses some moisture during compression and extrusion through the pellet die due frictional heat developed. Also, as pellets have a definite size and shape, they can be further dried in low temperature grain or belt dryers. Belt dryers are better suited to take advantage of low-grade and waste heat because they operate at lower temperatures than rotary dryers (Tumuluru et al.) Rotary dryers, for example, typically require inlet temperatures of 260°C, but more optimally operate around 400°C. In contrast, the inlet temperature of a belt dryer, such as a commercially available vacuum dryer, can be as low as 10°C above the ambient temperature, although more typically they operate at higher temperatures, between 90°C and 200°C. Because of their lower temperature operation, fire hazards and emissions to the air are lower for belt dryers in addition to reducing drying and overall pelleting costs, INL’s technology also has potential to reduce emissions at Lignetics facilities.
Biomass Torrefaction Process Review and Moving Bed Torrefaction System Model Development
Torrefaction is currently developing as an important preprocessing step to improve the quality of biomass in terms of physical properties, and proximate and ultimate composition. Torrefaction is a slow heating of biomass in an inert or reduced environment to a maximum temperature of 300°C. Torrefaction can also be defined as a group of products resulting from the partially controlled and isothermal pyrolysis of biomass occurring in a temperature range of 200–230ºC and 270–280ºC. Thus, the process can also be called a mild pyrolysis as it occurs at the lower temperature range of the pyrolysis process. At the end of the torrefaction process, a solid uniform product with lower moisture content and higher energy content than raw biomass is produced. Most of the smoke-producing compounds and other volatiles are removed during torrefaction, producing a final product that will have a lower mass but a higher heating value. An important aspect of research is to establish a degree of torrefaction where gains in heating value offset the loss of mass. There is a lack of literature on torrefaction reactor designs and a design sheet for estimating the dimensions of the torrefier based on capacity. This study includes a) conducting a detailed review on the torrefaction of biomass in terms of understanding the process, product properties, off-gas compositions, and methods used, and b) to design a moving bed torrefier, taking into account the basic fundamental heat and mass transfer calculations. Specific objectives include calculating the dimensions like diameter and height of the moving packed bed for different capacities, designing the heat loads and gas flow rates, and developing an interactive excel sheet where the user can define design specifications. In this report, 25–1000 kg/hr are used in equations for the design of the torrefier, examples of calculations, and specifications for the torrefier.
High Char Yield and Flowable Preceramic Resin Enabled with the Monomer Functionalized SiC Particle
Ceramic matrix composites (CMCs) are used in diverse high temperature applications; however, manufacturing CMCs is highly time consuming and costly. We address this challenge by introducing a methodology for fabricating CMCs using an innovative composite preceramic resin. This composite resin contains 40% mass loading of SiC particles, which are chemically functionalized with a resin monomer. The functionalization facilitates a homogenous dispersion of SiC particles within the resin matrix, resulting in high char yield (83.6%) and enhanced impregnation efficiency through reduced melt viscosity, ~10 Pa.s for relevant shear rates. This breakthrough represents a significant stride towards developing a more economically viable and efficient manufacturing process for CMCs.
Effect of Pelleting on the recalcitrance and bioco
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Preliminary Considerations for Microwave Consolidation/Sintering of Lunar Regolith Simulant
As NASA prepares to establish permanent habitats on the Moon, a significant first step is to be able to land multiple times in the same area. As was consistently shown during the Apollo program, the very fine granular structure of the lunar regolith (the Moon’s “soil”)poses significant physical and health challenges [1]. One of the most concerning is the hyper-velocity lunar surface ejecta that results from the engine exhaust that exits the rocket as it lands and takes off [2]. It has been determined that to mitigate this, the regolith must be consolidated.
Reduction of Porosity to Increase Critical Current Density in Bi-2212 Superconducting Wire
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Biomass Research Program
INL's mission is to achieve DOE's vision of supplying high-quality raw biomass; preprocessing biomass into advanced bioenergy feedstocks; and delivering bioenergy commodities to biorefineries. You can learn more about research like this at the lab's facebook site http://www.facebook.com/idahonationallaboratory.