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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 181 records · Page 10

Using Project Complexity Determinations to Establish Required Levels of Project Rigor

The concepts discussed in this paper 1) focus on using technical competencies and skills in making objective determinations regarding project complexity based on objective scoring criteria and 2) then using the complexity determinations to establish the level of rigor required in initiating, planning, executing, monitoring and controlling, and closing projects to maximize process efficiency. This paper presents a project complexity analysis methodology for defining the levels of project management process rigor a project team needs to employ to maximize project delivery efficiencies without compromising quality and performance. Methods for making project complexity determinations based on project lifecycle size, duration, organizational complexity, requirements, technology readiness, risk, and visibility are discussed. The paper correlates the levels of rigor needed by project management process groups given the determined level of project complexity. Next, the paper presents a graded approach to defining extent of team formation, planning documentation rigor, stakeholder communication rigor, requirements management rigor, acquisition planning, risk management, executing, and monitoring and controlling rigor dependent on project complexity determinations. Methods for integrating and aligning the project complexity determination methods into existing project management procedures and processes are also discussed as well as methods for training personnel in the use of the method and facilitating and monitoring effectiveness of implementation within an organization in which project delivery is a mission focus.

complexity, project, determination, management, tr↗

Accelerating catalytic advancements through the precision of high-throughput experiments & calculations

The growing demand for energy-efficient processes to support a sustainable future drives the need for research to rapidly explore chemical and material space through accelerated catalyst discovery initiatives. Recent breakthroughs in high-throughput experimental and computational methods are transforming the catalysis field, surpassing traditional approaches to manipulating variables in catalytic processes. Key advancements in innovation include the integration of machine learning for efficient catalyst screening, high-throughput experimentation, data-driven methodologies employing comprehensive databases, and in situ and in operando techniques for realistic observations. This progress has undoubtedly been intertwined with a collaborative framework across disciplines, reshaping catalyst discovery methods in both industry and academia. This Opinion article presents a multifaceted perspective from coauthors with expertise spanning various stages of the Technology Readiness Level spectrum, highlighting both opportunities and persistent challenges in integrating computational and experimental approaches in catalysis. These challenges span from obtaining high-quality experimental data, scaling simulations to industrially relevant materials and process conditions to navigating the complexity and predictive accuracy of computational models.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Science Capsule - Capturing the Data Life Cycle

The data generated from scientific workflows often become unusable due to the lack or incompleteness of information required for processing and analyzing the data. Reproducibility of scientific data and workflows facilitates efficient processing and analyses. A key to enabling reproducibility is to capture the end-to-end workflow life cycle, and any contextual metadata and provenance.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗

Comparison of Commercial, State-of-the-Art, Fossil-Based Ammonia Production

This NETL report provides a comprehensive techno-economic analysis of current, state-of-the-art, fossil-based ammonia production processes, explicitly utilizing natural gas as the feedstock. The study thoroughly investigates three distinct configurations: conventional Steam Methane Reforming (SMR) without carbon capture, SMR integrated with carbon capture and storage (CCS), and Autothermal Reforming (ATR) also with CCS. The analysis incorporates detailed equipment cost accounting as part of its methodology. The primary objective is to meticulously evaluate the cost and performance of these established and emerging technological pathways, considering factors such as capital expenditures, operational costs, and energy consumption. While the report acknowledges and quantifies environmental impacts, its central focus remains on the economic and technical feasibility of each process design employing these current technologies. The analysis provides a direct comparison of the Levelized Cost of Ammonia (LCOA) for each pathway, revealing how the integration of CCS within these state-of-the-art systems impacts the overall production cost. The ATR+CCS configuration, representing an advanced approach, emerged with a slightly more favorable LCOA compared to SMR+CCS. This benefit was attributed to its inherent process efficiencies, high carbon capture rates, and economy of scale advantages. The report details the energy consumption profiles for each case, including metrics like net energy consumption and thermal efficiency, which are critical for assessing the performance of these contemporary industrial processes. Sensitivity analyses further explore how variables such as natural gas price, capital costs, and capacity factors influence the LCOA across all scenarios, offering critical insights into the economic robustness and scalability of these current ammonia production technologies.

