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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Upgrading of Raw Coal and Coal Waste for Coal-Derived Graphene Process

Conference presentation at 47th International Technical Conference on Clean Energy (Clearwater Clean Energy Conference), Clearwater, Florida, July 23–27, 2023. The University of North Dakota Energy & Environmental Research Center (EERC) conducted a laboratory-scale coal-derived graphene (CDG) project focused on developing a technological process for making graphite from four U.S. domestic coals and coal wastes. Coal and coal waste preprocessing methods were developed and applied to clean and upgrade the coal precursors prior to graphitization and subsequent conversion to graphene products. Carbonization and graphitization of these preprocessed coals and coal wastes has produced graphite, which was used to make graphene oxide (GO) and reduced graphene oxide (rGO). Graphene quantum dots (GQDs) were also made from the raw and upgraded coal precursors.

01 COAL, LIGNITE, AND PEAT↗
NASA NTRS1987

Desulfurizing Coal With an Alkali Treatment

Experimental coal-desulfurization process uses alkalies and steam in fluidized-bed reactor. With highly volatile, high-sulfur bituminous coal, process removed 98 percent of pyritic sulfur and 47 percent of organic sulfur. Used in coal liquefaction and in production of clean solid fuels and synthetic liquid fuels. Nitrogen or steam flows through bed of coal in reactor. Alkalies react with sulfur, removing it from coal. Nitrogen flow fluidizes bed while heating or cooling; steam is fluidizing medium during reaction.

Ravindram, M.↗
NASA NTRS1981

Parametric analysis of closed cycle magnetohydrodynamic (MHD) power plants

A parametric analysis of closed cycle MHD power plants was performed which studied the technical feasibility, associated capital cost, and cost of electricity for the direct combustion of coal or coal derived fuel. Three reference plants, differing primarily in the method of coal conversion utilized, were defined. Reference Plant 1 used direct coal fired combustion while Reference Plants 2 and 3 employed on site integrated gasifiers. Reference Plant 2 used a pressurized gasifier while Reference Plant 3 used a ""state of the art' atmospheric gasifier. Thirty plant configurations were considered by using parametric variations from the Reference Plants. Parametric variations include the type of coal (Montana Rosebud or Illinois No. 6), clean up systems (hot or cold gas clean up), on or two stage atmospheric or pressurized direct fired coal combustors, and six different gasifier systems. Plant sizes ranged from 100 to 1000 MWe. Overall plant performance was calculated using two methodologies. In one task, the channel performance was assumed and the MHD topping cycle efficiencies were based on the assumed values. A second task involved rigorous calculations of channel performance (enthalpy extraction, isentropic efficiency and generator output) that verified the original (task one) assumptions. Closed cycle MHD capital costs were estimated for the task one plants; task two cost estimates were made for the channel and magnet only.

Owens, W.↗
DOE OSTI2016

Performance of an Integrated Gasification Direct-Fired Supercritical CO2 Power Cycle

This presentation discusses development and performance results of a coal gasification system integrated with a direct-fired supercritical CO2 (sCO2) power cycle. In this plant, coal is first gasified and cleaned in order to avoid introducing sulfur and particulate matter into the sCO2 cycle, with the sCO2 cycle’s oxy-combustor burning the cleaned syngas with oxygen in a recycled sCO2 stream. The plant is inherently amenable to carbon capture and storage (CCS) processes, as it produces a high pressure exhaust stream that is largely comprised of CO2. The baseline direct sCO2 cycle performance is discussed and compared to IGCC and oxy-coal AUSC reference plants with CCS. The sensitivity of the sCO2 cycle’s performance to various operating parameters is also discussed, as well as the effect of various heat integration options on thermal efficiency, operability, and cost.

Shelton, Walter↗
NASA NTRS1985

Reducing Coal Dust With Water Jets

Jets also cool and clean cutting equipment. Modular pick-and-bucket miner suffers from disadvantage: Creates large quantities of potentially explosive coal dust. Dust clogs drive chain and other parts and must be removed by hand. Picks and bucket lips become overheated by friction and be resharpened or replaced frequently. Addition of oscillating and rotating water jets to pick-and-bucket machine keeps down dust, cools cutting edges, and flushes machine. Rotating jets wash dust away from drive chain. Oscillating jets cool cutting surfaces. Both types of jet wet airborne coal dust; it precipitates.

