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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 973 records · Page 54
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Development of Engineered Metal-Organic Framework (MOF) materials for perfluorooctane sulfonate (PFOS) Remediation

In this project, an engineered form of a Metal-Organic Framework (MOF) based material is developed for the removal of perfluorooctane sulfonate (PFOS) for real-world applications. The powdered MOF material has been demonstrated at the Pacific Northwest National Laboratory (PNNL) to selectively capture PFOS from distilled (DI) water with a large performance advantage over granulated activated carbon (GAC). In this project, the powdered material was transformed into an engineered form (using a polymer) to demonstrate PFOS adsorption capacity in tap water. PNNL developed and processed the MOF material in the engineering form (granules). After thorough characterization and stability testing, these engineered MOF granules were provided to an industrial collaborator, AVANTech, LLC, for testing and demonstration of continuous, long-term PFOS removal from tap water. The preliminary results showed PFOS sorption capacities at parts per billion (ppb) concentrations in tap water under a flow system. Also provided insight into sorbent-based material utilization in a continuous flow system. Further studies are required to optimize and understand sorption in such industrial-scale applications.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Engineered Pseudomonas putida simultaneously catabolizes five major components of corn stover lignocellulose: Glucose, xylose, arabinose, p-coumaric acid, and acetic acid

Valorization of all major lignocellulose components, including lignin, cellulose, and hemicellulose is critical for an economically viable bioeconomy. In most biochemical conversion approaches, the standard process separately upgrades sugar hydrolysates and lignin. Here, we present a new process concept based on an engineered microbe that could enable simultaneous upgrading of all lignocellulose streams, which has the ultimate potential to reduce capital cost and enable new metabolic engineering strategies. Specifically, we engineered Pseudomonas putida, a robust microorganism capable of catabolizing aromatic compounds, organic acids, and D-glucose, to utilize D-xylose and L-arabinose by tuning D-xylose transport and pentose phosphate pathway flux. Distinct L-arabinose pathways enabled D-glucose, D-xylose, and L-arabinose co-utilization in minimal medium using model compounds as well as corn stover hydrolysate. After modifying catabolite repression, our engineered P. putida simultaneously co-utilized five representative compounds from cellulose, hemicellulose, and lignin, demonstrating the feasibility of simultaneously upgrading total lignocellulosic biomass to value-added chemicals.

Elmore, Joshua R.↗
DOE OSTI2018

Bench‐Scale Evaluation of Hydrothermal Processing Technology for Conversion of Wastewater Solids to Fuels: Marrone et al.

ABSTRACT: Hydrothermal Liquefaction (HTL) and Catalytic Hydrothermal Gasification (CHG) proof‐of‐concept bench‐scale tests were performed to assess the potential of hydrothermal treatment for handling municipal wastewater sludge. HTL tests were conducted at 300 to 350 °C and 20 MPa on three different feeds: primary sludge, secondary sludge, and digested solids. Corresponding CHG tests were conducted at 350 °C and 20 MPa on the HTL aqueous phase output using a ruthenium‐based catalyst. Biocrude yields ranged from 25 to 37%. Biocrude composition and quality were comparable to biocrudes generated from algae feeds. Subsequent hydrotreating of biocrude resulted in a product with comparable physical and chemical properties to crude oil. CHG product gas methane yields on a carbon basis ranged from 47 to 64%. Siloxane concentrations in the CHG product gas were below engine limits. The HTL‐CHG process resulted in a chemical oxygen demand (COD) reduction of > 99.9% and a reduction in residual solids for disposal of 94 to 99%.