03 NATURAL GAS↗

Vertical Advection Effects on Hyper-accretion Disks and Potential Link between Gamma-Ray Bursts and Kilonovae

Recent simulations on super-Eddington accretion flows have shown that, apart from the diffusion process, the vertical advection based on magnetic buoyancy can be a more efficient process to release the trapped photons in the optically thick disk. As a consequence, the radiative luminosity from the accretion disk can be far beyond the Eddington value. Following this spirit, we revisit the structure and radiation of hyper-accretion disks with mass accretion rates in the range of 10{sup −3}∼10 M{sub ⊙} s{sup −1}. Our results show that, due to the strong cooling through the vertical advection, the disk temperature becomes lower than that in the classic model without the vertical advection process, and therefore the neutrino luminosity from the disk is lower. On the other hand, the gamma-ray photons released through the vertical advection can be extremely super-Eddington. We argue that the large amount of escaped gamma-ray photons may have more significant contribution to the primordial fireball than the neutrino annihilation, and may hint at a link between gamma-ray bursts and kilonovae in the black hole hyper-accretion scenario.

79 ASTRONOMY AND ASTROPHYSICS↗

Process Control and Energy Efficiency

We review the impact of control systems and strategies on the energy efficiency of chemical processes. We show that, in many ways, good control performance is a necessary but not sufficient condition for energy efficiency. The direct effect of process control on energy efficiency is manyfold: Reducing output variability allows for operating chemical plants closer to their limits, where the energy/economic optima typically lie. Further, good control enables novel, transient operating strategies, such as conversion smoothing and demand response. Indirectly, control systems are key to the implementation and operation of more energy-efficient plant designs, as dictated by the process integration and intensification paradigms. Our conclusions are supported with references to numerous examples from the literature.

42 ENGINEERING↗

Process sensitivity studies of the Westinghouse sulfur cycle for hydrogen generation

The effect of variations of acid concentration, pressure, and temperature on the thermal process efficiency of the Westinghouse sulfur cycle was examined using the HYDRGN program. Modifications to the original program were made to duplicate the process flowsheet and take into account combined cycle heat-to-work efficiencies for electrochemical work requirements, aqueous solutions, and heat-of-mixing effects. A total of 125 process variations were considered (acid concentration: 50-90 w/o; pressure: 15-750 psia; temperature: 922K - 1366K). The methods of analysis, results, and conclusions are presented.

Carty, R. H.↗

In-situ anodic precipitation process for highly efficient separation of aluminum alloys

Electrorefining process has been widely used to separate and purify metals, but it is limited by deposition potential of the metal itself. Here we report in-situ anodic precipitation (IAP), a modified electrorefining process, to purify aluminium from contaminants that are more reactive. During IAP, the target metals that are more cathodic than aluminium are oxidized at the anode and forced to precipitate out in a low oxidation state. This strategy is fundamentally based on different solubilities of target metal chlorides in the NaAlCl4 molten salt rather than deposition potential of metals. The results suggest that IAP is able to efficiently and simply separate components of aluminum alloys with fast kinetics and high recovery yields, and it is also a valuable synthetic approach for metal chlorides in low oxidation states.

36 MATERIALS SCIENCE↗

Dynamic analysis of concentrated solar supercritical CO2-based power generation closed-loop cycle

Here, the dynamic behavior of a concentrated solar power (CSP) supercritical CO 2 cycle is studied under different seasonal conditions. The system analyzed is composed of a central receiver, hot and cold thermal energy storage units, a heat exchanger, a recuperator, and multi-stage compression-expansion subsystems with intercoolers and reheaters between compressors and turbines respectively. Energy models for each component of the system are developed in order to optimize operating and design parameters such as mass flow rate, intermediate pressures and the effective area of the recuperator to lead to maximum efficiency. Our results show that the parametric optimization leads the system to a process efficiency of about 21 % and a maximum power output close to 1.5 MW. The thermal energy storage allows the system to operate for several hours after sunset. This operating time is approximately increased from 220 to 480 minutes after optimization. The hot and cold thermal energy storage also lessens the temperature fluctuations by providing smooth changes of temperatures at the turbines and compressors inlets. Our results indicate that concentrated solar systems using supercritical CO 2 could be a viable alternative to satisfying energy needs in desert areas with scarce water and fossil fuel resources.