Gangal, M. D.↗
DOE OSTI2014

Computational Capabilities for Predictions of Interactions at the Grain Boundary of Refractory Alloys

New high performance refractory alloys are critically required for improving efficiency and decreasing CO 2 emissions of fossil energy systems. The development of these materials remains slow because it is driven by a trial-and-error experimental approach and lacks a rational design approach. Atomistic Molecular Dynamic (MD) design has the potential to accelerate this development through the prediction of mechanical properties and corrosion resistance of new materials. The success of MD simulations depends critically on the fidelity of interatomic potentials. This project, in collaboration with Penn State, has focused on developing and validating high quality quantum mechanics based reactive potentials, ReaxFF, for Ni-Fe-Al-Cr-O-S system. A larger number of accurate density functional theory (DFT) calculations were performed to generate data for parameterizing the ReaxFF potentials. These potentials were then used in molecular dynamics (MD) and molecular dynamics-Monte Carlo (MD-MC) for much larger system to study for which DFT calculation would be prohibitively expensive, and to understand a number of chemical phenomena Ni-Fe-Al-Cr-O-S based alloy systems . These include catalytic oxidation of butane on clean Cr 2 O 3 and pyrite/Cr 2 O 3 , interfacial reaction between Cr 2 O 3 (refractory material) and Al 2 O 3 (slag), cohesive strength of at the grain boundary of S-enriched Cr compared to bulk Cr and Ssegregation study in Al, Al 2 O 3 , Cr and Cr 2 O 3 with a grain structure. The developed quantum based ReaxFF potential are available from the authors upon request. During this project, a number of papers were published in peer-reviewed journals. In addition, several conference presentations were made.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2023

Correlating chemistry and mass transport in sustainable iron production

Steelmaking contributes 8% to the total CO 2 emissions globally, primarily due to coal-based iron ore reduction. Clean hydrogen-based ironmaking has variable performance because the dominant gas–solid reduction mechanism is set by the defects and pores inside the mm- to nm-sized oxide particles that change significantly as the reaction progresses. While these governing dynamics are essential to establish continuous flow of iron and its ores through reactors, the direct link between agglomeration and chemistry is still contested due to missing measurements. In this work, we directly measure the connection between chemistry and agglomeration in the smallest iron oxides relevant to magnetite ores. Using synthesized spherical 10-nm magnetite particles reacting in H 2 , we resolve the formation and consumption of wüstite (Fe 1-x O)—the step most commonly attributed to whiskering. Using X-ray diffraction, we resolve crystallographic anisotropy in the rate of the initial reaction. Complementary imaging demonstrated how the particles self-assemble, subsequently react, and grow into elongated “whisker” structures. Our insights into how morphologically uniform iron oxide particles react and agglomerate in H 2 reduction enable future size-dependent models to effectively describe the multiscale aspects of iron ore reduction.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Using Machine Learning Tools to Predict Compressor Stall

Clean energy has become an increasingly important consideration in today’s power systems. As the push for clean energy continues, many coal-fired power plants are being decommissioned in favor of renewable power sources such as wind and solar. However, the intermittent nature of renewables means that dynamic load following traditional power systems is crucial to grid stability. With high flexibility and fast response at a wide range of operating conditions, gas turbine systems are poised to become the main load following component in the power grid. Yet, rapid changes in load can lead to fluid flow instabilities in gas turbine power systems. These instabilities often lead to compressor surge and stall, which are some of the most critical problems facing the safe and efficient operation of compressors in turbomachinery today. Although the topic of compressor surge and stall has been extensively researched, no methods for early prediction have been proven effective. This study explores the utilization of machine learning tools to predict compressor stall. The long short-term memory (LSTM) model, a form of recurrent neural network (RNN), was trained using real compressor stall datasets from a 100 kW recuperated gas turbine power system designed for hybrid configuration. Two variations of the LSTM model, classification and regression, were tested to determine optimal performance. The regression scheme was determined to be the most accurate approach, and a tool for predicting compressor stall was developed using this configuration. Overall, results show that the tool is capable of predicting stalls 5–20 ms before they occur. With a high-speed controller capable of 5 ms time-steps, mitigating action could be taken to prevent compressor stall before it occurs.

