Abstract. Understanding and extracting systems information is a time consuming, demanding and expensive process. Complicating factors are cross-boundary communication methods and tools. We combine an informal and formal systems engineering method; Lean manufacturing principles and Model Based systems Engineering (MBSE) resulting in Dynamic A3 architecture. Dynamic A3 Architecture is a hierarchy of overviews from super-system to sub-system that the reader can navigate through active links. We applied the method to a lube oil system of a gas turbine package. We found that Dynamic A3 Architecture can ease internal and cross boundary communication, train new employees, facilitate knowledge capture, and share common understanding of the "system of interest". A functional sequence diagram, which is a hybrid of a state and functional diagram, can assist in early validation of process applications.
A fiber-based Raman spectroscopy system was commissioned in an inert atmosphere for in situ analysis of high temperature molten salts. Speciation of samarium chloride was studied in the LiCl-KCl eutectic system at 500 °C. Raman spectra indicated trivalent samarium forms an octahedral SmCl63- complex with two detectable vibration modes. Chemical reduction experiments were conducted to investigate the coordination of divalent samarium in the same eutectic salt. The resulting spectra are reported and discussed in terms of complex formation and behavior of divalent samarium ions. Trivalent samarium was electrochemically reduced in situ and Raman spectra obtained were compared with those resulting from chemical reduction experiments. The spectra suggest divalent samarium ions form in LiCl-KCl only temporarily and spontaneously disproportionate into a mixture of trivalent samarium ions and metallic samarium.
Molten salt systems are under consideration for both energy generation and used fuel processing as part of the nuclear fuel cycle. Generation IV nuclear reactor designs use molten salts as both coolants and fuel media. Advanced reprocessing technologies, such as the pyrochemical reprocessing of used nuclear fuel, rely on molten chloride melts as the electrolyte during electrochemical processing of used nuclear fuel. Before any of these technologies can reach the industrial scale, techniques for the monitoring of nuclear material in a nondestructive and in situ manner must be further developed for molten salt systems. Real-time monitoring of nuclear material allows for process optimization, along with addressing nuclear security concerns associated with the diversion of actinide materials. In this study, we explore the use of Raman spectroscopy, employed using a fiber-coupled system, as a method for the in situ analysis of molten salt. We present the development of an automated, in situ Raman system for analysis of electroactive species in molten LiCl-KCl. The Raman modes of lanthanide chlorides, serving as actinide surrogates, were investigated in LiCl-KCl eutectic at 500°C and compared with the available literature. This work was performed under the auspices of the US Department of Energy (DOE) under contracts DE-NE0008262, DE-NE0008236 and DE-NE0008572, and the US Nuclear Regulatory Commission (NRC) under contract NRC-HQ-13-G-38-0027. Dr. Kenny Osborne serves as the program manager for the DOE awards and Ms. Nancy Hebron-Isreal serves as the grants program officer for the NRC award.
In order to maximize uranium resources and minimize the need to store radioactive material in geologic repositories, it is necessary to reprocess used nuclear fuel (UNF) to recycle the fissile material and transuranic isotopes that remain. The pyroprocessing operation developed by Argonne National Laboratory as part of the integral fast reactor project was designed to accomplish this goal while minimizing the risk of proliferation (1). Inclusion of oxide based UNF from the current light water reactor fleet into the metallic fuel based fast reactor cycle will require electrolytic oxide reduction in a LiCl-Li2O electrolyte (2). As a side reaction during the electroreduction of U, Li is codeposited on the cathode surface and subsequently dissolves, forming a ternary LiCl-Li2O-Li electrolyte (3, 4). The presence of metallic Li in the electrolyte negates the possibility of using the reference electrodes typically used for molten salt electrochemistry. The Li-Bi couple has been used as a reference electrode previously but has not yet been well characterized (5, 6). This work investigates the stability of the Li-Bi reference couple in varying solution chemistries typical of those found during electrolytic reduction of UO2. Acknowledgements: This work was performed under the auspices of the Department of Energy (DOE) under contracts DE-NE0008262 and DE-NE0008236, and the US Nuclear Regulatory Commission (NRC) under contracts NRCHQ-11-G-38-0039, NRC-HQ-10-G-38-0027, NRC-HQ-13-G-38-0027. W.P. and A.M acknowledge the Fellowship Award from the USNRC. Dr. Kenny Osborne serves as the program manager for the DOE award and Ms. Nancy Hebron-Isreal serves as the grants program officer for the NRC awards. References: 1. J. J. Laidler, J. E. Battles, W. E. Miller, J. P. Ackerman, E. L. Carls, Development of Pyroprocessing Technology. Progress in Nuclear Energy 31, 131-140 (1997). 2. S. D. Herrmann, S. X. Li, M. F. Simpson, S. Phongikaroon, Electrolytic Reduction of Spent Nuclear Oxide Fuel as Part of an Integral Process to Separate and Recover Actinides from Fission Products. Separation Science and Technology 41, 1965-1983 (2006). 3. T. Takenaka, K. Shigeta, H. Masuhama, K. Kubota, Influence of Some Factors upon Electrodeposition of Liquid Li and Mg. ECS Transactions 49, 441-448 (2009). 4. A. S. Dworkin, H. R. Bronstein, M. A. Bredig, Miscibility of Metals with Salts. VI. Lithium-Lithium Halide Systems. The Journal of Physical Chemistry 66, 572-573 (1962). 5. M. Iizuka, Y. Sakamura, T. Inoue, Electrochemical reduction of (U-40Pu-5Np)O2 in molten LiCl electrolyte. Journal of Nuclear Materials 359, 102-113 (2006). 6. X. Ning et al., Self-healing Li-Bi liquid metal battery for grid-scale energy storage. Journal of Power Sciences 275, 370-376 (2015).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.