14 SOLAR ENERGY↗

MAPPRAISER: A massively parallel map-making framework for multi-kilo pixel CMB experiments

Forthcoming cosmic microwave background (CMB) polarized anisotropy experiments have the potential to revolutionize our understanding of the Universe and fundamental physics. The sought-after, tale-telling signatures will be however distributed over voluminous data sets which these experiments will collect. These data sets will need to be efficiently processed and unwanted contributions due to astrophysical, environmental, and instrumental effects characterized and efficiently mitigated in order to uncover the signatures. This poses a significant challenge to data analysis methods, techniques, and software tools which will not only have to be able to cope with huge volumes of data but to do so with unprecedented precision driven by the demanding science goals posed for the new experiments. A keystone of efficient CMB data analysis is solvers of very large linear systems of equations. Such systems appear in very diverse contexts throughout CMB data analysis pipelines, however they typically display similar algebraic structures and can therefore be solved using similar numerical techniques. Linear systems arising in the so-called map-making problem are one of the most prominent and common ones. In this work we present a massively parallel, flexible and extensible framework, comprised of a numerical library, MIDAPACK, and a high level code, MAPPRAISER, which provide tools for solving efficiently such systems. Here, the framework implements iterative solvers based on conjugate gradient techniques: enlarged and preconditioned using different preconditioners. We demonstrate the framework on simulated examples reflecting basic characteristics of the forthcoming data sets issued by ground-based and satellite-borne instruments, executing it on as many as 16,384 compute cores. The software is developed as an open source project freely available to the community at: https://github.com/B3Dcmb/midapack.

79 ASTRONOMY AND ASTROPHYSICS↗

A Reactor Scale-Up Methodology from Lab-Scale to Pilot-Scale Operations: Numerical Modeling of THFA Dehydration to DHP in Packed-Bed Reactors

This manuscript discusses developing a model-based scale-up methodology for a successful technology transfer of gas-phase catalytic reactors from a lab-scale to a pilot-scale operation. The manuscript demonstrates the methodology for gas-phase dehydration of tetrahydrofurfuryl alcohol (THFA) to dihydropyran (DHP) process over commercial Al 2 O 3 catalysts. A two-dimensional reactor model was developed using COMSOL Multiphysics 6.1 software. The model solves heat and mass transport equations in bed-scale and particle scales simultaneously. This powerful feature enables accurate prediction of the heat and mass transfer limitations in pilot-scale reactors, if any exists. Further, the model uses isothermal lab-scale experimental data to derive and validate the reaction chemistry, flow fields and boundary conditions. The model was then scaled-up to project conversion, selectivity, yield and formation rate of DHP in a pilot-scale reactor. The results highlight the complex nature of chemistry, heat, and mass transfer effects in lab-scale and pilot-scale reactors. The model results inform the possible operational limitations of the pilot-scale reactor and design strategies to improve process efficiency. Although the scale-up approach is explained through the THFA dehydration process, the methodology is applicable to any catalytic packed-bed reactor models for a successful process scale-up.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Catalyst design for enhanced sustainability through fundamental surface chemistry

Decreasing energy consumption in the production of platform chemicals is necessary to improve the sustainability of the chemical industry, which is the largest consumer of delivered energy. The majority of industrial chemical transformations rely on catalysts, and therefore designing new materials that catalyse the production of important chemicals via more selective and energy-efficient processes is a promising pathway to reducing energy use by the chemical industry. Efficiently designing new catalysts benefits from an integrated approach involving fundamental experimental studies and theoretical modelling in addition to evaluation of materials under working catalytic conditions. In this paper, we outline this approach in the context of a particular catalyst—nanoporous gold (npAu)—which is an unsupported, dilute AgAu alloy catalyst that is highly active for the selective oxidative transformation of alcohols. Fundamental surface science studies on Au single crystals and AgAu thin-film alloys in combination with theoretical modelling were used to identify the principles which define the reactivity of npAu and subsequently enabled prediction of new reactive pathways on this material. Specifically, weak van der Waals interactions are key to the selectivity of Au materials, including npAu. Finally, we also briefly describe other systems in which this integrated approach was applied.

