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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 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

The Effect of the Main Injector Ramp on the Recycler

The Recycler and Main Injector are part of the Fermilab Accelerator complex used to deliver a high power proton beam. Both machines share the same enclosure with the Recycler mounted 6 ft above the Main Injector. The Main Injector accelerates beam from 8 GeV to 120 GeV. While the majority of the Recycler has mu metal shielding, the effect of the Main Injector ramp is still significant and can affect both the tunes and the orbit. In this paper, we detail the size of these effects.

43 PARTICLE ACCELERATORS↗
DOE OSTI2026

Dynamic aperture studies at the Fermilab recycler ring

As part of the Proton Improvement Plan II (PIP-II), Fermilab aims to increase beam intensity delivered to neutrino experiments. In this context, higher intensity injection into the Recycler Ring enhances space charge effects, pushing operations closer to third-order resonances. These resonances reduce the Dynamic Aperture (DA), leading to increased beam loss. This study presents simulations of DA as a function of tune in the Recycler Ring, incorporating chaos indicators such as the Reversibility Error Method (REM) and Frequency Map Analysis (FMA). The effectiveness of existing resonance mitigation strategies is evaluated by quantifying their ability to delay DA degradation. Additionally, the study examines how space charge detuning and DA limitations dictate viable operational tune points for the Recycler Ring.

Gonzalez-Ortiz, Cristhian [Fermilab]↗
DOE OSTI2021

Modeling of Glycolate Destruction in the Recycle Collection Tank

The Savannah River Site’s DWPF is being upgraded with the introduction of the NG flowsheet. Glycolic acid has been shown to be a superior alternative to formic acid for sludge processing. The new flowsheet improves or maintains necessary parameters such as 1) reduction of mercury, 2) adjustment of feed rheology, 3) pH stability, and 4) adjustment of melter oxidation/reduction potential. Further, the use of glycolic acid virtually eliminates the potential for catalytic hydrogen generation in DWPF processing DWPF process condensates are collected and returned to the Savannah River Site (SRS) CSTF. The RCT collects off-gas condensate during chemical processing, vitrification, and other unit operations performed in DWPF and is the singular return vessel delivering recycle effluent back to CSTF. Each batch of recycle will have a small amount of glycolate from chemical processing and melter off-gas condensates. To avoid potential flammability issues due to thermolysis of glycolate in the CSTF, Savannah River National Laboratory (SRNL) provided to Savannah River Remediation (SRR) at their request a Task Technical and Quality Assurance Plan (TTQAP) to quantify and mitigate glycolate returns via DWPF’s recycle stream. The request included testing of a process to oxidize glycolate and other organic species that are responsible for hydrogen generation from thermolysis. Following that work SRR provided a Task Technical Request (TTR) that requested process modeling. In 2021 a TTQAP was issued to cover the modeling work. Modeling draws data from laboratory scale studies using chemical simulants and radioactive waste samples. Chemical kinetic modeling was performed to evaluate the feasibility of using sodium permanganate to destroy glycolate in the RCT. The results from the laboratory studies were summarized in a series of reports. Reference 9 is a report of lab scale processing of actual DWPF Slurry Mix Evaporate Condensate Tank (SMECT) and Offgas Condensate Tank (OGCT) samples in the SRNL Shielded Cells. Tests at caustic conditions demonstrated sodium permanganate was effective in converting glycolate to oxalate, and permanganate (Mn 7+ ) is reduced to manganate (Mn 6+ ) with no significant formation of carbon dioxide or carbonate. Equation (1) was found to best describe the observed reaction of glycolate with permanganate under nominal (60 to 145 mg/L in RCT) glycolate entrainment conditions.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2023

Advanced Energy Manufacturing and Recycling Grant Readiness Technical Assistance Program [Slides]

The U.S. Department of Energy's Office of Manufacturing and Energy Supply Chains (MESC) has launched a new technical assistance program, administered by NREL, in support of prospective applicants to the Advanced Energy Manufacturing and Recycling Grant Program. The competitive technical assistance program will help small- and medium-sized manufacturers understand the requirements of the Advanced Energy Manufacturing and Recycling Grant Program and prepare for future applications. Such applications must propose a project to build, retrofit, or expand facilities in coal communities for producing or recycling goods used to support clean energy supply chains. This presentation is for an informational webinar on Wednesday, April 26, 2023.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2025