42 ENGINEERING↗
DOE OSTI2016

Performance Baseline for Direct-Fired sCO2 Cycles

NETL has conducted an evaluation of the performance and emissions for a direct coal-fired supercritical CO2 (sCO2) power plant, which has recently received interest as a potentially lower-cost, fossil-fuelled power source with inherent amenability to carbon capture. This study describes a baseline coal-fired cycle configuration, where coal is first gasified and cleaned in order to avoid introducing sulfur and particulate matter into the sCO2 cycle, with the sCO2 cycle’s oxy-combustor operating on syngas. The baseline sCO2 plant design yields a net plant thermal efficiency of 37.7% (HHV), with 98.1% CO2 capture at 99.4% purity. This compares favorably to the reference IGCC plant, which has a 31.2% net HHV thermal efficiency, and 90.1% CO2 capture rate at 99.99% purity. The sensitivity of the sCO2 plant’s performance to its process variables is discussed, as well as their effect on plant operability and cost surrogate variables.

Shelton, Walter↗
DOE OSTI2016

Performance Baseline for Direct-Fired sCO2 Cycles

NETL has conducted an evaluation of the performance and emissions for a direct coal-fired supercritical CO2 (sCO2) power plant, which has recently received interest as a potentially lower-cost, fossil-fuelled power source with inherent amenability to carbon capture. This study describes a baseline coal-fired cycle configuration, where coal is first gasified and cleaned in order to avoid introducing sulfur and particulate matter into the sCO2 cycle, with the sCO2 cycle’s oxy-combustor operating on syngas. The baseline sCO2 plant design yields a net plant thermal efficiency of 37.7% (HHV), with 98.1% CO2 capture at 99.4% purity. This compares favorably to the reference IGCC plant, which has a 31.2% net HHV thermal efficiency, and 90.1% CO2 capture rate at 99.99% purity. The sensitivity of the sCO2 plant’s performance to its process variables is discussed, as well as their effect on plant operability and cost surrogate variables.

Weiland, Nathan↗
DOE OSTI2017

Electrochemical Membrane for Carbon Dioxide Capture and Power Generation

FuelCell Energy, Inc. (FCE), in collaboration with AECOM Corporation (formerly URS Corporation) and Pacific Northwest National Laboratory, has been developing a novel Combined Electric Power and Carbon-dioxide Separation (CEPACS) system. The CEPACS system is based on electrochemical membrane (ECM) technology derived from FCE’s carbonate fuel cell products featuring internal (methane steam) reforming and carrying the trade name of Direct FuelCell®. The unique chemistry of carbonate fuel cells offers an innovative approach for separation of CO 2 from existing fossil-fuel power plant exhaust streams (flue gases). The ECM-based CEPACS system has the potential to become a transformational CO 2 -separation technology by working as two devices in one: it separates the CO 2 from the exhaust of other plants such as an existing coal-fired plant and simultaneously produces clean electric power at high efficiency using a supplementary fuel. The development effort was carried out under the U.S. Department of Energy (DOE) cooperative agreement DE-FE0007634. The overall objective of this project was to successfully demonstrate the ability of FCE’s ECM-based CEPACS system technology to separate ≥90% of the CO 2 from a simulated Pulverized Coal (PC) power plant flue gas stream and to compress the captured CO2 to a state that can be easily transported for sequestration or beneficial use. In addition, a key objective was to show, through the technical and economic feasibility study and bench scale testing, that the ECM-based CEPACS system is an economical alternative for CO 2 capture in PC power plants, and that it meets DOE’s objective related to the incremental cost of electricity (COE) for post-combustion CO 2 capture (no more than 35% increase in COE). The project was performed in three budget periods (BP). The specific objective for BP1 was to complete the Preliminary Technical and Economic Feasibility Study. The T&EF study was based on the carbon capture system size suitable for a reference 550 MW PC power plant. The specific objectives for BP2 were to perform (flue gas) contaminant effect evaluation tests, small area membrane tests using clean simulated flue gas, design a flue gas pretreatment system for processing of the gas feed to ECM, update the Technical & Economic Feasibility Study (T&EFS) incorporating results of contaminant effect tests and small area membrane tests, and to prepare a test facility for bench scale testing. The specific objectives for BP3 were to perform bench scale testing (parametric and long-duration testing) of a 11.7 m 2 ECM-based CO 2 capture, purification and compression system, and update (as final) the Technical and Economic Feasibility Study. In addition, an Environmental Health and Safety evaluation (assessment) of the ECM technology was included. This final technical report presents the progress made under the project.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2015

Design and construction of coal/biomass to liquids (CBTL) process development unit (PDU) at the University of Kentucky Center for Applied Energy Research (CAER)

