Transcript Fluoride technologies for advanced nuclear reactor systems

Fluoride Technologies for Advanced Nuclear
Reactor Systems
Jan Uhlíř
Nuclear Research Institute Řež plc
Czech Republic
[email protected]
Innovative nuclear concepts,
Liblice, Czech Republic, April 10 – 12, 2012
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Main Fluoride Processes in Nuclear Technology
Uranium enrichment (diffusion technology, centrifugation technology)
 Production of UF4
 Production of UF6
Pyrochemical reprocessing of spent nuclear fuels
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Fluoride volatility method,
Fused salt volatilization,
Electrochemical separation from molten fluoride media,
Molten salt / liquid metal extraction
Molten Salt Reactor technology
 Liquid fuel processing (UF4, ThF4), On-line reprocessing
Fluoride-cooled High-temperature Reactor technology
 FLIBE coolant technology (FLIBE = 7LiF-BeF2)
 High-temperature heat transfer (fluoride salts – FLIBE type)
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Main Czech activities and R&D projects containing fluoride
technologies
MIT project: “Nuclear system SPHINX with molten fluoride salts
based liquid nuclear fuel” (2004 - 2008)
 R&D project devoted to MSR technology covering theoretical and
experimental activities in MSR physics, fuel cycle chemistry, molten salt
thermohydraulics, structural material development and testing of
apparatuses for molten fluoride salt media
MIT project: “Fluoride reprocessing of spent fuel of GEN-IV
reactors” (2006 – 2011)
 R&D project devoted to pyrochemical fuel cycle technologies focused
mainly to fluoride separation processes suitable for MSR technology
including thorium - uranium fuel cycle and separation of transuranics
Projects focused on electrochemical separation technologies
supported and/or coordinated by RAWRA and EC-EURATOM
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Mission and objectives
of Fluoride Volatility Method
Reprocessing of such types of oxide fuels from LWR or FR, which
could be hardly reprocessed by aqueous (hydrometallurgical)
technologies (inert matrix fuels, TRU-fuels, fuels with very high
burn-up, short cooling time, high concentration of Pu, different
cladding material etc.)
Reprocessing of metallic and/or carbide fuels
Primary processing of TRU-fuel for MSR – An-burners
Objectives of FVM:
Separation of a maximum fraction of uranium component from Pu,
MA and FP.
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Principles of reprocessing
by Fluoride Volatility Method
The technology is based on direct fluorination of spent fuel by
fluorine gas.
The separation process comes out from the specific property of
uranium, neptunium and partially of plutonium to form
volatile hexafluorides, whereas most of fission products and
transplutonium elements present in spent fuel form nonvolatile trifluorides.
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Process flow-sheet of Fluoride Volatility Method
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Present R&D:
Experimental technological line FERDA in NRI Řež plc
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Experimental Technological Line FERDA in the NRI Řež plc
V2.1
V3.2
V4.2
V6.2
F5
V1.7 V1.7-R
V1.10 V1.10-R
V1.9 V1.9-R
F7 F3 F6 F4
V1.8 V1.8-R
T6.1
V6.1
D7
K6
R1
K2
K3
C5
K4
V9.1
0.17MPa
EPP
P-R
V8.1-R
H8
V8.17
V8.10
V8.16
V8.9
V8.15
V8.8
V8.14
V1.6
V8.7
TL-N 2
V8.6
F1
V8.2
TL-VZDUCH
V8.3
V8.4
V8.5
Vývěva
V8.11
F2-R
O7
T7.1
T4.1
T6.2
O5
T2.1 T3.2
V4.1
O6
V3.1
T3.1 T4.2
T5.1
T2.2
O2
T1.11
T1.9
HT2
O4
T1.10
T1.6 T1.8
T1.7
V1.10-S
T1.4
O1.2
T1.3
O1.1
RJ
T1.2
O1.3 T1.5
T1.1
O3
V1.5
V1.4-R
D9
V1.3
V1.2
V1.2-S
HT1
V8.13
V8.12
V1.1
Vy10
TL-F2
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Current status – future plans
Basic demonstration of FVM was verified
Further engineering development and verification with
irradiated fuel is necessary:
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To prepare a collaborative project with U.S.-DOE
laboratories
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To solve the input steps of FVM: decladding, voloxidation,
final preparation of fuel for dosing
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To solve plutonium management
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To solve U – Np purification
Verification with irradiated fuel - hot cell technology
Industrialization of the technology
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Prospects of Fluoride Volatility Method
Fluoride Volatility Method has a good potential to be used within
the fuel cycles of advanced reactor types for reprocessing of
selected advanced oxide fuel types, metallic and carbide
fuels.
