This document is an excerpt from the EUR-Lex website
Document 52011SC0929
COMMISSION STAFF WORKING PAPER Accompanying document to the Report "Operation of the High Flux Reactor in year 2009"
COMMISSION STAFF WORKING PAPER Accompanying document to the Report "Operation of the High Flux Reactor in year 2009"
COMMISSION STAFF WORKING PAPER Accompanying document to the Report "Operation of the High Flux Reactor in year 2009"
/* SEC/2011/0929 final */
COMMISSION STAFF WORKING PAPER Accompanying document to the Report "Operation of the High Flux Reactor in year 2009" /* SEC/2011/0929 final */
COMMISSION STAFF WORKING PAPER Accompanying document to the Report
"Operation of the High Flux Reactor in year 2009"
1.
Introduction
This staff working document is a companion
document to the Report from the Commission to The Council and the European Parliament
"Operation of the High Flux Reactor in year 2009" The High Flux Reactor (HFR) Petten, managed
by the Institute for Energy (IE) of the JRC of the European Commission, is one
of the most powerful multi-purpose materials testing reactors in the world. The HFR is of the tank-in-pool type, light
water cooled and moderated and operated at 45 MW. In operation since 1961, and
following a new vessel replacement in 1984, the HFR has a technical life beyond
the year 2015. The reactor provides a variety of irradiation facilities and
possibilities in the reactor core, in the reflector region and in the poolside.
Horizontal beam tubes are available for research with neutrons and gamma
irradiation facilities are also available. Furthermore, excellently equipped hot
cell laboratories on the Petten site provide virtually all envisaged
post-irradiation examinations possibilities. The close co-operation between JRC and the
Nuclear Research and consultancy group (NRG) on all aspects of nuclear research
and technology is essential to maintain the key position of the HFR amongst
research reactors worldwide. This co-operation has led to a unique HFR
structure, in which both organisations are involved. Euratom is the owner of
the plant (for a lease of 99 years) and the JRC the plant and budget manager.
JRC develops a platform around HFR as a tool for European collaborative
programmes. NRG operates and maintains the plant, under contract, for JRC and
manages the commercial activities around the reactor. The Mo-99 isotope production was increased
to a level around 180% of normal production (exceeding the radiochemical
processing capacity available within the European supply network) to compensate
the unexpected shutdown of the NRU Reactor in Canada. The HFR produced enough
material to allow more than 50,000 patient scans per day to be performed
worldwide which represented around 60% of the normal total world demand. As of February 2005 NRG has become the
holder of the operation licence granted under the Dutch Nuclear Energy Law. Furthermore
each organisation provides complementary possibilities around the reactor
activities, such as the hot cell facilities of NRG or the experiment
commissioning laboratory of JRC. During
the last three decades the HFR has been operated from Supplementary Programmes
regularly discussed by the European Council. On 25 May 2009, the European
Council adopted a three-year supplementary research programme to be implemented
by the Joint Research Centre for the European Atomic Energy Community
(2009-2011) concerning the operation of the Community’s High Flux Reactor. The present document aims at reporting the
implementation of the above scientific and technical objectives in 2009, first
year of the current Supplementary Programme. The report also provides information
regarding the financial contributions received for the execution of the
programme and the yearly contribution to the decommissioning fund that the
supplementary programme provides to the Euratom, owner of the HFR.
1.
HFR: Reactor Management
HFR Safety, Operation and Related Services The HFR reactor is operated by NRG. It has
an operating licence granted by the Dutch national regulator, the Kernfysische Dienst (KFD). As for nuclear
power plants, the HFR is subject to legally required 10-year periodic reviews
which are performed by NRG. The HFR has been also the subject of an independent
IAEA INSARR (Integrated Safety Assessment for Research
Reactors) review in March 2005, and the next is foreseen in 2011. At the start of 2009, all the
investigations and inspections of the bottom plug liner showed clearly that a
safe start and subsequent operation, under strict conditions, of the HFR were
possible. Due to increasing shortage of radioisotopes and on urgent request of
the radioisotopes producers, authorization was given by the Dutch competent
authorities to operate the HFR.The planned operational cycle pattern consisted
of a scheduled number of 249 operation days and two maintenance periods of
respectively 42.6 and 31.3 days. In 2009 therefore, the HFR was in operation
for 248 days. The reduction of operating time can be
almost completely attributed to the investigation and inspections of the bottom
plug liner which caused the extended shutdown and the later start of HFR
cycle 09.02. After deliberation between physicians and on request of the major
radioisotope producers, the maintenance period between HFR cycle 2009-01 and
HFR cycle 2009-02 was extended to 31 March 2009. The objective of this change
of cycle pattern was to ensure the availability of sufficient irradiation
capacity at the end of cycle 2009-02. This corresponds to an actual
availability of 67.97 % with reference to the scheduled operation plan. Nominal
power has been 45 MW, with a total energy production of approximately
11 135.21 MWd, corresponding to a fuel consumption of about 13.9 kg 235U. At the beginning of the reporting period,