Dynamic Aperture Studies at the Fermilab Recycler Ring

As part of the Proton Improvement Plan II (PIP-II), Fermilab aims to increase beam intensity delivered to neutrino experiments. In this context, higher intensity injection into the Recycler Ring enhances space charge effects, pushing operations closer to third-order resonances. These resonances reduce the Dynamic Aperture (DA), leading to increased beam loss. This study presents simulations of DA as a function of tune in the Recycler Ring, incorporating chaos indicators such as the Reversibility Error Method (REM). The effectiveness of existing resonance mitigation strategies is evaluated by quantifying their ability to delay DA degradation. Additionally, the study examines how space charge detuning and DA limitations dictate viable operational tune points for the Recycler Ring.

Gonzalez-Ortiz, Cristhian Eduardo [Fermilab]↗
DOE OSTI2026

Advanced Facility Design and AI/ML Enabled Safeguards to Establish Secure, Economical Recycling of Fast Reactor Fuels (Final Scientific/Technical Report)

The project, "Advanced Facility Design and AI/ML Enabled Safeguards to Establish Secure, Economical Recycling of Fast Reactor Fuels," represents a significant advancement in nuclear fuel recycling technology. It integrates cutting-edge multimodal sensor fusion, machine learning (ML), and digital twin (DT) technologies to address challenges in material safeguarding, process optimization, and regulatory compliance for pyroprocessing facilities. This research has significantly enhanced the understanding of pyrochemical fuel recycling processes by developing innovative tools and methodologies. The Multimodal Safeguards Monitoring Unit (MSMU) combines electroanalytical techniques, Raman spectroscopy, and differential thermal analysis (DTA) to enable high-fidelity, near-real-time material accountancy measurements. Machine learning techniques, such as Long Short-Term Memory (LSTM) autoencoders, are utilized to detect anomalies in material balances and sensor data, improving the reliability of safeguards monitoring. Additionally, digital twin technology has been established to provide real-time system-level monitoring and diagnostics, integrating physics-based models with sensor data to optimize process safety and efficiency.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2025

Machine Learning-Based Process Control for Injection Molding of Recycled Polypropylene

The increased interest in artificial intelligence in manufacturing has driven the adoption of machine learning to optimize processes and improve efficiency. A key challenge in injection molding is the variability of recycled materials, which affects part quality and processing stability. This study presents a novel closed-loop process control approach for injection molding, leveraging machine learning to adaptively predict processing inputs and quality outcomes. The methodology was tested on five blends of recycled polypropylene (rPP), using artificial neural networks (ANNs), linear regression, and polynomial regression to model the relationships between material properties and process parameters. The dataset was split 80/20 into training and testing sets. The ANN model was implemented using TensorFlow and Keras, with six hidden layers of 32 neurons per layer, ReLU activation, and an Adam optimizer. Empirical tuning and early stopping were used to optimize performance and prevent overfitting. Predictions were evaluated based on mean absolute error (MAE), mean squared error (MSE), and percentage error. The results showed that yield stress, ultimate elongation, and part weight were accurately predicted within a 5% error for linear and polynomial regression models and within a 10% error for the ANN. However, modulus predictions were less reliable, with errors of ~11% for ANN and linear regression and ~40% for polynomial regression, reflecting the inherent variability of this property in rPP blends. Predictions of processing inputs had errors ranging from 3% to 25%, depending on the model and response variable. No single modeling approach was consistently superior across all responses, highlighting the complexity of the relationship between material properties, process parameters, and quality metrics. Overall, the work demonstrates that closed-loop process control, powered by machine learning, can effectively predict key quality parameters in injection molding of recycled materials. The proposed approach can improve process stability and material utilization, facilitating increased adoption of sustainable materials.