Marrone, P. A.↗
DOE OSTI2023

Sustainable production of plastic degrading enzymes

The 21st century faces the challenge of transitioning to a climate-neutral economy. This hurdle will need to be addressed in a myriad of approaches, including all societal spheres, as highlighted in several UN and EU reports, including new and accessed technologies. Among them, biotechnology can play a core role by exploiting its environmental benefits (e.g., substituting fossil-based products and expected greenhouse emission reductions). In some cases, biotech can even outperform fossil counterparts' features (e.g., the biodegradability of some bioplastics). Microalga is an attractive bioplastic feedstock in this scenario since it directly substitutes petroleum and captures CO2. However, albeit its environmental benefits, the microalgal process still needs to be tipped economically and the net-positive ecological impact improved to drive adoption. To that end, we envisioned the use of a green alga as a source of bioplastic feedstock and industrial enzymes, combining natural traits of microalgae with engineered properties in a resourceful process to petroleum-based products replacement. As proof of concept, we demonstrated that we could use C. reinhardtii, a green algae, to produce plastic-degrading enzymes. We assemble a vector to secrete PHL7, a recently described PETase, capable of degrading post-consumer PET plastic. We successfully engineered the cell line to secrete the plastic-degrading enzyme. We confirmed the secretion of the enzyme by observing halos in agar plates supplemented with plastic dispersions, enzymatic assays, zymograms, and protein sequencing of supernatant samples. This approach allows using green algae to replace petrochemical-derived plastic while producing the tool necessary to recycle existing plastics sustainably.

Dutra Molino, Joao Vitor↗
DOE OSTI2018

Molten Salt Reactor Salt Processing – Technology Status

This report presents a summary of 752 citations related to molten salt reactor development at Oak Ridge National Laboratory (ORNL). This effort was initiated with a focused purpose of locating technical information related to the chemical processing of fluoride salts to support the Th-232/U-233 fuel-cycle molten-salt breeder reactor. However, it soon became apparent that technical information on chemical processing was spread throughout numerous reports spanning decades of time. Therefore, the search effort was broadened to include any information deemed relevant to MSR development at ORNL. In addition, this report provides an overview of the engineering requirements of a chemical processing plant to support the Th-232/U-233 fuel-cycle molten salt breeder reactor (MSBR). This includes descriptions of the unit operations and flowsheets development at ORNL. The transition from the two-fluid MSBR to the single-fluid MSBR was largely due to the development of new separations technologies for the management of uranium, protactinium, and fission products in fluoride molten salts. The development and refinement of chemical processing plant flowsheets continued throughout the entirety of the MSBR program at ORNL. A great deal of experimental and theoretical work was performed in support of the unit operations and flowsheets described here.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2023

Virtual Engineering of Low-Temperature Conversion

In this work, we present the development of an overarching software framework and supporting multiphysics models to simulate the end-to-end process of biomass conversion. This virtual engineering (VE) software is designed with the goal of accelerating research and development and reducing risk for market-relevant biomass conversion processes. We currently support multiple models, computing paradigms, and fidelities representing the steps of feedstock pretreatment, enzymatic hydrolysis, and bioconversion. Although this VE approach was developed to support a biomass workflow, we have designed each component in a way that allows us to easily support new domains, unit models, and feedstocks. We begin by presenting the user-facing aspects of the VE software and highlight how simulated elements are defined and linked by VE functions. We then present an overview of the high-fidelity computational fluid dynamics (CFD) models developed to support our target domain before segueing into our efforts to develop accurate and fast surrogate models, capturing the salient outcomes from the CFD simulations in a significantly less computationally demanding manner. We then present how VE calculations interface with a commercial techno-economic analysis software, Aspen Plus. We conclude by presenting VE case studies that leverage these methods and discuss how our methods can be extended to support a wide variety of accelerated biofuel commercialization pathways in the future.

