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					                           Nuclear Fuel Cycle
                       and Materials Technologies
Objective                                                            nium demand of 66 500 tonnes. The uranium market
                                                                     remains uncertain in the medium term due to con-
To strengthen the capabilities of interested Member States for       tinuing limited information on available secondary
policy making, strategic planning, technology development            supplies and on new uranium production centres. In
and implementation of safe, reliable, economically efficient,          the second half of the year the spot price for uranium
proliferation resistant, environmentally sound and secure            dropped from the peak it reached in June of $135 per
nuclear fuel cycle programmes.                                       lb U3O8 ($351 per kg U) and became more stable at
                                                                     around $90 per lb U3O8 ($234 per kg U). Exploration
                                                                     activities continued to increase worldwide, stimu-
Uranium Production Cycle and the                                     lated by the strong price increase.
Environment                                                             The increasing interest in uranium produc-
                                                                     tion pushed up demand for skilled labour and
    Analysis and exchange of information on ura-                     for information exchange, and produced a large
nium resources, production and demand in Member                      increase in related technical cooperation proposals
States are essential for the steady supply of uranium                to the Agency for implementation in 2009–2011. In
fuel for nuclear power plants in operation and under                 2007, these proposals were reviewed and ten were
construction. Information as of 1 January 2007 shows                 selected for implementation in Africa, Latin America
an increase of 15% over                                                                            and Asia. Also in 2007,
2004 levels in identi-                                                                             the Agency organized
                                         “The increasing interest in uranium production
fied uranium resources                                                                              two training meetings
                                           pushed up demand for skilled labour and for
(i.e. those resources                                                                              in Vienna covering spe-
                                                    information exchange,...”
with production costs                                                                              cial mining and milling
of less than $130 per kg                                                                           technologies and recent
U) to 5.5 million tonnes, which is sufficient, at the                  developments in uranium exploration. A third train-
2006 consumption rate, for almost 100 years. Total                   ing meeting was held in Swakopmund, Namibia,
world production remained at a similar level to                      at which issues related to the uranium production
that reported last year (around 40 000 tonnes; Fig.                  cycle, for example mining technology and envi-
1) and accounted for some 60% of the annual ura-                     ronmental control, were discussed for the benefit



                                   8%                                             Canada
                         5%
                                                               25%
                                                                                  Australia
                    6%
                                                                                  Kazakhstan

                                                                                  Niger
               8%
                                                                                  Russian Federation

                                                                                  Namibia
                 8%
                                                                                  Uzbekistan
                                                                   19%

                                                                                  USA
                         9%

                                          13%                                     Others

                           FIG. 1. Uranium production by country in 2006 (total 39 600 t U).



Technology                                                                                                            21
              FIG. 2. Participants at a technical meeting in Halden examining fuel rod instrumentation.



of African Member States. Through the technical               operating nuclear power reactors. The management
cooperation programme, the Agency also provided               of this spent fuel is an important factor influencing
China and Egypt with advice on methods for ura-               the future of nuclear energy, and deals with issues
nium exploration.                                             related to long term interim storage and spent fuel
                                                              treatment. Less than 20% is currently reprocessed,
Nuclear Power Reactor Fuel                                    and no final repositories are scheduled to open
Engineering                                                   much before 2020 — and then only in a very few
                                                              countries. As the amount of spent fuel in storage
   Several Agency activities during the year                  climbs steadily, so does the need for efficient
addressed fuel performance. A technical meeting               management of all issues related to the long term
held in Halden, Norway, in September considered               interim storage of spent fuel. Five Agency reports
techniques for fuel research and highlighted the              issued in 2007 provide insights and advice on such
methods and instrumentation used to obtain fuel               storage issues.
performance data during reactor operation (Fig. 2).              ‘Burnup credit’ refers to a refinement of the
Such data were used in a CRP on fuel modelling                traditional assumption in criticality safety analyses
at extended burnup (FUMEX-II), which was                      that spent fuel has the same reactivity as fresh fuel.
completed in 2007. The results show that modern               Spent fuel in fact has less reactivity, depending on
fuel performance codes generally perform well at              its burnup. Taking burnup into account reduces
burnups up to around 70 GW·d/t U, and there are               unnecessary over-design. The reports published
satisfactory predictions of fission gas release from           in 2007 present methods for incorporating burnup
most codes.                                                   credit in analyses, identify areas where international
   Initial results in 2007 from a CRP on fuel and             cooperation would be especially valuable in
water chemistry (FUWAC) have clarified the causes              improving methods and make the case for
and conditions for crud formation on fuel in WWER             developing international guidelines.
and LWR systems, and of boron deposition in such                 The reports also present methods for choosing, in
crud. This will help operators be er manage water             any given situation, the best long term and near term
chemistry in their reactors, since changes in water           strategies, the best casks for storage and transport,
chemistry influence both fuel oxidation rates and              the best storage options and the best approach to
the migration of corrosion products from steam                contract management. They also present design
generators to the fuel, where they can accumulate             approaches to improve cask performance while
and lead to fuel failures.                                    recognizing that different designs are needed in
                                                              different situations. They emphasize the increasing
Spent Fuel Management                                         value of fuel data so that fuel can be managed most
                                                              efficiently at all steps of its life cycle, for example
   Annually, some 10 500 tonnes of heavy metal in             through zoned cask loading where cooler spent fuel
the form of spent nuclear fuel is discharged from             is positioned to shield ho er fuel.