HFR operations were temporarily stopped due to the final part of the investigation
and inspection of the bottom plug liner and the performance of the annual
containment leak test. Nevertheless, all the 2009 cycles were started according
to the original schedule. During the summer maintenance period, the extended
reactor vessel inspection of the bottom plug liner and several safety related
modifications were successfully performed. After the scheduled end of each
cycle, the shut-downs included activities performed in the framework of the
regular HFR operators’ training. The detailed operating characteristics for
2009 are given in Table 1. All details on power interruptions and power
disturbances are given in Table 2. It shows that 5 scrams and one manual power
decrease occurred. Two of these scrams were due to manual intervention and a
human error respectively. Two others were caused by loss of off-site power. The
remaining scram was due to intervention of the reactor instrumentation devices
to ensure safety. Besides the regular visits of international
colleagues and relations with the medical world, a total of 914 visitors
(divided over 162 tours) were guided through the reactor during 2009. In 2009, the maintenance activities
consisted of the preventive, corrective and breakdown maintenance of all
Systems, Structures and Components (SSCs) of the HFR as described in the annual
and long term maintenance plans. These activities are executed with the
objective to enable the safe and reliable operation of the HFR and to prevent
inadvertent scrams caused by insufficient maintenance. The periodic leak testing, as one of the
licence requirements (0.2 bar overpressure for 24 hours duration) and the
extended In-Service Inspection, including measurements on the bottom plug
liner, were performed successfully. As part of the HFR Modification Plan,
several modifications were completed. All modifications were implemented after
the revision of the plant description and operating instructions and following
successful commissioning and testing. Table 1: 2009
operational characteristics Table 2 :
2009 full power interruption of HFR Fuel Cycle During 2009, due to the shutdown of the
HFR, only 5 Low Enriched Uranium (LEU) fuel elements and 4 control rods were
inspected at the manufacturer’s site and delivered to Petten. Since May 2006,
the HFR is running completely on LEU fuel. In 2009, two shipments with High Enriched
Uranium (HEU) spent fuel took place in MTR2 containers to the Dutch Central
Organisation for Radioactive Waste (COVRA); in total 66 elements, of which 59
fuel and 7 control rods, equivalent to two positions in the HABOG building for
High Level Radioactive waste at COVRA. At the end of 2009, 26 positions out of
the 48 positions (including the 6 reserve positions) are vacant in the HABOG.
The last 18 HEU elements, still present in the HFR pool, are planned to be
shipped in 2010. The Gesellschaft für Nuklear-Service (GNS)
carried out the compulsory 3 years inspection of the shock absorbers which are
mounted around a loaded cask during a transport. The shock absorbers needed a
second inspection which required the building of a special device that prevents
deformation during the pressure test.
2.
HFR Supporting Networking in Research
2.1.
Network on Neutron Techniques Standardization
for Structural Integrity (NeT)
NeT, the European Network on Neutron
Techniques Standardization for Structural Integrity, supports progress towards
improved performance and safety of European energy production systems. To this
end, the JRC, next to its role as manager of NeT, contributes to the scientific
work through neutron scattering for residual stress measurement and assessment
of thermal material ageing effects, using its beam tube facilities at the HFR.
In addition, in 2009, the JRC started its contributions to synchrotron X-ray
diffraction measurements performed at synchrotron facilities in France and
Germany. About 35 organisations are actively
participating in the work of NeT, including eight organisations from the new
member states, three organisations from candidate countries, one from Russia,
one from Japan, one from Australia, and one from South Korea. In 2009, the NeT
Steering Committee met twice and significant progress has been made in carrying
out the work within its Task Groups (TGs). In November 2009, an Enlargement and
Integration Workshop has been organised attended by about 15 scientists from
the EU and Turkey. In 2009, the main experimental activities
in NeT were within the newly established TGs 4 and 5. TG4 focused on a 3-bead
in a slot weld in a stainless steel plate while TG5 dealt with an autogenous
weld along the edge of the ferritic steel beam. Several contributors, including
JRC, provided experimental assessment of welding residual stresses and welding
distortion for these specimens. Based on the work performed in TG1 on a
single bead weld on a plate, a dedicated issue of the International Journal of
Pressure Vessels and Piping has been published in 2009. It includes, among
others, 14 papers from the participants of NeT. NeT TG1 is now also becoming an
example case in the weld modelling section of the R6 defects assessment
procedure in the UK, and it has also been suggested to be considered as a
sample case for a NAFEMS numerical analysis standard for welding residual
stresses. In the course of 2009, first contacts have
been established with the US Nuclear Regulatory Commission (NRC), to the IAEA
and to the International Institute of Welding (IIW) with a view to assessing
the possibilities for a future involvement of these organizations in NeT. The HFR irradiation possibilities were used
to perform residual stress measurements by neutron diffraction, as explained in
the next chapter.
