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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 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Cost and life cycle analysis for deep CO 2 emissions reduction of steelmaking: Blast furnace-basic oxygen furnace and electric arc furnace technologies

Iron and steel manufacturing is the largest contributor to CO 2 emissions among heavy industries worldwide. This is mostly due to the use of coal in blast furnace-basic oxygen furnace (BF-BOF) process for virgin (primary) steel production. The electricity generation mix used in the electric arc furnace (EAF) process to recycle scrap steel also contributes to the CO 2 emission associated with secondary steel production. To decarbonize iron and steel sector, we investigated decarbonization options for BF-BOF and EAF processes, including energy efficiency, carbon capture and storage, and the use of clean energy sources, in various BF-BOF and EAF process configurations. Additionally, for each decarbonization approach, we evaluated the CO 2 reduction potential via life cycle analysis (LCA) and estimated the associated cost through techno-economic analysis (TEA). A typical U.S. BF-BOF for virgin steel production has a cradle-to-gate (CTG) CO 2 emissions of 1,990 kg/MT steel with a levelized cost of steel (LCOS) of $\$439$/MT steel, while a typical U.S. EAF process for secondary steel production in the United States has a CTG CO 2 emissions of 270 kg/MT steel with a LCOS of $\$365$/MT steel. Combining renewable energy sources and carbon capture, BF-BOF CTG CO 2 emissions can be reduced to 16 kg/MT steel, and EAF configurations can achieve similar deep reductions to reach 25 kg/MT steel. The corresponding LCOS with these decarbonization levels is estimated to increase to $\$542$/MT steel and $\$348$/MT steel, respectively. The estimated CO 2 avoidance costs vary from -$\$90$/MT CO 2 to $\$646$/MT CO 2 , depending on the various decarbonization technologies and energy prices.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2018

Modeling error PDF optimization based wavelet neural network modeling of dynamic system and its application in blast furnace ironmaking

In general, the modeling errors of dynamic system model are a set of random variables. The traditional performance index of modeling such as means square error (MSE) and root means square error (RMSE) can not fully express the connotation of modeling errors with stochastic characteristics both in the dimension of time domain and space domain. Therefore, the probability density function (PDF) is introduced to completely describe the modeling errors in both time scales and space scales. Based on it, a novel wavelet neural network (WNN) modeling method is proposed by minimizing the two-dimensional (2D) PDF shaping of modeling errors. First, the modeling error PDF by the tradional WNN is estimated using data-driven kernel density estimation (KDE) technique. Then, the quadratic sum of 2D deviation between the modeling error PDF and the target PDF is utilized as performance index to optimize the WNN model parameters by gradient descent method. Since the WNN has strong nonlinear approximation and adaptive capability, and all the parameters are well optimized by the proposed method, the developed WNN model can make the modeling error PDF track the target PDF, eventually. Simulation example and application in a blast furnace ironmaking process show that the proposed method has a higher modeling precision and better generalization ability compared with the conventional WNN modeling based on MSE criteria. Furthermore, the proposed method has more desirable estimation for modeling error PDF that approximates to a Gaussian distribution whose shape is high and narrow.

Modelling↗
DOE OSTI2018

Data-Driven Robust M-LS-SVR-Based NARX Modeling for Estimation and Control of Molten Iron Quality Indices in Blast Furnace Ironmaking