22                                                                                              Annual Report 2007
Topical Advanced Nuclear Fuel Cycle                             in Pe en, the Netherlands. The course trained
Issues                                                          graduate students and young researchers in fuel
                                                                design, fabrication, characterization techniques,
    In 2007, activities covered the fuel and fuel cycle         irradiation and post-irradiation examination, and
issues of fast reactors and high temperature gas                waste processing and storage, for coated particle fuel
cooled reactors (HTGRs), partitioning and transmu-              used in high temperature reactors.
tation, burning plutonium and minor actinides in                    Member State interest in using thorium based
fast reactors, reuse options of reprocessed uranium,            fuels is increasing, and a technical meeting on
thorium utilization and                                                                       thorium     fuel  cycle
issues related to pro-                                                                        options for PHWRs,
                                 “Member State interest in using thorium based fuels
liferation resistance in                                                                      LWRs     and     HTGRs
                                                   is increasing, ...”
the nuclear fuel cycle.                                                                       was held in October at
Assistance was provided                                                                       the Çekmece Nuclear
on fuel cycle issues through the Agency’s Interna-              Research and Training Centre, Istanbul. Information
tional Project on Innovative Nuclear Reactors and               was exchanged on thorium availability, processing
Fuel Cycles.                                                    thorium ores, manufacturing, and proliferation
    Technical reports were compiled in cooperation              resistance issues of the thorium fuel cycle.
with experts from Member States in the areas of
fast reactor fuel technology, the back end of the               Integrated Nuclear Fuel Cycle
fast reactor fuel cycle and the current status of and           Information System
future trends in minor actinides. The reports cover
state of the art information on plutonium and                       Interest in the Agency’s databases and simulation
minor actinide bearing oxide, carbide, nitride and             systems in the area of the nuclear fuel cycle
metallic fuels for fast reactors, their fabrication,           continues to increase. Registered users increased
properties and irradiation behaviour and aqueous               in 2007 by some 25%. The databases that provide
and pyroelecrolytic routes for partitioning of spent           information on worldwide nuclear fuel cycle
fast reactor fuels. The reuse options of the increasing        activities include the Nuclear Fuel Cycle Information
quantities of reprocessed uranium were summarized              Systems, World Distribution of Uranium Deposits,
in Management of Reprocessed Uranium: Current Status           Post-irradiation Examination Facilities Database,
and Future Trends (IAEA-TECDOC-1529), which was                Minor Actinide Property Database and Nuclear
published in February.                                         Fuel Cycle Simulation System (formerly known
    In the area of HTGR research, the Agency, in               as VISTA). A web based application has been
collaboration with the European Commission                     developed for using NFCSS through the Internet.
and the ReActor for Process heat, Hydrogen                     All databases and NFCSS applications are available
And ELectricity generation (RAPHAEL) group,                    at h p://www-nfcis.iaea.org/.
conducted a course in December on coated particles




Technology                                                                                                       23

				
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