biofuel↗
DOE OSTI2015

Electricity storage using a thermal storage scheme

The increasing use of renewable energy technologies for electricity generation, many of which have an unpredictably intermittent nature, will inevitably lead to a greater demand for large-scale electricity storage schemes. For example, the expanding fraction of electricity produced by wind turbines will require either backup or storage capacity to cover extended periods of wind lull. This paper describes a recently proposed storage scheme, referred to here as Pumped Thermal Storage (PTS), and which is based on “sensible heat” storage in large thermal reservoirs. During the charging phase, the system effectively operates as a high temperature-ratio heat pump, extracting heat from a cold reservoir and delivering heat to a hot one. In the discharge phase the processes are reversed and it operates as a heat engine. The round-trip efficiency is limited only by process irreversibilities (as opposed to Second Law limitations on the coefficient of performance and the thermal efficiency of the heat pump and heat engine respectively). PTS is currently being developed in both France and England. In both cases, the schemes operate on the Joule-Brayton (gas turbine) cycle, using argon as the working fluid. However, the French scheme proposes the use of turbomachinery for compression and expansion, whereas for that being developed in England reciprocating devices are proposed. The current paper focuses on the impact of the various process irreversibilities on the thermodynamic round-trip efficiency of the scheme. Consideration is given to compression and expansion losses and pressure losses (in pipe-work, valves and thermal reservoirs); heat transfer related irreversibility in the thermal reservoirs is discussed but not included in the analysis. Results are presented demonstrating how the various loss parameters and operating conditions influence the overall performance.

42 ENGINEERING↗
DOE OSTI2025

Evaluating Chemical Kinetics Predictions for Propane Using 3-D and 0-D Models in a Boosted Spark-Ignited Engine

Propane has been shown to be a promising alternative fuel to reduce emissions while simultaneously achieving high efficiencies in medium- and heavy-duty engines. These high-power density applications require boosted engines which, combined with high compression ratio, can lead to auto-ignition and knock. While three-dimensional (3-D) computational fluid dynamics (CFD) models are often used for resolving the complex fluid flow in engines, these models can become computationally expensive when simulating detailed chemical kinetics. Likewise, zero-dimensional (0-D) models are computationally concise enough for kinetics development, but lack any flow-field information which governs the flame propagation processes in spark ignition (SI) engines. This work presents a comprehensive comparison between 3-D and 0-D closed cycle simulations at knocking conditions in a high compression ratio high stroke-to-bore ratio propane engine. In order to initialize the flow-field for the 3-D closed cycle (intake valve closing, (IVC) to exhaust valve opening, (EVO)) simulation, a motored multi-cycle 3-D model was run using Converge to create a map at IVC, reducing the computational time. The map allowed a non-homogeneous 3-D closed cycle simulation to be satisfactorily validated against experiments, while a homogeneous case using only the turbulence field mapping was also simulated, mimicking 0-D modeling. The 3-D simulations were used to prescribe the initial conditions (e.g., IVC thermodynamics, speciation, burn-rate profile) for a 2-zone 0-D SI engine model in Chemkin Pro for both cases. It was found that 2-zone 0-D modeling underpredicted the knock onset timing, likely due to the lack of thermal stratification in the unburned gas region. Future work will carry multi-zone 0-D modeling to capture the fuel auto-ignition in the unburned region.

Douvry-Rabjeau, Julien [Oakland University, Roches↗
DOE OSTI2022

Understanding slurry formulations to guide solution-processing of solid electrolytes

Scalable processing of thin solid electrolytes is crucial for engineering solid-state batteries with practical energy densities. To leverage existing battery production infrastructure, pathways for solution processing of solid electrolyte films must be investigated. Here, roll-to-roll compatible film preparation of aluminum-doped lithium lanthanum zirconate oxide was studied. Four slurry configurations accounting for different solvent properties and solid loadings were evaluated to investigate the ternary interactions within the dispersions. Rheological and coating stability analyses were carried out on the processed slurries. The analysis and characterization indicated that improved component interactions within the ethanol/toluene system result in homogenized distribution of the particles, binder, and plasticizer, and enable the extraction of free-standing thin films with thicknesses of 20 μm and large area (>15 in. 2 ). The drawbacks and opportunities of several protocols for high temperature sintering of the dried green films were investigated. This study highlights the importance of engineering dispersions during the development of processing protocols for solid electrolytes and provides guidelines for the best practices that can be leveraged for solution processing–based fabrications for a wide range of solid electrolyte materials.