2.2.
FAIRFUELS, towards a more sustainable fuel cycle
with less nuclear waste
In the frame of the EURATOM 7th
Framework Programme (FP7), the 4‑year project FAIRFUELS (Fabrication,
Irradiation and Reprocessing of FUELS and targets for transmutation) aims at a
more efficient use of fissile material in nuclear reactors by implementing
transmutation. Transmutation provides a way to reduce the volume and hazard of
high level radioactive waste by recycling the most long-lived components. In
this way, the nuclear fuel cycle can be closed in a sustainable manner. The
FAIRFUELS consortium consists of ten European research institutes, universities
and industry. The project started in 2009 and is coordinated by NRG. Both NRG
and JRC-IE work closely together on the HFR irradiations that are scheduled in
FAIRFUELS: MARIOS and SPHERE fuel irradiations, as described in the following
chapters.
3.
HFR as a Tool for Research
3.1.
Residual Stress Measurements by Neutron
Diffraction at the HFR
In 2009, the HFR facilities for residual
stress measurement by neutron diffraction at beam tubes HB4 and HB5 have been
used for a number of measurement campaigns. Three examples are outlined
briefly, as follows: In the context of NeT Task Group 5 (see
above), residual stress/strain measurements have been performed across the
width of a 10 by 50 mm2 cross section ferritic steel beam with an
autogenous weld along one of its edges. These measurements are part of a TG5
residual stress measurement round-robin, where the experimental results shall
aid the validation of numerical stress prediction procedures. Indeed,
prediction procedures are complicated in the case of such ferritic steels
because of the involvement of phase transformations during various stages of
the welding process. A second series of measurements, performed
in 2009, targeted developments of improved measurement procedures for
multi-pass welds in stainless steel, as they are often used in assembling
primary cooling systems in nuclear power installations. The inhomogeneity of the
weld material and the sheer size of such components complicate significantly
the experimental determination of the welding residual stresses. The specimens
used in these measurements were slices cut from a bi-metallic – ferritic to
austenitic steel – piping weld whereby, in this case, a stainless steel clad
layer was applied on the inner surface of the ferritic part of the pipe.
Finally, an IAEA driven collaborative research project (CRP), with
participation of the JRC, on research reactors and the capabilities for
residual stress measurement has been concluded in 2009. The JRC assumed
responsibility for the organization of ongoing round robin exercises to
benchmark the performance of the participating facilities. Nine or ten reactor
based neutron sources are expected to participate in the round robin exercises
within the coming one or two years. The contribution of the HFR to this first
round robin exercise (an interference fit of an aluminium ring and plug) has
been performed in spring 2009. This round robin reiterates a corresponding
exercise in the context of VAMAS TWA20 in the late 1990’s (see also HFR annual
report 1998), and the data from 2009 are in good agreement with those measured
at that time. In 2009, NRG has also continued to perform
structural analyses by powder diffraction using the diffractometer of beam tube
HB3a. Among others, materials for electricity storage applications have been
investigated upon request of Leiden University. On the same instrument, a
powder diffraction spectrum of lithium hydride, a candidate material for
hydrogen storage, was measured on behalf of the JRC Cleaner Energies Unit
3.2.
CRYO Experiment: Alpha-Emitters Radiotoxicity
Reduction
Research conducted to date tends to suggest
that the decay half-life of alpha-emitting isotopes embedded in a metallic
matrix may be reduced at cryogenic temperatures. If confirmed, this may
ultimately contribute to the reduction of nuclear waste. To avoid any possible speculations, JRC is
trying to verify the status/outcome of these studies by conducting an
experiment in the HFR, called CRYO. The CRYO irradiation will produce 210Po,
which is a pure alpha emitter, embedded in a metallic matrix of copper. This
will be achieved by the irradiation of eight copper – bismuth disks and
transmutation of 209Bi. Irradiation of the CRYO experiment started
on 22 December 2009, for a duration of one HFR cycle (~29 full power days).
4.
Fuel Irradiations in the HFR
4.1.
HELIOS Fuel Experiment: Americium Transmutation
Americium is one of the radioactive
elements that contribute to a large part of the radiotoxicity of spent fuels.