Optimal operation of an industrial blast furnace (BF) ironmaking process largely depends on a reliable measurement of molten iron quality (MIQ), which is not feasible using the conventional sensors. This paper proposes a novel data-driven robust modeling method for online estimation and control of MIQ indices. First, to completely capture the nonlinear dynamics of the BF process, the nonlinear autoregressive exogenous (NARX) model is constructed for the MIQ indices. Then, considering that the standard least-squares support vector regression (LS-SVR) cannot directly cope with the multi-output problem, the multi- task transfer learning is proposed to design a novel multi-output LS-SVR (M-LS-SVR) for learning of the NARX model. Furthermore, a novel M-estimator is proposed to reduce the interference of outliers and improve the robustness of the M-LS- SVR model. Since the weights of different outlier data are properly given by the weight function, their corresponding contributions on modeling can be properly distinguished, thus a robust modeling result can be achieved. Finally, a novel multi- objective evaluation index on modeling performance is developed by comprehensively considering the root mean square error of modeling and the correlation coefficient on trend fitting, based on which the NSGA-II algorithm is used to globally optimize the model parameters. Both experiments using industrial data and industrial applications illustrate that the proposed method can eliminate the adverse effect caused by the fluctuation of data in BF process efficiently, which indicates its stronger robustness and higher accuracy. Moreover, control testing shows that the developed model can be well applied to realize data-driven control of the BF process.

blast cavities, Control↗
DOE OSTI2024

The RAPTR furnace: a rapid heating and cooling sample furnace for in situ X-ray scattering studies of temperature-induced reactions

In situX-ray scattering provides valuable insights into the mechanisms and kinetics of reactions and structural transformations. For reactions and structural transformations primarily driven by temperature, and not coupled to chemical/electrochemical triggers, our ability to initiate and quench processes thermally is a practical limit for probing fast reactive phenomena. Meaningful quantitative analysis requires the dynamic phenomena to be triggered on fast time scales relative to the reaction/transformation kinetics. This article describes a new sample furnace, the Rapid-Actuating Pneumatic Thermal Reactor or RAPTR, for time-resolvedin situX-ray scattering studies initiated by temperature. The RAPTR quickly heats and cools samples by translating them into and out of a pre-heated hot zone. Using diffraction thermometry, it is shown that the samples can be heated/cooled in 10 s or less, with temperatures up to ∼1000°C being accessible. The application of the RAPTR furnace is demonstrated by exploring a fast solid-state reaction: the synthesis of scheelite-type lead tungstate, PbWO 4 , from PbO and WO 3 for which Pb 3 WO 6 is identified as a previously unrecognized reaction intermediate.

Chemistry↗
DOE OSTI2026

ResStock Measure Documentation: Propane Furnace 95% AFUE and Fuel Oil Furnace 88% AFUE

This report is part of a series describing different ResStock (TM) measures. "Measures" refers to energy efficiency retrofits that can be applied to buildings during modeling. This documentation covers the "Propane Fuel 95% AFUE and Fuel Oil Furnace 88% AFUE" measure upgrade methodology and briefly discusses key results.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2021

Iron speciation in blast furnace slag cements

Slag-containing pastes and concretes were analysed by element-specific synchrotron-based techniques to determine the speciation of iron on crushed materials through spatially resolved micro-spectroscopic studies. The investigated cement samples were hydrated either in the laboratory, or exposed to river or sea water. Metallic iron, along with minor proportions of iron sulphide and magnetite was detected in the laboratory sample. Iron sulphide, goethite, and siliceous hydrogarnet were discovered in the blended slag cements hydrated in contact with river water for up to 7 years. In contrast, no Fe(0) was observed in blended concretes exposed to sea water. Instead, iron sulphide, iron(II)-hydroxide and -oxide, hematite, magnetite, siliceous hydrogarnet, and goethite were detected as well as ilmenite (FeTiO{sub 3}) in the aggregates. The strong acceleration of Fe oxidation in samples exposed to sea water and the long-term passivation observed in the other samples indicate comparable processes as those occurring on steel bars.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Glass production rate in electric furnaces for radioactive waste vitrification

Correlating the melting rates of feeds in electric melters with results of simple laboratory experiments can help evaluate melter feed additives and their effects on melting rate, and support the feed scheduling and plant operation. A recently proposed melting rate correlation (MRC) equation, relating the melting rate to melt viscosity, feed-to-glass conversion heat, and cold-cap bottom temperature, was tested using data from experiments covering various feed compositions and melter operating parameters. The MRC equation is shown to reasonably represent the measured data and thus can be used to quantify how individual variables (melt viscosity, cold-cap bottom temperature, conversion heat, melter operating temperature, and bubbling rate) affect the glass production rate.