36 MATERIALS SCIENCE↗

Advanced sorbents for modular oxygen production for REMS gasifiers

Under a DOE funded effort, Thermosolv LLC has been developing a sorbent-based oxygen production technology for gasification and oxy-combustion applications. The sorbents utilize oxygen-storage properties of certain perovskites to (1) selectively adsorb oxygen at moderate temperature from compressed air and (2) release the adsorbed oxygen into a vacuum or a sweep gas such as CO2 and/or steam. Through cyclic operations of multiple sorbent beds such a process can be made continuous. Pressure drop across the sorbent bed and other similar design considerations dictate that the sorbent be in the form of a high surface-area-to-volume pellet and yet still possess sufficient crush strength and integrity. Process efficiency is determined by the sorption and desorption kinetics and sorbent capacity. Typical process involves cycle times in the order of 100 seconds, a time too short to fully utilize the full volume of the sorbent and the sorption capacity of the sorbent pellets. As a part of this project, Thermosolv LLC undertook the development of oxygen sorbents as a high-surface area supported sorbent on a light-weight inert support to (1) reduce the cost, (2) increase the productivity, and (3) reduce the overall weight of the reactor. Using a previously developed perovskite (LSCF 1991) with its well-characterized performance, composite sorbent pellets each consisting of an inert core coated by a thin layer of the functional perovskite material were produced. Several low-density, inexpensive inert solids supports in the 1/8”-1/4” size were selected to keep the pressure drop across the sorbent bed in the acceptable range. A number of commercial technologies including spray coating, dip coating, incipient impregnation of porous substrate followed by thermal annealing at various temperatures and duration were employed and tested to produce robust composite supported sorbent pellets. A sense of optimum coating thickness was developed by testing sorbent pellets of various increasing diameter pellets. LSCF-1991extrudates ranging in size from 1/32” to 3/16” were tested in a TGA and in a fixed-bed pressure swing test set-up for sorption/desorption cycles of interest. The data show that for the operational conditions of interest the coating thickness for a supported sorbent pellet needs to be approximately 1/32” (about 0.8 mm). Subsequent work thereby concentrated on developing composite pellets of various substrates, shapes and sizes with coating layer of about this size range. Candidate support materials were chosen based on cost, inertness, mechanical strength, thermal expansion and chemical stability with sorbent material, and in a size range to give an acceptable pressure drop in fixed-bad reactor configurations. Coating application methods used for application of the sorbent onto the support included precipitation, spray coating and dip coating from sorbent slurries and sol gels. For all coated supports where we could successfully apply a uniform coating of desired thickness with an acceptable handling performance in terms of exfoliation, TGA-based cyclic sorption/desorption testing was performed to determine cycling capacity of oxygen. Among nearly twenty different support materials tested, best adhesion performance was obtained from stainless saddle supports. In the bench-scale fixed-bad tests stainless steel saddle support composite pellets with a coating thickness in the 0.6 mm or so range, the composite sorbent pellet performance approached up to 95% of that of the 2 mm parent material pellets. In a parallel approach to reducing the cost of the sorbent, alternate sorbent formulations replacing/reducing the amount of cobalt in the LSCF family were also investigated. Successful formulations that could match the performance of LSCF 1991 were identified based on TGA cyclic tests as LSCF 1919 and LSF 1910. In the range of operational envelop of cycle times and other relevant process operating conditions, the reduced Co formulations showed comparable performance in the bench-scale fixed-bad cyclic operations. As a part of this project, we also attempted substitution of La and Sr with Ca and Ba, and Co with Mn, Ni and Cu with little success, but the overall project goal of reducing sorbent cost in terms of raw material and manufacturing expenses was successful.

01 COAL, LIGNITE, AND PEAT↗

Low cost processes for fabricating silicon solar cells

Solar cell fabrication processes, in particular junction formation and metallization, are evaluated in terms of cell efficiencies, process yields, module packing factors, and energy cost effectiveness. It is shown that for junction formation, the diffusion processes provide a relatively low-cost approach. The costs per unit cell area can be further reduced by increased wafer area and mechanized wafer handling. The costs for a large number of metallization processes, excluding the costs of the metal, are roughly comparable. However, their varying influence on cell performance leads to a significant spread in the allowable process costs.

Goldman, H.↗

Electron Beam Freeform Fabrication in the Space Environment

The influence of reduced gravitational forces (in space and on the lunar or Martian surfaces) on manufacturing processes must be understood for effective fabrication and repair of structures and replacement parts during long duration space missions. The electron beam freeform fabrication (EBF3) process uses an electron beam and wire to fabricate metallic structures. The process efficiencies of the electron beam and the solid wire feedstock make the EBF3 process attractive for use in-space. This paper will describe the suitability of the EBF3 process in the space environment and will highlight preliminary testing of the EBF3 process in a zero-gravity environment.