Transmutation, by irradiation in nuclear reactors of long-lived nuclides such
as 241Am, is therefore an option for the mass and radiotoxicity
reduction of nuclear wastes. The Helios experiment, as part of the FP6
EUROTRANS Integrated Project on Partitioning and Transmutation, deals with
irradiation of U-free fuels containing americium. The main objective of the
HELIOS irradiation is to study in-pile behaviour of U-free fuel targets, such as
CerCer (Pu, Am, Zr)O2 and Am2Zr2O7+MgO
or CerMet (Pu, Am)O2 +Mo, in order to gain knowledge on the role of
microstructure and temperature on gas release and on fuel swelling. During the
irradiation, a significant amount of helium is produced by the transmutation of
americium. The gas release study is of vital importance to allow better
performance of the U-free fuels. Two different approaches are followed to reach
early helium release: 1. Provide release pathways by creating
open porosities, i.e. release paths to the plenum gas. Therefore, in the HELIOS
test matrix a composite target with a MgO matrix containing a network of open
porosity has been included. 2. Increase target temperature to promote
the release of helium from the matrix. Americium or americium/plutonium
zirconia based solid solutions along with CerMet targets have been included in
the test matrix to study the effects of the temperature. Adding plutonium
allows for fission, which will increase the target temperature at the beginning
of irradiation (BOI). Irradiation of the HELIOS experiment
started on 29 April 2009 and lasted about 250 full power days, i.e. until the
HFR stop, on 19 February 2010. The start-up of the experiment has been
flawless. During the first cycle, the experiment has showed a higher neutron
flux than expected. Investigations are being conducted and will be finalised
with the measurement of the fluence detectors installed near to each test pin.
This higher flux does not jeopardise the results of the experiment. As a matter
of fact, it might even help as the experiment will receive more neutron fluence
than expected. This will counteract the premature stop by raising the burn-up
and helium production.
4.2.
MARIOS Fuel Irradiation: Minor Actinide
Recycling
The MARIOS
irradiation programme, as part of FAIRFUELS, is a series of irradiations
dealing with heterogeneous recycling of Minor Actinides (MAs) in Sodium-cooled
Fast Reactors (i.e. the MA-bearing-blanket concept). MAs, such as americium and
curium, are not always recycled and remain key elements composing the waste.
The aim of the MARIOS irradiation is to investigate the behaviour of MA targets
in a uranium oxide matrix carrier. For the first time, americium (241Am)
is included in a (natural) uranium oxide matrix Am0.15U0.85O1.94.
This irradiation will produce large amounts of helium within the targets. Its
goal is therefore to study the fuel behaviour in terms of helium production and
swelling. These may cause significant damage to the material under irradiation.
The MARIOS irradiation will start in autumn 2010 and will last for
approximately 300 full power days. During 2009, the preliminary design of
MARIOS was finalised. The nuclear analyses have been concluded and the fission
power generated by the fuel pellets has been calculated. The fuel pellets, made
by CEA in France, are in preparation and will arrive in Petten during spring
2010.
4.3.
SPHERE Fuel Irradiation: Safer Fuels
Within the FP7 FAIRFUELS project, the
irradiation SPHERE has been planned for 2011. SPHERE has been designed to
compare conventional pellet-type fuels with so-called sphere-pac fuels. The
latter have the advantage of an easier, dust-free fabrication process. When
dealing with highly radioactive minor actinides, dust-free fabrication
processes are especially essential to reduce the risk of contamination. To assess the irradiation performance of
Sphere-Pac fuels compared to conventional pellet fuel, a dedicated SPHERE
irradiation experiment will be performed. For this purpose,
americium-containing fuel, both pellet and sphere-pac types, will be fabricated
at JRC-ITU in Germany. These fuels will be irradiated in the HFR. This
irradiation is the first of its kind, as no minor actinide bearing Sphere-Pac
fuel has ever been irradiated before. The SPHERE irradiation will last for
approximately 300 full power days. The preliminary design for the SPHERE
irradiation experiment has started and the first fabrication trials have
started.
4.4.
HTR Fuel Pebble Irradiation HFR-EU1
After a pause of several years, after the
end of the German fuel qualification programme, JRC-IE resumed in 2004 new HTR
fuel irradiations in the HFR, this time with a focus on determining the limits
of old and newly produced fuel in terms of temperature and burn-up for possible
use in advanced pebble bed HTRs with very high coolant outlet temperature (up
to 1000°C) and improved sustainability. A first experiment with 5 German AVR
fuel pebbles (HFR-EU1bis) was completed in 2005 and followed by a second
(HFR-EU1) to be completed in early 2010 which investigates higher burn-up
tolerance of existing German pebbles and of newly produced Chinese fuel. In the HFR-EU1 experiment, the irradiation
targets are 5 pebbles irradiated in 2 separately controlled capsules. Two of
the pebbles were of recent Chinese production (INET), the other three of former
German production (AVR). Both fuel types were tested to higher burn-up but at
lower temperature than in HFR-EU1bis. Contrary to HFR-EU1bis, in this test, the
fuel surface temperatures were kept constant at 900°C (INET) and 950°C
(AVR). These conditions are more benign for the fuel, because increasing
burn-up causes decreasing central fuel temperature with time. The initially
targeted burn-up was 17% FIMA (INET) and 20% FIMA (AVR) which is significantly
higher than the licence limit of the HTR-Modul (approx. 8% FIMA). In the course
of the experiment, this objective had however to be reduced due to excessive
irradiation time requirements and technological difficulties, notably with
premature thermocouple drop-outs. In early 2008, massive thermocouple failure
in the capsule containing AVR pebbles had put the experiment on hold for 1.5
years. The above failure meant that a new safety
case had to be made and to implement and qualify new safety instrumentation
including up-to-date HPGe gamma spectrometry for fission gas release analysis.
