NC2
Nuclear Consulting Company
Thorium Conference, CERN
Didier.haas@hotmail.be
++32 491648840

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T. Lung: EURATOM report 1777 (1997)
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THOR Energy Thorium Fuel Conference, Paris (2010)
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IAEA No NF-T-2.4 (2012): The role of Thorium to supplement Fuel
Cycles of Future Nuclear Energy Systems
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GIF position paper on the use of Thorium in the Nuclear Fuel
Cycle (2010)
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SNETP Strategic Research and Innovation Agenda (2013) and
SRA Annex on Thorium (2011)
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Published EURATOM Framework Programmes results and personal communications
Thorium Conference, CERN

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European Research on Thorium
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Thorium in HTRs
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Thorium oxide fuel behaviour
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Molten salt reactors fueled with Thorium
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Conclusion
Thorium Conference, CERN

Launched in 2007
117members from research, industry, academia, technical safety organizations
Recent application of
Weinberg Foudation (UK) and
ThorEA (UK) both promoting
Thorium research
Produced a Research Agenda
(2009, revised in 2013) and a
Deployment Strategy (2010)

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SNETP has produced an Annex (2011) on Thorium in the Strategic
Research Area. Highlights are:
LWRs: evolutionary development favoured, with use of Pu as seed (natural U savings); breeding would need new reactor technology
HWRs: high conversion ratio achievable
HTR: past German HTR development programme aimed at reaching a breeding cycle with Thorium
Fast Reactors: breeding possible but with long doubling times; improved void reactivity coefficient in sodium FR; advantage of
ADS subcritical reactor (high neutron energies, Th 232 fission + captures)
MSR: breeding might be achieved over a wide range of neutron energies; long-trerm development option
Pu-burning: Thorium matrices for the purpose of incinerating Pu in LWRs
Challenges for solid fuels: reprocessing, remote fuel fabrication
Thorium Conference, CERN

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1960-1980: limited experimental work on Thorium use in
HTRs (DRAGON, ATR, THTR, Th-U carbide and oxide fuels) and in the Lingen BWR by SIEMENS (Th-MOX)
1990-2002: Assessment studies including the « Lung report » and the EURATOM projects « Thorium Cycle as a nuclear waste management option » and « Red Impact »
1998-2008: Thorium fuel experiments (Projects THORIUM
CYCLE, OMICO, LWR-DEPUTY with irradiations in KWO-
Obrigheim, HFR and BR2)
FP7 (2011-13): Performance assessment of Thorium in geological disposal (SKIN Project)
FP5-FP7 (1998-now): Thorium fuel studies and characterization for a Molten Salt Reactor (Projects MOST,
ALISIA, EVOL…)
Thorium Conference, CERN

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HTR thermal neutron spectrum is very well suited for
Thorium breeding
Very high burnup capability in HTRs in a once-through cycle; very high stability in geological disposal of the
Thorium matrix
This explains the (successful) use of Thorium in early HTR projects (DRAGON, AVR Jülich, Peach Bottom, Fort St-
Vrain, THTR); fresh fuel kernels were mixed with Pu or
U235 fissile material
Potential limitations are the high initial U235 content needed in the once-through strategy and the reprocessing difficulty in case of closed cycle strategy
Today, (V)HTR is one of the six GIF R&D systems;
European interest in HTR exists, but difficulty in getting industry commitments
Thorium Conference, CERN

Thorium Conference, CERN

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ThO2 is a very stable ceramic: in-core applications, direct disposal waste management (see leaching tests results from JRC-ITU Karlsruhe)
Th-MOX (Th,PuO2) has been contemplated to incinerate separated Pu in LWRs in a fertile matrix, and also as possible « quasi »-inert matrix for MA burning in
« targets »
The Th matrix produce no new Pu and is fertile as required to keep the reactivity in LWRs
In-reactor properties are equivalent (even better if one considers the thermal behaviour and the stability) to U-
MOX
Thermal diffusivity measurements on unirradiated Th-
MOX at JRC-ITU: higher than U-MOX
Thorium Conference, CERN

FP5: THORIUM Cycle for P&T and ADS
PARTITIONING (5 MEuro)
PYROREP
PARTNEW
CALIXPART
TRANSMUTATION (3.9 MEuro)
Fuels:
CONFIRM
THORIUM CYCLE
FUTURE
TRANSMUTATION (6 MEuro)
Preliminary Design Studies for an Experimental ADS:
PDS-XADS
FP5 ADOPT
Coordination Network
TRANSMUTATION (6.5 MEuro)
Basic Studies:
MUSE
HINDAS
N-TOF_ND_ADS
TRANSMUTATION (7.3 MEuro)
Technological Support:
SPIRE
TECLA
MEGAPIE-TEST
ASCHLIM
EUROTRANS FP6 Project
FP5 (1998-2002) Projects on Advanced Options for Partitioning and Transmutation

Associated Project on
Advanced P&T Fuels:
LWR-DEPUTY Project with Thorium fuels
Inert Matrices fuels
Thorium Conference, CERN

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Experiments
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(Th,Pu)O
2
 fuels were irradiated in three reactors
HFR-Petten (Na-capsule)
 KWO Obrigheim (non-instrumented, commercial PWR)
 BR-2 Mol (instrumented & non-instrumented in PWR loop)
Post-irradiation examinations & radiochemistry by different labs (ITU, NRG, PSI, SCK•CEN)
12

Safety assessment of Plutonium Mixed Oxide Fuel irradiated up to 37.7 GWd/tonne (JNM 2013)
J. Somers1,*, D. Papaioannou1, J. McGinley1, D.
Sommer2
1. Joint Research Centre
–
Institute for
Transuranium Elements, Postfach 2340, D76125
Karlsruhe, Germany
2. EnBW Kernkraft GmbH*, Postfach 1161, 74843
Obrigheim and Böhmerwaldstraße 15, 74821
Mosbach, Germany
Thorium Conference, CERN

