2016-Sustainable Industrial Processing Summit
SIPS 2016 Volume 9: Molten Salts and Ionic Liquids, Energy Production

Editors:Kongoli F, Gaune-Escard M, Turna T, Mauntz M, Dodds H.L.
Publisher:Flogen Star OUTREACH
Publication Year:2016
Pages:390 pages
ISBN:978-1-987820-24-9
ISSN:2291-1227 (Metals and Materials Processing in a Clean Environment Series)
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    Overview Of Experimental Work At University Of Wisconsin On Molten Fluoride Salt In Fluoride Salt Cooled High Temperature Nuclear Reactors (FHRs)

    Huali Wu1; Raluca Scarlat2;
    1UW-MADISON, madison, United States; 2UNIVERSITY OF WISCONSIN-MADISON, madison, United States;
    Type of Paper: Regular
    Id Paper: 282
    Topic: 13

    Abstract:

    The Pebble-Bed Fluoride-Salt Cooled High Temperature Reactor (PB-FHR) is an advanced nuclear reactor concept design that combines high temperature and low pressure fluoride salt coolants with solid fuel elements containing encapsulated TRISO fuel particles. Compared to current commercial nuclear power plants operating with coolant temperature under ~ 400 C or below, which ends up running steam turbines with cycle efficiency below ~34%, coolant temperature in FHR is in the range of 600 C 700 C with high power conversion efficiency and power peaking capability by using an open-Brayton cycle can be achieved. This design takes advantage of the inherent and passive safety features enabled by heat transfer and chemical properties of fluoride salt and robust particle fuel. Working with fluoride salt has big challenges, such as, fluoride salts exhibit high melting point ~450 C, salt redox potential shows significant effects on coolant performance (corrosion, neutronic/thermal properties, etc.), interaction between salt and graphite fuel particle tends to affect fuel pebble integrity and potentially change salt redox potential. This article presents the research work pertaining to fluoride salt behavior with application to FHR design in University of Wisconsin-Madison, including a salt freezing experiment to investigate the solidification phenomena of fluoride salts, salt chemistry and electro-chemistry experiment to study applicability of current electrochemistry techniques to high temperature molten fluoride salts, and an experiment to study salt intrusion into graphite under various conditions (pressure, temperature, graphite surface finish). In the end, discussion about how the current research in UW-Madison will contribute to fluoride salt study for FHR design is presented.

    Keywords:

    Carbon; Materials; Moltensalt;

    References:

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    Cite this article as:

    Wu H and Scarlat R. Overview Of Experimental Work At University Of Wisconsin On Molten Fluoride Salt In Fluoride Salt Cooled High Temperature Nuclear Reactors (FHRs). In: Kongoli F, Gaune-Escard M, Turna T, Mauntz M, Dodds H.L., editors. Sustainable Industrial Processing Summit SIPS 2016 Volume 9: Molten Salts and Ionic Liquids, Energy Production. Volume 9. Montreal(Canada): FLOGEN Star Outreach. 2016. p. 41-50.