This new installation allowed permanent fission gas release monitoring of the
capsules. So far, the measured release over birth values (R/B) remained
consistently low in both capsules, thus hinting at the absence of particle
failure even at the already achieved high burn-ups. The irradiation could eventually be resumed
at the end of 2009 with a foreseen end of irradiation in February 2010, just
before the planned HFR outage. After termination of the experiment, the
irradiation capsule will be dismantled and transported to JRC-ITU (Karlsruhe)
for further PIE and safety testing.
5.
Fuel and Reactor Structural Materials
5.1.
PYCASSO experiments: for Tighter HTR Fuels
Within the
Raphael (V)HTR 6th Framework EU-programme, the PYCASSO experiments have been
devised to investigate coating behaviour under irradiation. Samples have been
included from CEA (France), JAEA (Japan) and KAERI (Republic of Korea), which
makes this irradiation a real Generation IV effort. PYCASSO-I has
been removed after a very successful irradiation in April 2009. The complex
dismantling started in autumn of the same year. During the
autumn of 2009, the PYCASSO-II experiment has been introduced into the HFR
reactor core. Based on the already excellent performance of PYCASSO-I, some
improvements have been introduced, which has resulted in an even more uniform
temperature distribution in the different sections in the experiment. As in
PYCASSO-I, the PYCASSO-II irradiation targets temperature regions of 900, 1000
and 1100°C, and contains 76 separate particle sample holders. For the CEA
particles a larger fluence difference has been envisaged, which has been
achieved by moving one CEA section lower in the experiment, and thus at a lower
flux level in the HFR core. This section is intended to receive a fluence
similar to the maximum fluence in PYCASSO-I, for reference, whilst the other
sections will receive a higher fluence by increasing the irradiation duration. The irradiation
has been somewhat delayed by the HFR repair, and will continue with 2 or 3 more
cycles after the repair, hence ending at the end of 2010.
5.2.
Particle size assessment in ODS Steels using
Small Angle Neutron Scattering
Oxide Dispersion Strengthened (ODS) Steels
are among the candidate materials for use in future generation nuclear power
systems. The structural and fuel cladding materials in GEN IV systems are
confronted with more aggressive environments than in current light water
reactors. This concerns thermal loading, corrosive behaviour of the primary
coolant, neutron dose or their synergetic effect. Small Angle Neutron
Scattering (SANS) is a method for analysing material inhomogeneities in the
1-1000 Å scale. The scattering data furnishes information concerning size and
size distributions of inhomogenities within materials. It can therefore be used
to study effects of thermal and/or irradiation ageing in ODS, duplex or Cr rich
ferritic steels. In 2009, the SANS facility at the HFR has
been used to collect scattering data from coarse grained ODS steels of grades
MA6000, MA956, MA957 and PM2000. The analysis suggests an average size of
embedded oxide nanoparticles of around 28 nm. The calculated mean particle size
is in good agreement with observations made on this material by Transmission
Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM).
5.3.
HTR Core Structures: Graphite Irradiations
Graphite is a suitable material to be used
as a neutron moderator and reflector in nuclear reactors. Due to its excellent
high temperature performance, graphite is used as a structural material in the
HTR design (High Temperature Reactor). The European Commission is supporting
research projects (RAPHAEL-IP) for the development of HTR technology with the
aim to create the technological requirements for designing and constructing an
HTR in Europe. To achieve this, new nuclear graphite grades need to be
developed and qualified, as the previously used grades are not available
anymore. The properties of graphite are changing significantly and non-linearly
under neutron irradiation. Therefore the graphite properties need to be
obtained at different neutron dose levels. The property curves at two
irradiation temperatures, 750ºC and 950ºC, are produced in four irradiation
experiments conducted by NRG at the HFR. A crucial part of the programme is the
possibility to reload irradiated (and therefore radioactive) graphite samples
in new experiments to be able to measure the properties at different dose
levels. This requires being able to build the experiments in a shielded
environment, i.e. a hot-cell. In 2009, the experiments INNOGRAPH 1b and
INNOGRAPH 2b, loaded with irradiated material from the previous experiments,
have been further irradiated. The experiment at 950ºC started in 2008, with
samples previously irradiated up to 7 dpa (displacements per atom). An extra
dose of 6 dpa is targeted, leading to a cumulative dose in these samples of 13
dpa, to be achieved early 2010. The experiment at 750ºC, which started in
2007, is still in the HFR. This experiment will be completed by early 2010,
after achieving an even higher dose of 23 dpa.