25 ENERGY STORAGE↗
DOE OSTI2024

Improving Additive Manufactured Component Performance through Multi-Scale Microstructure Simulation and Process Optimization

The purpose of this project was to utilize computational tools to understand the relationships between processing, microstructure, and properties for additively manufactured (AM) aluminum alloys for automotive applications, and to provide an engineering solution for helping to optimize process conditions. The project leverages ORNL developments in computational modeling, including AM process modeling, phase-field based microstructure evolution predictions, and data analytics techniques for mapping process conditions to material outcomes. The project utilized an Al-Cu-Mn-Zr alloy as a model material for studying formation of defects and microstructural features in response to variations in process conditions. Based on both pre-existing experimental data and simulation results, statistical process maps were constructed to identify regions of process space with minimal defect formation and advantageous microstructures and properties. The software tools used for this purpose were successful disseminated to GM, who were able to successful compile the relevant HPC codes within their own computing ecosystem and perform initial calculations to reproduce ORNL results.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Process model and capacity upgrades of the CTI-4000 liquid helium coldbox

Fermi National Accelerator Laboratory (FNAL) is in the process of re-commissioning a vintage CTI-4000 liquid helium coldbox, initially supplied by CTI-Cryogenics/Sulzer to Los Alamos in 1979. The coldbox was originally designed as a liquid helium refrigerator with capacity of ∼1200 W at nominal 4-K. The process utilized LN{sub 2} precooling, in-series operation of two centrifugal gas bearing turboexpanders and final Joule-Thomson (J-T) expansion. At FNAL, the coldbox will be utilized as a liquefier to support 2-K operations. A process model was developed to aid in the upgrade decisions and used to determine the nominal capacity of the liquefier. Capacity upgrades are achieved by safely utilizing the internal LN2 precooler, the addition of a 3-inch reciprocating wet expansion engine and increasing the overall process pressure by recertifying two limiting pressure vessels to a higher MAWP.

43 PARTICLE ACCELERATORS↗
DOE OSTI2022

Friction Stir Processed Repair Welding of Dry Storage Canisters and Mitigation Strategies: Effect of Engineered Barrier Layer on Environmental Degradation

The proposed project aims to develop a friction sir based repair technique to heal cracks of stainless steel dry storage canisters (DSCs), created by the effect of stress corrosion cracking (SCC). In real service conditions, the welded parts of the canisters become prone to SCC under exposure to aggressive chemical environment. The focus of the project is on developing a mitigation strategy that can be implemented for countering SCC in DSCs following a two-pronged approach: (i) apply friction stir processing (FSP) as a crack repair technique while creating compressive residual stresses at the canister material surface, thus improving resistance against SCC; (ii) add molybdenum and/or nitrogen by friction stir based alloying process to create compositions that improve pitting resistance and thus enhance resistance against SCC. The specific project objectives are listed below: • Investigate FSW of 304L SS a potential repair welding technique of dry storage canisters; • Optimize the FSW parameters to introduce surface compressive stress profiles in the weldments; • Develop a FSP method to surface alloy the 304L with nitrogen and Mo by adding CrN and Mo powders; • Evaluate the surface compressive residual stress profile during FSW and FSP processes; • Evaluate the localized corrosion resistance of the FSW and FSP samples as a function of temperature, chloride concentration, and surface alloy composition; • Evaluate the SCC behavior of the FSW and FSP samples as a function of stress, chloride concentration, and temperature at different surface chemistries and induced residual stress profiles.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2019

Autogenous healing of Engineered Cementitious Composites (ECC) based on MgO-fly ash binary system activated by carbonation curing