Lee, Seung Min↗
DOE OSTI2020

A Numerical Study on the Energy Performance of a Novel Furnace With Acidic Gas Trap Absorbers

Natural gas furnaces are widely used in US residential and commercial building markets. An important issue for natural gas furnaces is serious corrosion and fouling problems caused by acidic gas, such as SOx. An advanced adsorption technology based on acidic gas trap (AGT) absorbers offers the possibility to remove SOx acidic gas from natural gas furnaces with high efficiency and low cost, thereby enabling the development of condensing furnaces without the use of expensive corrosion resistant materials in the heat exchanger. A three-dimensional (3D) computational fluid dynamics (CFD) model has been developed to evaluate the heat transfer performance of a furnace with AGT absorbers and to compare it with a baseline conventional furnace without the AGT. Moreover, an axisymmetric model has been built focusing on the absorbing process in the AGT. The baseline conventional furnace used for the study is a commercial condensing furnace (Rheem 92% AFUE 84,000 BTU Multi-Position Gas Furnace). This furnace was completely disassembled, and the dimensions of each part were carefully measured and used to build a detailed CFD model. A model representing the new furnace, incorporating the AGT absorbers, was developed by adding the AGT system to the conventional furnace model. For the CFD analysis, a mixture model was employed to characterize the heat and mass transfer during the condensing process in the furnace while considering three components—air, water vapor and liquid water. Condensation takes place in the condensing heat exchanger, where water vapor changes phase to liquid water, and the latent heat is thus used in the furnace for useful heating. The simulation results characterize the energy performance of both the conventional furnace and the novel furnace with AGT absorbers, as well as the reactive processing in the AGT. These results provide insightful guidance for the development of the AGT absorber-based furnace from the perspective of its energy performance and will be used to further optimize this novel furnace design.

Laclair, Tim↗
NASA NTRS1997

High Temperature Transparent Furnace Development

This report describes the use of novel techniques for heat containment that could be used to build a high temperature transparent furnace. The primary objective of the work was to experimentally demonstrate transparent furnace operation at 1200 C. Secondary objectives were to understand furnace operation and furnace component specification to enable the design and construction of a low power prototype furnace for delivery to NASA in a follow-up project. The basic approach of the research was to couple high temperature component design with simple concept demonstration experiments that modify a commercially available transparent furnace rated at lower temperature. A detailed energy balance of the operating transparent furnace was performed, calculating heat losses through the furnace components as a result of conduction, radiation, and convection. The transparent furnace shells and furnace components were redesigned to permit furnace operation at at least 1200 C. Techniques were developed that are expected to lead to significantly improved heat containment compared with current transparent furnaces. The design of a thermal profile in a multizone high temperature transparent furnace design was also addressed. Experiments were performed to verify the energy balance analysis, to demonstrate some of the major furnace improvement techniques developed, and to demonstrate the overall feasibility of a high temperature transparent furnace. The important objective of the research was achieved: to demonstrate the feasibility of operating a transparent furnace at 1200 C.