Krantz, Joshua↗
NASA NTRS1985

The relation between the age of the subconducting slab and the recycling of sediments into the mantle

The recycling of sediments into the mantle has become an important issue because recent papers have suggested that the geochemical inverse models of the evolution of radiogenic isotope abundances over the history of the Earth have nonunique solutions. Both the recycling of continent-derived sediments into the mantle and mixing in the mantle could produce similar geochemical effects in the mean isotopic ratios of new igneous material emplaced in continents. Recent models of Archaean heat flow and of plate tectonics during early Earth history have demonstrated that higher internal heat production of the early Earth was mainly dissipated through a higher creation rate of oceanic lithosphere. If the seafloor creation rate was higher on the early Earth, then the residence time of any one piece of oceanic lithosphere on the surface would have been shorter. It is possible that a higher rate of recycling of oceanic lithosphere into the mantle could have resulted in some transport of sediment into the mantle.

Abbott, D.↗
NASA NTRS1987

Biomass recycle as a means to improve the energy efficiency of CELSS algal culture systems

Algal cultures can be very rapid and efficient means to generate biomass and regenerate the atmosphere for closed environmental life support systems. However, as in the case of most higher plants, a significant fraction of the biomass produced by most algae cannot be directly converted to a useful food product by standard food technology procedures. This waste biomass will serve as an energy drain on the overall system unless it can be efficiently recycled without a significant loss of its energy content. Experiments are reported in which cultures of the alga Scenedesmus obliquus were grown in the light and at the expense of an added carbon source, which either replaced or supplemented the actinic light. As part of these experiments, hydrolyzed waste biomass from these same algae were tested to determine whether the algae themselves could be made part of the biological recycling process. Results indicate that hydrolyzed algal (and plant) biomass can serve as carbon and energy sources for the growth of these algae, suggesting that the efficiency of the closed system could be significantly improved using this recycling process.

Radmer, R.↗
NASA NTRS1987

An improved external recycle reactor for determining gas-solid reaction kinetics

These improvements in the recycle system effectively eliminate initial concentration variation by two modifications: (1) a vacuum line connection to the recycle loop which permits this loop to be evacuated and then filled with the test gas mixture to slightly above atmospheric pressure; and (2) a bypass line across the reactor which permits the reactor to be held under vacuum while the rest of the recycle loop is filled with test gas. A three-step procedure for bringing the feed gas mixture into contact with the catalyst at time zero is described.

Miller, Irvin M.↗
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.↗
NASA NTRS1993

Continental water recycling and H2(18)-O concentrations

Using a General Circulation Model (GCM) fitted with tracer diagnostics, we examine how continental moisture recycling affects the stable water isotope content of precipitation, focusing on its contribution to the 'noise' in the well-established relationship between temperature and delta O-18. On a global basis, for temperatures between -30 and 15 C, continental recycling explains more than a third of the variability in annual delta O-18 that is not explained by temperature. Recycling appears almost as important as temperature in defining delta O-18 distributions during northern hemisphere summer.

Koster, Randal D.↗
NASA NTRS1997

Update on Chemical Analysis of Recovered Hydrazine Family Fuels for Recycling

The National Aeronautics and Space Administration, Kennedy Space Center, has developed a program to re-use and/or recycle hypergolic propellants recovered from propellant systems. As part of this effort, new techniques were developed to analyze recovered propellants. At the 1996 PDCS, the paper 'Chemical Analysis of Recovered Hydrazine Family Fuels For Recycling' presented analytical techniques used in accordance with KSC specifications which define what recovered propellants are acceptable for recycling. This paper is a follow up to the 1996 paper. Lower detection limits and response linearity were examined for two gas chromatograph methods.

Davis, C. L.↗
NASA NTRS1993

Hydroponic Crop Production using Recycled Nutrients from Inedible Crop Residues

The coupling of plant growth and waste recycling systems is an important step toward the development of bioregenerative life support systems. This research examined the effectiveness of two alternative methods for recycling nutrients from the inedible fraction (residue) of candidate crops in a bioregenerative system as follows: (1) extraction in water, or leaching, and (2) combustion at 550 C, with subsequent reconstitution of the ash in acid. The effectiveness of the different methods was evaluated by (1) comparing the percent recovery of nutrients, and (2) measuring short- and long-term plant growth in hydroponic solutions, based on recycled nutrients.