Developing self-healing of concrete cracks represents a critical approach for extending material longevity. If demonstrated on concretes with CO 2 stored through carbonation curing, self-healing can further mitigate infrastructure lifecycle emissions. In this study, the self-healing process is investigated on novel Engineered Cementitious Composites (ECC) based on binary blends of reactive MgO cement and siliceous fly ash activated by carbonation. The self-healing was observed under cyclic wetting and drying exposures and was characterized by measurements of resonance frequency, optical microscopy and X-ray computed microtomography (XCT). Thermogravimetric analysis, X-ray powder diffraction and scanning electron microscopy were employed to assist in identifying healing products and mechanisms. It was found that micro-cracks could be autogenously filled in 7 wet-dry cycles, as evidenced by over 95% recovery of resonance frequency and healed crack appearance under optical microscopic observation. Nevertheless, the composite mechanical performance, particularly tensile strength and ductility, did not fully recover with respect to the uncracked specimens. The inadequate post-healing mechanical properties were consistent with XCT observations that indicated low material densities in the cracked area. Based on the chemical and microstructural characterizations, it was determined that nesquehonite crystallites were responsible for the crack filling. Although the nesquehonite filled cracks will be less permeable to invasion of reactive fluids, novel strategies are needed to establish more robust healing capability to completely restore the crack bridging and composite tensile performance.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Functional remediation components: A conceptual method of evaluating the effects of remediation on risks to ecological receptors

Governmental agencies, regulators, health professionals, tribal leaders, and the public are faced with understanding and evaluating the effects of cleanup activities on species, populations, and ecosystems. While engineers and managers understand the processes involved in different remediation types such as capping, pump and treat, and natural attenuation, there is often a disconnect between (1) how ecologists view the influence of different types of remediation, (2) how the public perceives them, and (3) how engineers understand them. The overall goal of the present investigation was to define the components of remediation types (= functional remediation). Objectives were to (1) define and describe functional components of remediation, regardless of the remediation type, (2) provide examples of each functional remediation component, and (3) explore potential effects of functional remediation components in the post-cleanup phase that may involve continued monitoring and assessment. Functional remediation components include types, numbers, and intensity of people, trucks, heavy equipment, pipes, and drill holes, among others. Several components may be involved in each remediation type, and each results in ecological effects, ranging from trampling of plants, to spreading invasive species, to disturbing rare species, and to creating fragmented habitats. In some cases remediation may exert a greater effect on ecological receptors than leaving the limited contamination in place. A goal of this conceptualization is to break down functional components of remediation such that managers, regulators, and the public might assess the effects of timing, extent, and duration of different remediation options on ecological systems.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

SFAI and Related Technologies

Researchers at Los Alamos have developed Swept-Frequency Acoustic Interferometry (SFAI) a technology that enables businesses to have greater control over their industrial processes, allowing for significantly improved efficiency by giving operators vital composition and flow rate information in real-time. This technology fills the information gap by providing this data non-invasively and at a fraction of the cost of traditional composition meters. SFAI uses engineered ultrasound and advanced signal processing to characterize multiphase flow (e.g., liquids, gasses, multi-phase mixtures) and other flows inside sealed containers and flow pipes. By being both low-cost and non-invasive, this technology is set to disrupt the current oil field monitoring state-of-the-art by providing individual well-level composition data, compared to the multi-well macroscopic information that is currently available. We are seeking a commercialization partner to license the technology or fund us through a Cooperative Research and Development Agreement (CRADA) to a further develop a usable product for commercial purposes.

03 NATURAL GAS↗
DOE OSTI2019

Subsurface Seismic Structure Around the Sanford Underground Research Facility

To address the fundamental challenges of understanding processes associated with enhanced or engineered geothermal systems (EGS), teams from the EGS Collab SIGMA-V project are conducting stimulations at the Sanford Underground Research Facility. Various modalities of geophysical observations are collected and analyzed, and different types of parameters are modeled to help investigate these critical processes. Among these parameters, the three-dimensional stress field is one of the primary objectives. Seismic velocity models have been used to estimate the 3D stress field for other regions. A detailed seismic velocities and density model can help us infer spatial variations of the stress field in the study area. We inverted the 3D seismic structure around the site by using body-wave travel times, surface-wave dispersions and gravity observations simultaneously. The resulting model will be a starting point for more detailed investigations and could also be used to study subsurface geological and stress field variations of the broad area.

Chai, Chengping↗