Bates, Stephen C.↗
DOE OSTI2022

Clean Condensing Gas Furnace

Natural gas furnaces are the most common space heating equipment in the U.S. residential and commercial building markets. However, current residential natural gas condensing furnaces generate substantial acidic condensate as well as significant emissions of sulfur oxides (SOx), nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbons (HC), and methane (CH 4 ) contributing to environmental degradation of air, water, and soil. This report describes a novel solution to reduce the environmental impact of natural gas condensing furnaces based on the technology of a monolithic acidic gas reduction (AGR) catalyst for SOx trapping, NOx redox to nitrogen, and oxidation of formic acid, CO, HC, and CH 4 . The AGR technology offers the following benefits: (1) a neutral furnace condensate with a pH of ~7, allowing its safe release into the sewer system thus eliminating a second drainage system; (2) trapping and removing nearly all SOx emissions; (3) NOx emissions nearly at nearly 1-2 ng/J, more than 95% lower than new emissions standards in California; (4) the use of a low-cost heat exchanger as a condensing heat exchanger (HX) since the condensate is not acidic, avoiding the need for expensive stainless steel alloys; and (5) unburnt fuel energy recovery to boost efficiency.The AGR component and AGR-enabled furnace performance were broadly tested to determine their effects on long-term reliability and durability, as well as SOx storage and regeneration activity. The AGR regeneration does not impair the performance in achieving neutral condensate and ultra-low NOx emissions, and the AGR catalyst subjected to regeneration activities continued to function well and achieved slightly better annual fuel utilization efficiency (AFUE). The 400-hour reliability and durability test of the retrofitted condensing furnace with the AGR component shows that the furnace unit still achieves a neutral furnace condensate with a pH of ~7 and enables 0~3 ng/J of NOx emissions. However, the 400-hour operation slightly degraded the AFUE because of soot particle accumulation caused by frequent incomplete combustion owing to inappropriate condensate drainage during testing. Thus, proper condensate drainage is critical for AGR-enabled furnaces. Furthermore, neutron computed tomography was employed to survey the aged AGR component and demonstrate high-resolution 2D and 3D representations for the nondestructive diagnosis of the AGR component. The tomography showed that the AGR component did not deform or suffer broken AGR channels. A new AGR catalyst with low precious metal loading was preliminarily explored to identify a pathway of optimizing AGR material loading and maximizing acidic gas reduction at low cost. The new AGR component can reduce precious metal loading by 38% and still achieve neutral condensate and ultralow NOx emissions. The furnace with the AGR component of low Pt/Rh loading enables a maximum AFUE of 97%, which is meaningfully higher than the original furnace. Long-duration testing for the furnace enabled with the low precious metal loading AGR component will be vital in future research. Although the current work demonstrates a proof of concept for the AGR-enabled furnace, the AGR assembly needs to be optimized and integrated into the design of new OEM furnace products. Furthermore, the AGR technology can be applied not only for residential gas furnaces, but also for commercial rooftop units, gas heat pumps, gas-fired water heaters, combustion boilers, and other systems.

03 NATURAL GAS↗
DOE OSTI2021

Experimental Investigation of a Novel Membrane-Based Condensing Heat Exchanger for High Efficiency Furnaces

Building space heating consumes approximately one-third of all global natural gas end use. Higher-efficiency (i.e., condensing) furnaces constitute only about 30% of the annual furnace shipments in the United States because the condensing heat exchangers must use highly expensive, corrosion-resistant materials to be protected from acidic components in the furnace flue gas stream. Increasing the market share of high-efficiency furnaces will reduce greenhouse gas emissions. This study developed and tested a benchtop prototype of a novel membrane-based heat exchanger (MHX) for high-efficiency furnaces to achieve nonacidic condensation via nanoporous membranes. Test results show that both sensible and latent heat were recovered by the MHX, and the fraction of latent heat recovery ranged from about 25% to 45% over the range of operating conditions evaluated. The amount of water condensed through the MHX increased with the increase of flue gas flow rate and decreased with increasing coolant temperature. The fraction of latent heat recovery decreased with the increase of flue gas flow rate and coolant temperature. The pH value of condensed water from the MHX was only mildly acidic, varying from 5.3 to 5.6 without any additional treatment, about 2.0 to 2.3 pH points higher (i.e., less acidic) than typical values for the condensate from conventional condensing furnaces. Therefore, feasibility of the MHX was experimentally verified, and the MHX could enable wider market penetration of highly energy-efficient condensing furnaces by reducing costs associated with managing the acid condensation compared with conventional condensing furnaces, possibly enabling the use of existing vent systems when replacing noncondensing furnaces (due to higher flue gas exit temperatures), and possibly reducing furnace first costs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