This report describes a first phase of a project to design, construct and commission an integrated coal/biomass-to-liquids facility at a capacity of 1 bbl. /day at the University of Kentucky Center for Applied Energy Research (UK-CAER) – specifically for construction of the building and upstream process units for feed handling, gasification, and gas cleaning, conditioning and compression. The deliverables from the operation of this pilot plant [when fully equipped with the downstream process units] will be firstly the liquid FT products and finished fuels which are of interest to UK-CAER’s academic, government and industrial research partners. The facility will produce research quantities of FT liquids and finished fuels for subsequent Fuel Quality Testing, Performance and Acceptability. Moreover, the facility is expected to be employed for a range of research and investigations related to: Feed Preparation, Characteristics and Quality; Coal and Biomass Gasification; Gas Clean-up/ Conditioning; Gas Conversion by FT Synthesis; Product Work-up and Refining; Systems Analysis and Integration; and Scale-up and Demonstration. Environmental Considerations - particularly how to manage and reduce carbon dioxide emissions from CBTL facilities and from use of the fuels - will be a primary research objectives. Such a facility has required significant lead time for environmental review, architectural/building construction, and EPC services. UK, with DOE support, has advanced the facility in several important ways. These include: a formal EA/FONSI, and permits and approvals; construction of a building; selection of a range of technologies and vendors; and completion of the upstream process units. The results of this project are the FEED and detailed engineering studies, the alternate configurations and the as-built plant - its equipment and capabilities for future research and demonstration and its adaptability for re-purposing to meet other needs. These are described in some detail in this report, along with lessons learned.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2019

Cost curve of large-scale deployment of CO2-enhanced water recovery technology in modern coal chemical industries in China

China has emerged as a world leader in the coal chemical industry, which requires large amount of water and results in considerable CO2 emissions. This situation has led to the challenge of the CO2-Water nexus for China and particularly for the sustainable development of its coal chemical industry. CO2-enhanced water recovery (CO2-EWR) technology can provide large-scale CO2 mitigation and additional water supply in an integrated manner, especially in arid areas. Meanwhile, CO2 streams from industrial separation processes in the coal chemical industries are amenable to separation and can dramatically simplify or even dispense with the capture process. This study presents the first systematic assessment of a cost curve for onshore CO2-EWR potential using CO2 streams from industrial separation processes by an evaluation framework encompassing CO2 emission inventory, site suitability evaluation, and source–sink matching with techno-economic models. Preliminary results focused on the full capacity of several coal chemical processes as of 2015 suggest that CO2-EWR technology can mitigate 269 million tons of CO2 from industrial separation processes at relatively low cost ranging from 12 to 30 USD/t CO2 in China. Furthermore, 404 million tons of underground water could be produced for further desalination and utilization. When additional capacity under development could become fully operational, the emissions of 878 million tons of CO2 could be mitigated and provide 1318 million tons of vital water resources. Therefore, CO2-EWR technology can be essential to clean and sustainable development of the coal chemical industry and may provide low-cost opportunities to accelerate the deployment of large-scale CCUS projects in China.

CO2-enhanced water recovery, Modern coal chemical ↗
DOE OSTI2018

Small-scale pilot plant for gasification of coal and coal/biomass blends and conversion of derived syngas to liquid fuels via Fischer-Tropsch synthesis

This report describes the second phase of a project to design, construct and commission an integrated coal/biomass-to-liquids facility at a capacity of 1 bbl. /day at the University of Kentucky Center for Applied Energy Research (UK-CAER) – specifically for construction, commissioning and operating of the downstream process units for water-gas-shift, Fischer-Tropsch synthesis and balance of plant [BOP]. The deliverables from the operation of this pilot plant is firstly the liquid F-T products and finished fuels which are of interest to UK-CAER’s academic, government and industrial research partners. Going forward the facility will produce research quantities of F-T liquids and finished fuels for subsequent Fuel Quality Testing, Performance and Acceptability. Moreover, the facility is expected to be employed for a range of research and investigations related to: Feed Preparation, Characteristics and Quality; Coal and Biomass Gasification; Gas Clean-up/ Conditioning; Gas Conversion by -F-T Synthesis; Product Work-up and Refining; Systems Analysis and Integration; and Scale-up and Demonstration. Environmental Considerations - particularly how to manage and reduce carbon dioxide emissions from CBTL facilities and from use of the fuels will be a primary research objective. The results of this second phase study include the FEED study and detailed engineering design of the downstream processing units and BOP, the selection of a range of technologies and technology vendors, the as-built plant - its equipment and capabilities, and the results of two trial production runs, one with coal only and one with a coal/biomass blend. These are described in detail in this report.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2014