Garland, Jay L.↗
NASA NTRS1997

Tire Recycling

Cryopolymers, Inc. tapped NASA expertise to improve a process for recycling vehicle tires by converting shredded rubber into products that can be used in asphalt road beds, new tires, hoses, and other products. In conjunction with the Southern Technology Applications Center and Stennis Space Center, NASA expertise in cryogenic fuel-handling needed for launch vehicle and spacecraft operations was called upon to improve the recycling concept. Stennis advised Cryopolymers on the type of equipment required, as well as steps to reduce the amount of liquid nitrogen used in the process. They also guided the company to use more efficient ways to control system hardware. It is estimated that more than 300 million tires nationwide are produced per year. Cryopolymers expects to reach a production rate of 5,000 tires recycled per day.

Source record↗
NASA NTRS1996

Comparison of aerobically-treated and untreated crop residue as a source of recycled nutrients in a recirculating hydroponic system

This study compared the growth of potato plants on nutrients recycled from inedible potato biomass. Plants were grown for 105 days in recirculating, thin-film hydroponic systems containing four separate nutrient solution treatments: (1) modified half-strength Hoagland's (control), 2) liquid effluent from a bioreactor containing inedible potato biomass, 3) filtered (0.2 micrometer) effluent, and 4) the water soluble fraction of inedible potato biomass (leachate). Approximately 50% of the total nutrient requirement in treatments 2-4 were provided (recycled) from the potato biomass. Leachate had an inhibitory effect on leaf conductance, photosynthetic rate, and growth (50% reduction in plant height and 60% reduction in tuber yield). Plants grown on bioreactor effluent (filtered or unfiltered) were similar to the control plants. These results indicated that rapidly degraded, water soluble organic material contained in the inedible biomass, i.e., material in leachate, brought about phytotoxicity in the hydroponic culture of potato. Recalcitrant, water soluble organic material accumulated in all nutrient recycling treatments (650% increase after 105 days), but no increase in rhizosphere microbial numbers was observed.

NASA Discipline Life Support Systems↗
NASA NTRS1982

Process for the production of ultrahigh purity silane with recycle from separation columns

Tri- and dichlorosilanes formed by hydrogenation in the course of the reaction of metallurgical silicon, hydrogen and recycle silicon tetrachloride are employed as feed into a separation column arrangement of sequential separation columns and redistribution reactors which processes the feed into ultrahigh purity silane and recycle silicon tetrachloride. A slip stream is removed from the bottom of two sequential columns and added to the recycle silicon tetrachloride process stream causing impurities in the slip streams to be subjected to reactions in the hydrogenation step whereby waste materials can be formed and readily separated.

Coleman, Larry M.↗
NASA NTRS2013

Model-Based Diagnosis and Prognosis of a Water Recycling System

A water recycling system (WRS) deployed at NASA Ames Research Center s Sustainability Base (an energy efficient office building that integrates some novel technologies developed for space applications) will serve as a testbed for long duration testing of next generation spacecraft water recycling systems for future human spaceflight missions. This system cleans graywater (waste water collected from sinks and showers) and recycles it into clean water. Like all engineered systems, the WRS is prone to standard degradation due to regular use, as well as other faults. Diagnostic and prognostic applications will be deployed on the WRS to ensure its safe, efficient, and correct operation. The diagnostic and prognostic results can be used to enable condition-based maintenance to avoid unplanned outages, and perhaps extend the useful life of the WRS. Diagnosis involves detecting when a fault occurs, isolating the root cause of the fault, and identifying the extent of damage. Prognosis involves predicting when the system will reach its end of life irrespective of whether an abnormal condition is present or not. In this paper, first, we develop a physics model of both nominal and faulty system behavior of the WRS. Then, we apply an integrated model-based diagnosis and prognosis framework to the simulation model of the WRS for several different fault scenarios to detect, isolate, and identify faults, and predict the end of life in each fault scenario, and present the experimental results.

Roychoudhury, Indranil↗