5.4.
BLACKSTONE Irradiations: Investigation of AGR
Lifetime Extension
The UK has a fleet of Advanced Gas Cooled
Reactors (AGRs) operated by British Energy. In order to extend the lifetime of
the AGRs, graphite data at high dose and weight loss are required. These data
allow the prediction and assessment of the behaviour of AGR graphite cores
beyond their currently estimated lifetimes. Graphite degradation is indeed
considered to be one of the key issues that will determine the remaining life
of the AGRs. The BLACKSTONE irradiations use samples trepanned from AGR core
graphite and subject them to accelerated degradation in the HFR. The results
are designed to enable the future condition of the AGR graphite to be predicted
with confidence. The BLACKSTONE irradiations started in the
first cycle after the HFR stop due to the BPL problem. The BLACKSTONE capsules
will continue into 2010 to achieve an irradiation dose of approx. 7 dpa.
6.
Fusion Reactor Technology
The HFR irradiation capabilities are used
for screening and qualifying fusion materials, components and technology. The
HFR contributes to fusion technology development by simulating ITER and DEMO
conditions in terms of irradiation temperature and neutron load. Furthermore,
the hot cell laboratories perform post-irradiation testing, subsequently
providing experimental results on neutron irradiated materials. The main areas
of interest are the ITER vacuum vessel, the development of high heat flux
components and blanket structures, and the development of the reduced
activation materials such as 9Cr steels and innovative materials such as fibre
reinforced composites. In addition, irradiation behaviour of ITER diagnostic
instrumentation and the in-vessel parts of heating systems, which require
dedicated assessment and testing programmes, are of great interest. As part of
the qualification of materials supporting the licensing of a future reactor,
the design of the International Fusion Materials Irradiation Facility (IFMIF)
is under development. The HFR provides ample opportunity to qualify specific
materials for the IFMIF target section, instrumentation and mock-ups.
Presentations on ITER and DEMO development and qualification activities and the
role of HFR in these activities have been delivered at the regular Fusion Symposia and Conferences.
6.1.
ITER Vessel/In-vessel
In one of the European
design concepts, the design of ITER first wall panels features PH13-8Mo steel
as candidate material. After an irradiation campaign, the final report on the Post Irradiation Examination (PIE) of PH13-8Mo
has been completed. This report is comprised of the results of the irradiation
response up to 2 dpa in terms of yield stress hardening, elastic fatigue
resistance and fatigue crack propagation. Furthermore, a new test facility, called
POSITIFE, for the irradiation of ITER primary wall modules is under
construction. This facility will allow close simulations of thermal fatigue and
simultaneous neutron loading in the HFR Pool Side Facility (PSF). The
manufacturing of the components for this irradiation experiment started in
2009. The irradiation will start soon after the repair of the HFR in 2010. NRG also developed with
the Netherlands Organization for Applied Scientific
Research (TNO) alternative
manufacturing routes for thick tungsten claddings on copper-base substrates.
Explosive forming of thick stainless steel sections was demonstrated by
Exploform BV, in a joint effort with NRG and TNO to provide alternative manufacturing
solutions for the ITER vacuum vessel. The experimental part of both projects on
the cladding and the vessel were finished in 2008. Both final reports are now
completed. The irradiation response of ODS-Eurofer97
steel at low and medium doses has been investigated by performing irradiation
in the SUMO-11 and SUMO-12 experiments. The PIE of the ODS Eurofer97 has been
completed in 2009. The final report is expected in 2010.
6.2.
HIDOBE Experiments: Beryllium for Fusion
The two objectives of the HIDOBE (HIgh DOse
BEryllium irradiation) project are (i) to quantify the long-term behaviour (in
terms of swelling, creep and tritium retention for fusion applications) of
beryllium under irradiation conditions and (ii) to validate models for the
thermo-mechanical behaviour of beryllium under irradiation conditions and
tritium kinetics in beryllium. Various grades of beryllium (in pebble and
pellet form) and titanium beryllides are irradiated in the HFR for 2 and 4-year
periods, in two separate experimental setups (HIDOBE-01 and 02). In the
framework of the IEA agreement on Radiation Damage Effects in Fusion Materials,
partners in the EU, Japan and the Russian Federation provided these different
grades of beryllium specimens. The experiment contained a few piggy-backs of
ceramic breeder pebbles, complementary to the shielded HICU case. Irradiation of HIDOBE-01 has been completed
in 2008, with achieving its target dose of 3,000 appm helium. The dismantling
has been successfully carried out in 2009 and up to 85% of the samples have
been recovered without problems. Preparations for an extensive PIE campaign
have been finished in 2009 and PIE will begin in 2010. The HIDOBE-02 irradiation will continue in
2010, after repair of the BPL, to accumulate a total dose of 6000 appm helium
production in beryllium and is expected to finish irradiation in the second
quarter of 2011. EXTREMAT: Materials for Extreme
Environment (Fission & Fusion)
6.3.