Jointly Sponsored Research Program on Energy Related Research

Cooperative Agreements, DE-FC26-08NT43293, DOE-WRI Cooperative Research and Development Program for Fossil Energy-Related Resources began in June 2009. The goal of the Program was to develop, commercialize, and deploy technologies of value to the nation’s fossil and renewable energy industries. To ensure relevancy and early commercialization, the involvement of an industrial partner was encouraged. In that regard, the Program stipulated that a minimum of 20% cost share be achieved in a fiscal year. This allowed WRI to carry a diverse portfolio of technologies and projects at various development technology readiness levels. Depending upon the maturity of the research concept and technology, cost share for a given task ranged from none to as high as 67% (two-thirds). Over the course of the Program, a total of twenty six tasks were proposed for DOE approval. Over the period of performance of the Cooperative agreement, WRI has put in place projects utilizing a total of $\$$7,089,581 in USDOE funds. Against this funding, cosponsors have committed $\$$7,398,476 in private funds to produce a program valued at $\$$14,488,057. Tables 1 and 2 presented at the end of this section is a compilation of the funding for all the tasks conducted under the program. The goal of the Cooperative Research and Development Program for Fossil Energy-Related Resources was to through collaborative research with the industry, develop or assist in the development of innovative technology solutions that will: • Increase the production of United States energy resources – coal, natural gas, oil, and renewable energy resources; • Enhance the competitiveness of United States energy technologies in international markets and assist in technology transfer; • Reduce the nation's dependence on foreign energy supplies and strengthen both the United States and regional economies; and • Minimize environmental impacts of energy production and utilization. Success of the Program can be measured by several criteria. Using the deployment of the federal funding with industrial participation as a performance criterion, over the course of the program, the cosponsors contributed more dollars than the federal funds. As stated earlier, a little more than half of the funding for the Program was derived from industrial partners. The industrial partners also enthusiastically supported the research and development activities with cash contribution of $\$$4,710,372.67, nearly 65% of the required cost share. Work on all of the tasks proposed under the Cooperative Agreement has been completed. This report summarizes and highlights the results from the Program. Under the Cooperative Agreement Program, energy-related tasks emphasized petroleum processing, upgrading and characterization, coal and biomass beneficiation and upgrading, coal combustion systems development including oxy-combustion, emissions monitoring and abatement, coal gasification technologies including gas clean-up and conditioning, hydrogen and liquid fuels production, and the development of technologies for the utilization of renewable energy resources. Environmental-related activities emphasized cleaning contaminated soils using microbial fuel cells, development of processes and sorbents for emissions reduction and recovery of water from power plant flue gas, and biological carbon capture and reuse. Technology enhancement activities included resource characterization studies, development of improved methods, monitors and sensors. In general the goals of the tasks proposed were to enhance competitiveness of U.S. technology, increase production of domestic resources, and reduce environmental impacts associated with energy production and utilization. Technologies being brought to commercialization as a result of the funds provided by the Cooperative Agreement contribute to the overall goals of the USDOE and the nation. Each has broad applicability both within the United States and abroad, thereby helping to enhance the competitiveness of U.S. energy technologies in international markets and assisting in technology transfer. Under the Cooperative Agreement Program, WRI has furthered the development of two different coal upgrading technologies. River Basin Energy technology was scaled-up and demonstrated at a nominal 40 tpd size. Similarly, WRI’s patented mercury removal technology further developed into WRITE Coal technology which was then integrated into oxy-combustion and gasification systems for IGCC and fuels production. Integrated systems with WRITE Coal technology applied at the front end represent substantial environmental and efficiency gains. A variation of the RBE coal upgrading technology is being commercialized as a torrefaction technology for woody biomass. WRI worked with EPRI and NIST to develop and improve mercury calibration standards for emissions monitoring. Working with Chart Energy and Chemicals, WRI scaled-up compact reactor technology for the synthesis of fuels and chemicals from syngas. Compact reactor technology represents a five-fold increase in productivity over conventional reactors making smaller-scale distributed synthesis plants an economical viability. Similarly, WRI's patented mixed alcohol synthesis catalyst production is being scaled-up in collaboration with a commercial catalyst manufacturer.

99 GENERAL AND MISCELLANEOUS↗