The main attractiveness of the technology is in the extreme
radiation resistance of used chemical agents (fluorine gas,
inorganic fluorides), non presence of any neutron moderating
agents and in the possible compactness of the whole
process.
The technology is compact and can be designed to be highly
proliferation resistant.
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R&D on Electrochemical separation of An/Ln
from molten fluoride media
The R&D is still at laboratory level.
Development of separation technology suitable for on-line
reprocessing of MSR fuel
Carrier salt of MSR primary (fuel) circuit:
7LiF-BeF (called FLIBE) or 7LiF-BeF -NaF
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Carrier salts proposed for electrochemical separation processes:
7LiF-BeF or 7LiF-BeF -NaF
(limited use)
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2
LiF-NaF-KF (called FLINAK)
LiF-CaF2
Electrochemical separation processes under development:
Cathodic deposition method
Anodic dissolution method
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Laboratory research on electrochemical separation
from fluoride molten-salt media
 The electrochemical measurements have
been carried out in a laboratory nickel
electrolyser under inert atmosphere in a
three-electrode set-up.
 A specially designed reference electrode
based on the Ni/Ni2+ red-ox couple was
developed.
 Linear Potential Sweep Cyclic Voltammetry
Method has been used as the
measurement technique.
700
j [mA/cm2 ]
350
0
Flibe+UF4
-350
Flibe
-700
-1800
-1200
-600
0
E [mV]
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Flow-sheeting of MSR on-line reprocessing technology
 The flow-sheet concepts comes out from the former results achieved by
ORNL team during MSRE and MSBR projects and from the current
progress in fluoride electrochemical separation studies
 The reprocessing technology design is based on primary total (nonselective) “Molten-salt / Liquid metal” reductive extraction from MSR
carrier salt and on subsequent electrochemical separation processes:
– Anodic dissolution method (selective electrochemical oxidation of
reduced elements according to the differences in their red-ox
potentials)
– Cathodic deposition method - electrorefinning (selective
electrochemical reduction of dissolved ions in molten carrier salt)
MSR – Th-breeder:
 One-fluid vs. Two-fluid system of MSR core design and corresponding
flow-sheets
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Conceptual flow-sheet of MSR on-line reprocessing technology
One-fluid system
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MSR fuel processing
Production of pure uranium tetrafluoride UF4 and thorium
tetrafluoride ThF4 for MSR liquid fuel processing
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Proposal of US – Czech collaborative R&D
on FHR/MSR systems (ORNL/UCB/MIT/NRI)
Mutual interest was expressed in 2008
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Memorandum of Agreement between UT-Battelle LLC and NRI was concluded in
December 2009
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Joint declaration between US-DOE and Czech Ministry of Industry and Trade
opened doors for the intergovernmental collaboration in civil nuclear R&D
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 April 2011: U.S. – Czech Republic Civilian Nuclear Energy Experts Meeting
 June 2011: Dr. Peter Lyons visited NRI to be informed about the status
 September 28th 2011: Dr. Daniel Poneman visited Prague to announce the
U.S. – Czech program in nuclear R&D
 October 27th 2011: Czech Prime Minister Nečas and US President Obama
came to agreement on civil nuclear collaborative R&D
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 January 2012: US – Czech technical experts workshop to launch
collaborative projects in molten salt and fluoride volatility technologies
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However we are not alone in the development of MSR and
fluoride technologies
 January 2011, China announced ambitious TMSR program under
the leadership of Dr. Jiang Mianheng – the Vice President of CAS.
At present, India announced similar Thorium MSR program to launch in
2013.
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Thank you for your attention
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