EXTREMAT : Materials for extreme environment
(Fission and Fusion)
Within various subprojects of the ExtreMat
Integrated Project, a large number of materials were developed for use in
extreme environments. Their stability under neutron load is investigated by
irradiations in the HFR. To this aim, two irradiation capsules have been
designed: A high neutron dose capsule (equivalent neutron dose in stainless
steel of 5 dpa) in which specimens are irradiated at temperatures of 600°C and
900°C and a low neutron dose capsule, designed to reach a neutron dose of 0.7
dpa, at temperatures of 300°C and 550°C. Irradiation of both capsules started in
2008 and finished in 2009. Afterwards, the low dose capsule was dismantled and
the PIE started and will continue into 2010. The PIE includes measurements of
physical properties such as thermal conductivity, thermal expansion and dynamic
Young’s modulus and mechanical properties such as tensile and flexural
strength.
6.4.
ADS Material Development
An experimental Accelerator Driven System
(ADS) for the transmutation of Actinides is under development in Europe. It
features Liquid Lead Bismuth Eutectic (LBE) as reactor coolant. Lead Bismuth
has a low melting point (135 ˚C), but has corrosive properties to
structural materials and welds. In addition, transmutation of Bi to the high
radiotoxic 210Po is a safety issue in the design of the ADS.
Materials R&D is needed to test the corrosion behaviour of T91, 316L and
weld specimens during irradiation in contact with LBE, and to examine the
deposition of 210Po in the irradiation containers and on the
specimens after irradiation. The irradiation of the two capsules was
completed after the first three cycles of 2009. Due to the HFR core loading,
the IBIS experiment was moved from position G7 to H6 for the last cycle. Also
there, the target temperatures of 300 and 500oC were achieved. IBIS
has been irradiated in the HFR for 250 Full Power Days in total, to an
irradiation dose ranging from 1 (lower temperature) to 2 dpa (high temperature
capsule). During 2009, the facility for specimen
retrieval was commissioned and built in the Hot Cell Laboratory. The Fuel Cell
line of the HCL was selected because of the presence of alpha emitting
radionuclide 210Po. To assess the risk on handling 210Po,
a HAZOP study was performed, which formed the basis of the workplan for the
retrieval of specimens. The procedure on the retrieval was performed on a
container loaded with specimens and LBE that was not irradiated. Almost no
wetting of the LBE on the specimens was observed. A dedicated tensile machine
was also installed in this cell to test the irradiated specimens. The tensile
specimens have showed no effects of the cyclic heating to 300oC in
LBE on the elongation and the ultimate tensile strength.
7.
Isotope Production
The year 2009 was again a year of high
contrast. It started with the HFR being first out of operation, then operated
only when justified by medical necessity and finally operated during the second
half of 2009 at absolute maximum medical isotope production capacity. The HFR entered into operation in
mid-February 2009, when it was allowed to operate, only upon request, for
medical isotopes production. This was imposed by the lack of alternative supply
options in Europe and elsewhere in the world. This process required that each
operating cycle was individually justified and approved by the Dutch
Government, leading to a series of discontinuous cycles of different
operational length. These variations in operation reflect the non-availability
of other reactors in the European supply network. Over this period, the HFR ran
at relatively high medical isotope production levels, to palliate limited
alternative supply options. In mid-May 2009, the NRU Reactor in Canada (a
medical isotope producer) unexpectedly went out of operation due to the
identification of a heavy water leak. It remained out of operation for the rest
of 2009, triggering a continuous worldwide medical isotope shortage. The
response of NRG was to reconfigure the production facilities and operating
priorities of the HFR to allow the absolute maximum production levels of key
medical isotopes (in particular the production of Molybdenum-99 for Tc-99m
Generators). These changes were successfully implemented within 2 weeks after
the notification of the NRU problem and Mo-99 production capacity was increased
to a level around 180% of normal production. The reconfiguration allowed as
many as 11 Mo-99 production irradiations to be performed in parallel. It was
estimated that during this period the HFR produced enough material to allow
more than 50,000 patient scans per day to be performed worldwide. This
represented around 60% of the normal total world demand. The extreme focus on medical isotope
production was extended to all other medical isotopes which were produced in
large quantities. This had unfortunately negative effects upon industrial isotope
production and in particular on the newly developed business of the irradiation
of Silicon Ingots to produce Neutron Transmutation Doped (NTP) Silicon for use
in high voltage and other specialist electronic applications. Production of NTP
Silicon was suspended until further notice, but it is anticipated that
irradiations for this market will be reintroduced during the course of 2010. During the year, NRG worked closely with
other reactors in the medical isotope supply network, the Radiopharmaceutical
Companies, the Medical Community, Governmental Departments and international
organizations such as the OECD/NEA and the IAEA. These actions aimed at
maximizing coordination and cooperation and as a result minimizing the effects
of shortages whenever possible. Once again, the year 2009 fully underlined the
critical role performed by the HFR and the supporting infrastructure within NRG
to ensure the worldwide continuous and smooth supply of isotopes for essential
medical services.