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From:
C. Cozzo et al., J. Nucl. Mater. (2011), doi:10.10C. Cozzo et al., J. Nucl. Mater. (2011),
Thorium Conference, CERN

Th-MOX Thermal Conductivity as compared to U-MOX
6.0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
UO
2
ITU
UO
2
Fink
Homogeneous MOX
11.1 wt. % PuO
2
9.0 wt. % PuO
2
5.6 wt. % PuO
2
4.8 wt. % PuO
2
C. Cozzo et al., J. Nucl. Mater. (2011), doi:10.10C. Cozzo et al.,
J. Nucl. Mater. (2011),
Heterogeneous MOX
9 wt. % Pu
7 wt. % Pu
MOX Duriez
600 800
At 1000K TC of U-MOX: 3.0-3.5
of Th-MOX: >4.0
!! Importance of the fabrication process
1000 1200 1400 1600
Temperature, K D. Staicu, M. Barker, J. Nucl. Mater. (2013), http://dx.doi.org/10.1016/j.jnucmat.2013.08.024
Thorium Conference, CERN

1600
1400
1200
OMICO Rod Gi
2000
1800 power calibration from Dec 2006 measurement
MACROS (post-test)
Transuranus (post-test)
(mod. fuel deformation)
Transuranus (blind)
Copernic
1000
800
600
0 2000 4000 6000
Time (h)
16
8000
Personal communication
By courtesy of SCK-CEN

Source: Rondinella & Al (JRC-ITU)
Paris Thorium technical meeting 2010
Thorium Conference, CERN

Reference case: SKB spent fuel repository
Thorium Conference, CERN
Bx, Gx: compartments of Bentonite, Granite

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No showstoppers identified for Thorium-based MOX
(Th,Pu)O
(Th,Pu)O
2 to its implementation as a possible LWR-fuel. has several advantages over Uranium-based
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2
Better thermal conductivity (unirradiated data only)
Improved chemical stability
Indications for improved reactivity margins for full-core PWR
(Th,Pu)O
2 compared to (U,Pu)O
2
Next steps:
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Improving the fuel manufacturing technology, since the scoping studies used non-industrial (& non-industrialisable) manufacturing routes; tests on representative fabrications needed
Larger-scale demonstration programs with lead-rod and leadassembly irradiations are needed before licensing
Personal communication
By courtesy of SCK-CEN
19

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In MSRs thorium cycle can achieve a higher conversion ratio than the uranium/plutonium cycle.
MSR avoids some of the loss of conversion efficiency that occurs due to neutron capture events in Pa-233 (Pa-233 has a relatively long half-life of 27 days). The nuclear fuel in MSR is unique in that it circulates through the entire primary circuit and spends only a fraction of its time in the active core. This reduces the time-averaged neutron flux that the Pa-233 sees and significantly reduces the proportion of Pa-233 atoms that are lost to neutron captures
MSR continually reprocesses the nuclear fuel as it re-circulates in the primary circuit, removing fission products as they are generated. MSR therefore completely avoids the difficulties in conventional reactors with fabricating U-233 fuels (which have high gamma activities from U-232 daughters).
Since the nuclear fuel is a molten salt, there are no fuel mechanical performance issues to consider.
Thorium Conference, CERN

From MOST to EVOL
A continuous and coordinated activity (European network) since 2001
MOST
LICORN
ALISIA
SUMO
EVOL
2001-2003
Confirmation of MSR potential
Identification of key issues (vs MSBR)
2004-2006
Strenghthening of European network
Follow-up of R&D progress
2007-2008
Review of liquid salts for various applications
Preparation of European MSR roadmap
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2009
 Feasibility demonstration of MSFR
2009-2012
Optimization of MSFR
(remaining weakpoints)
Thorium Conference, CERN
6 countries +
Euratom from
MSBR
7 countries +
Euratom
+ Russia
7 countries +
Euratom
+ Russia
8 countries +
Euratom
+ Russia
7 countries +
Euratom
(+ Russia)
… to
MSFR

Strategic impact of EVOL
A common European Molten Salt Reactor concept for GENIV
(major European contribution to the MSR GENIV initiative)
Thorium as a nuclear fuel
(closed MSR fuel cycle, sustainable energy system)
Partitioning & Transmutation
(alternative route for P&T compared to solid fuel)
Improved understanding of liquid salt properties
(MSR technology, but also other industrial processes)
Thorium Conference, CERN

MSFR reactor concept (French concept)
(Molten Salt Fast Reactor)
Initial MSFR fuel composition:
X(LiF) = 77.45 mol%
X(ThF
4
) = 20 mol% (LiF-ThF
4 eutectic)
X(UF
4
) = 2.55 mol%
Operating temperature: T inlet
= 620 °C
MSFR pre-conceptual design,
GIF Annual Report 2009: (MSR)

Molten Salt Database developed at JRC (ITU)
(2002-2010): 38 assessed binary systems
Thorium Conference, CERN

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Several EC Projects on Th-MOX fuels mainly for LWRs as « Quasi »-Inert matrix to burn Pu and MAs
Thorium salts as fuel for the MSR
The SRIA published in 2013 recognises the
« significant long-term potentialities and the significant challenges to make industrial implementation » of Thorium systems
Thorium Conference, CERN

With particular thank to Michel Hugon and Roger Garbil (EC DG
RTD, Brussels), Vincenzo Rondinella, Dragos Staicu, Joe Somers (EC
JRC, ITU, Karlsruhe) and Marc Verwerft (SCK-CEN) for their assistance in providing all relevant information and comments.
Thorium Conference, CERN