Hafley, Robert A.↗

Microwave-assisted delignification for improved cellulose production

This study aims to develop microwave (MW) technologies to improve the paper pulping process, decreasing both chemical and thermal energy requirements. The overall objective is to explore an efficient process that aids in the delignification of paper pulp, reducing energy needs and chemical intensity. The experimental variables evaluated during the MW-assisted digestion process include formic acid concentration, time, temperature, digestion cycles, and the formic acid to paper ratio. This research investigates the potential of MW technology to create a more sustainable and efficient cellulose production method.

microwave heating↗

Assessment of Energy Efficiency Improvement in the United States Petroleum Refining Industry

Adoption of efficient process technologies is an important approach to reducing CO 2 emissions, in particular those associated with combustion. In many cases, implementing energy efficiency measures is among the most cost-effective approaches that any refiner can take, improving productivity while reducing emissions. Therefore, careful analysis of the options and costs associated with efficiency measures is required to establish sound carbon policies addressing global climate change, and is the primary focus of LBNL’s current petroleum refining sector analysis for the U.S. Environmental Protection Agency. The analysis is aimed at identifying energy efficiency-related measures and developing energy abatement supply curves and CO 2 emissions reduction potential for the U.S. refining industry. A refinery model has been developed for this purpose that is a notional aggregation of the U.S. petroleum refining sector. It consists of twelve processing units and account s for the additional energy requirements from steam generation, hydrogen production and water utilities required by each of the twelve processing units. The model is carbon and energy balanced such that crud e oil inputs and major refinery sector outputs (fuels) are benchmarked to 2010 data. Estimates of the current penetration for the identified energy efficiency measures benchmark the energy requirements to those reported in U.S. DOE 2010 data. The remaining energy efficiency potential for each of the measures is estimated and compared to U.S. DOE fuel prices resulting in estimates of cost- effective energy efficiency opportunities for each of the twelve major processes. A combined cost of conserved energy supply curve is also presented along with the CO 2 emissions abatement opportunities that exist in the U.S. petroleum refinery sector. Roughly 1,200 PJ per year of primary fuels savings and close to 500 GWh per y ear of electricity savings are potentially cost-effective given U.S. DOE fuel price forecasts. This represents roughly 70 million metric tonnes of CO 2 emission reductions assuming 2010 emissions factor for grid electricity. Energy efficiency measures resulting in an additional 400 PJ per year of primary fuels savings and close to 1,700 GWh per year of electricity savings, and an associated 24 million metric tonnes of CO 2 emission reductions are not cost-effective given the same assumption with respect to fuel prices and electricity emissions factors. Compared to the modeled energy requirements for the U.S. petroleum refining sector, the cost effective potential represents a 40% reduction in fuel consumption and a 2% reduction in electricity consumption. The non-cost-effective potential represents an additional 13% reduction in fuel consumption and an additional 7% reduction in electricity consumption. The relative energy reduction potentials are mu ch higher for fuel consumption than electricity consumption largely in part because fuel is the primary energy consumption type in the refineries. Moreover, many cost effective fuel savings measures would increase electricity consumption. The model also has the potential to be used to examine the costs and benefits of the other CO 2 mitigation options, such as combined heat and power (CHP), carbon capture, and the potential introduction of biomass feedstocks. However, these options are not addressed in this report as this report is focused on developing the modeling methodology and assessing fuels savings measures. These opportunities to further reduce refinery sector CO 2 emissions and are recommended for further research and analysis.

25 ENERGY STORAGE↗

Janus Membranes: Creating Asymmetry for Energy Efficiency

Membranes are recognized as a key component in many environment and energy–related applications, but conventional membranes are challenged to satisfy the growing demand for ever more energy–efficient processes. Janus membranes, a novel class with asymmetric properties on each side, have recently emerged and represent enticing opportunities to address this challenge. With an inner driving force arising from their asymmetric configuration, Janus membranes are appealing for enhancing energy efficiency in a variety of membrane processes by promoting the desired transport. Furthermore, the fundamental principles to prepare Janus membranes with asymmetric surface wettability and charges are summarized, and how they work in conventional and unconventional membrane processes is demonstrated.

36 MATERIALS SCIENCE↗