8.
Financial contributions for the execution of the
programme.
In 2009, the following financial
contributions were received from Member States for the execution of the
programme: - Belgium: 400,000 € - France: 300,000 € - The Netherlands: 8,223,000 € It should be noted that these contributions
cover the expenses according to Annex II to Council Decision 2009/410/Euratom. These
amounts have been calculated in order to balance the forecasted costs of the
reactor on the period 2009 taking into account an expected level of commercial
incomes. In no case does the Commission cover any operational deficit,
including potential costs for maintenance or repair. From this amount the Commission received
800,000 € as provisions for the Decommissioning fund[1] Other expenditures incurred by JRC and paid
from the supplementary programme budget: - Direct Personnel (e.g. for HFR Supplementary
program Management): 276,000 € - Support HFR (e.g. Legal Advice): 24,000 € - Utilities (e.g., electricity, water,
heating): 783,000 € - Spent Fuel Management: 1,741,000 € Due to an unplanned investigation and
inspection period in the beginning of the year (period 1/1/2009 to11/2/2009 –
see Table 1), the net result for NRG for the operation of the HFR in 2009 was a
deficit of 1,090,000 €. Glossary and Acronyms ADS Accelerator
Driven Systems appm atomic
parts per million CEA Commissariat
à l’Energie Atomique COVRA Centrale
Organisatie Voor Radioactief Afval DEMO Demonstration
Fusion Reactor DG Directorate
General dpa displacements
per atom EC European
Commission ECN Energieonderzoek
Centrum Nederland EU European
Union EUROTRANS European
Transmutation FAIRFUELS Fabrication,
Irradiation and Reprocessing of FUELS and target for transmutation FIMA Fission
per Initial Metal Atoms FP or FWP Framework
programme GIF Generation
IV International Forum HABOG Interim
storage centre for high level waste HAZOP Hazard
and Operability HB Horizontal
Beam Tube HCL Hot
Cell Laboratories HELIOS Helium
in Oxide Structure HEU High
Enriched Uranium HFR High
Flux Reactor HICU High-fluence
Irradiation of breeder Ceramics HIDOBE High
Dose Beryllium Irradiation Rig HTR High
Temperature Reactor IAEA International
Atomic Energy Agency IE JRC
Institute for Energy, Petten (NL) IEA International
Energy Agency ITER International
Thermonuclear Experimental Reactor JAEA Japan
Atomic Energy Agent JRC Joint
Research Centre KAERI Korea
Atomic Energy Research Institute KFD Kernfysische Dienst
LBE Lead
Bismuth Eutectic LEU Low
Enriched Uranium MARIOS Minor
Actinides in Sodium-cooled Fast Reactors NET Network
on Neutron Techniques Standardisation for Structural Integrity NRG Nuclear
Research and consultancy Group PBA Pebble
Bed Assemblies PBMR Pebble
Bed Modular Reactor POSITIFE Project
Pool Side facility Thermally Induced Fatigue PYCASSO PYcarbon
irradiation Creep and Swelling/Shrinking of Objects PSF Pool
Side Facility R&D Research
and Development RAPHAEL Reactor
for Process Heat and Electricity RTD Research
and Technological Development SANS Small
Angle Neutron Scattering SUMO In-Sodium
Steel Mixed Specimens Irradiation TG Task
Group TN Technology
Network TNO Nederlandse
Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek (Netherlands
Organization for Applied Scientific Research) [1] The yearly contribution to
the decommissioning fund has passed from 400,000 €/year to 800,000 €/year since
2004 due to a re-evaluation of decommissioning costs. This amount is taken from
both the regular budget of the
supplementary programme and by the gained interest on the bank account of the supplementary
programme (the amount of the interest over 2009 was € 374K and therefore, €426K
was added from the regular supplementary
programme budget of
2009).