DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Review of molten salt reactor off-gas management considerations

Journal Article · · Nuclear Engineering and Design

Molten salt reactors offer a wide range of potential benefits but pose some unique challenges, particularly for designs that use an unclad liquid salt fuel. This type of fuel will result in the transport of fission gases into the headspace of the reactor where in some designs a cover gas can be circulated to remove certain fission products and maintain an inert atmosphere. The cover gas leaving the reactor core is expected to contain both noble and non-noble gases, aerosols, volatile species, tritium, radionuclides, and their daughters. To remove these radioactive gases, it is necessary to develop a robust off-gas system for molten salt–fueled reactors. Various treatment systems must be staged in series to remove the off-gas constituents from the stream before recirculating the gas back to the headspace of the reactor. Treatment options vary greatly depending on what they are designed to remove from the gas stream. This paper reviews the anticipated composition of a typical molten salt reactor off-gas stream and subsequently the available resources that could be employed to remove these species from the gas stream. An example off-gas system is then detailed, along with important design considerations, exemplifying the necessity for high-fidelity modeling. Lastly, the need for further thermophysical property research and the employment of advanced sensor technology for treatment component testing are discussed.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
Sponsoring Organization:
USDOE Office of Nuclear Energy (NE)
Grant/Contract Number:
AC05-00OR22725; AC05-76RL01830; AC07-05ID14517
OSTI ID:
1831663
Alternate ID(s):
OSTI ID: 1828223; OSTI ID: 1839945
Report Number(s):
PNNL-SA-161213; TRN: US2216613
Journal Information:
Nuclear Engineering and Design, Vol. 385; ISSN 0029-5493
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English

References (49)

Competitive I 2 Sorption by Cu-BTC from Humid Gas Streams journal June 2013
Functionalized Silica Aerogels: Advanced Materials to Capture and Immobilize Radioactive Iodine book September 2011
Conceptual Design Study of a Single-Fluid Molten-Salt Breeder Reactor report January 1971
An integrated model of tritium transport and corrosion in Fluoride Salt-Cooled High-Temperature Reactors (FHRs) – Part I: Theory and benchmarking journal December 2016
The rate of hydrogen release out of clean metallic surfaces journal September 1978
Development of New Waste Forms to Immobilize Iodine-129 Released from a Spent Fuel Reprocessing Plant journal October 2010
Molten salt reactor waste and effluent management strategies: A review journal April 2019
Purification of Inert Gas: Removal of Oxygen with a Metallic Getter journal January 1974
Adsorption equilibria of O2, Ar, Kr and Xe on activated carbon and zeolites: single component and mixture data journal February 2011
Graphene-based sorbents for iodine-129 capture and sequestration journal August 2015
Tritium Control and Capture in Salt-Cooled Fission and Fusion Reactors: Status, Challenges, and Path Forward journal February 2017
Studies on the permeation of Hydrogen and Tritium through heat resistant alloys journal April 1985
Tuning the structure and function of metal–organic frameworks via linker design journal January 2014
Nanoaerosols formation during the bubbling of lithium and beryllium fluorides molten salt to produce reactor radioisotopes journal December 2009
A Two-Column Method for the Separation of Kr and Xe from Process Off-Gases journal July 2014
Capture of Elemental and Organic Iodine from Dilute Gas Streams by Silver-exchanged Mordenite journal January 2016
Separation of systems based on uranium hexafluoride and some of halogen fluorides journal January 2009
Effect of gas flow rate on titanium sponge reaction
  • Wang, Zhiliang; Feng, Gaoping; Wang, Mingdong
  • GREEN ENERGY AND SUSTAINABLE DEVELOPMENT I: Proceedings of the International Conference on Green Energy and Sustainable Development (GESD 2017), AIP Conference Proceedings https://doi.org/10.1063/1.4992894
conference January 2017
Supermolecular Building Blocks (SBBs) for the Design and Synthesis of Highly Porous Metal-Organic Frameworks journal February 2008
Xenon Capture on Silver-Loaded Zeolites: Characterization of Very Strong Adsorption Sites journal July 2013
Verification of Modelica-Based Models with Analytical Solutions for Tritium Diffusion journal March 2018
Polyacrylonitrile-Chalcogel Hybrid Sorbents for Radioiodine Capture journal April 2014
Closed Fuel Cycle Waste Treatment Strategy report February 2015
Revised Phase Diagram of the System NaF–NaBF4 journal December 2007
Porous sorbents for the capture of radioactive iodine compounds: a review journal January 2018
Removal of Radioiodine from Gas Streams by Electrolytic Scrubbing journal September 1976
Silver-Loaded Aluminosilicate Aerogels As Iodine Sorbents journal September 2017
Absolute Band Intensity of the Iodine Monochloride Fundamental Mode for Infrared Sensing and Quantitative Analysis journal November 2020
Microporous Crystalline Membranes for Kr/Xe Separation: Comparison Between AlPO-18, SAPO-34, and ZIF-8 journal December 2017
MSR Fuel Salt Qualification Methodology report July 2020
Review of Hazards Associated with Molten Salt Reactor Fuel Processing Operations report June 2019
JUPITER-II molten salt Flibe research: An update on tritium, mobilization and redox chemistry experiments journal February 2006
Airborne waste management technology applicable for use in reprocessing plants for control of iodine and other off-gas constituents report February 1988
A Simple Model Predicting Iodine Profile in a Packed Bed of Silica-Gel Impregnated with Silver Nitrate journal March 2002
Materials and processes for the effective capture and immobilization of radioiodine: A review journal March 2016
The molten salt reactor (MSR) in generation IV: Overview and perspectives journal November 2014
Analysis of Krypton-85 Legacy Waste Forms: Part I journal September 2017
Market Basis for Salt-Cooled Reactors: Dispatchable Heat, Hydrogen, and Electricity with Assured Peak Power Capacity journal May 2020
Chalcogenide Aerogels as Sorbents for Noble Gases (Xe, Kr) journal February 2017
Modeling Tritium Retention in Graphite for Fluoride-Salt-Cooled High-Temperature Reactors journal January 2021
Particle Removal Efficiency of Gravitational Wet Scrubber Considering Diffusion, Interception, and Impaction journal March 2001
Capture of Volatile Iodine, a Gaseous Fission Product, by Zeolitic Imidazolate Framework-8 journal August 2011
Metal–organic framework with optimally selective xenon adsorption and separation journal June 2016
Quantitative measurement of beryllium-controlled redox of hydrogen fluoride in molten Flibe journal February 2006
Compatibility of technologies with regulations in the waste management of H-3, I-129, C-14, and Kr-85. Part I. Initial information base report August 1983
Metal–Organic Frameworks as A Tunable Platform for Designing Functional Molecular Materials journal August 2013
Applicability of a Model Predicting Iodine-129 Profile in a Silver Nitrate Silica-Gel Column for Dissolver Off-Gas Treatment of Fuel Reprocessing journal January 2003
Breakthrough in Xenon Capture and Purification Using Adsorbent-Supported Silver Nanoparticles journal June 2016
Iodine Confinement into Metal–Organic Frameworks (MOFs): Low-Temperature Sintering Glasses To Form Novel Glass Composite Material (GCM) Alternative Waste Forms journal May 2011