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BUSINESS OVERVIEW
06
6.4 Operations
At the same time, the PRISME program, designed to reduce the remaining
radioactivity in Eurodif’s gaseous diffusion enrichment plant in preparation for its
dismantling, continues according to the projected schedule and will be completed
at the end of 2016. The most critical phase, consisting of removing the majority of
the uranium present, was completed in October 2015. At the same time, AREVA
filed the application for a dismantling permit at the end of March 2015. Submittals
are still beingmade, with the public hearing scheduled to start inmid-January 2017.
CENTRIFUGATION CONCEPT
Enriched
uranium
Feed
Depleted
uranium
238
U F
6
235
U F
6
Source:AREVA.
The centrifugation process takes advantage of the difference in the atomic weight
of
235
U and
238
U to separate those two isotopes in the UF
6
.
The centrifugal force concentrates the heaviest particles at the cylinder walls,
creating isotopic separation. The gas enriched in the lighter isotope, located closer
to the center of the bowl, flows towards the top of the machine, while the gas with
the heavier isotope flows towards the bottom. The enriched and depleted products
are recovered at either end of the machine.
Conversion of depleted uranium hexafluoride (depleted UF
6
)
into an oxide
Uranium enrichment generates uranium hexafluoride (UF
6
) depleted in the
uranium-235 isotope. This depleted uranium is converted into a stable, insoluble,
non-corrosive uranium oxide which can be safely stored pending reuse, either in
its depleted state or after a new enrichment stage. Very few defluorination facilities
in the world are able to convert depleted uranium hexafluoride into an oxide on a
production scale.
The conversion of depleted uranium hexafluoride into an oxide generates a
byproduct: an ultra-pure, aqueous, 70% hydrofluoric acid, which is marketed.
AREVA earns a return from its internationally recognized expertise in depleted
uranium defluorination through technology sales agreements with world-class
companies. AREVA’s know-how enables customers to store this reusable material
safely and to produce hydrofluoric acid that can be marketed to the chemical
industry. AREVA’s know-how led to the signature of contracts with Tenex and Urenco
for the sale and installation of defluorination lines.
Recycling of uranium from used fuel treatment
After a reactor residence time of nearly four years, uranium still represents
approximately 95% of the used nuclear fuel’s content. The uranium is recovered
through treatment operations performed at the AREVA la Hague plant (see
Section 6.4.4.1.
Recycling
) and is shipped in the form of liquid uranyl nitrate for
chemical conversion into a stable oxide powder. Uranium from used fuel treatment
(reprocessed uranium, or RepU) may then be reconverted into uraniumhexafluoride
and re-enriched for reuse in the fabrication of new fuel, in which case it is called
enriched recycled uranium (ERU).
Other fluorine derivatives
The know-howneeded for conversion, particularly in the field of uraniumfluorination,
has served to develop fluorination operations such as the production of chlorine
trifluoride, used to clean enrichment barriers from the Eurodif plant, which was shut
down permanently in 2012.
Human and industrial resources
The operations in the Front End of the fuel cycle (Chemistry and Enrichment) are
split between two industrial sites in France, the Malvési site and the integrated
Tricastin platform:
p
UF
4
is produced by the plant at the AREVA NC Malvési site (annual capacity:
approximately 14,000 metric tons);
p
UF
6
is produced by the plant at the AREVA NC Tricastin site (annual capacity:
approximately 14,000 metric tons);
p
UF
6
is enriched by the Georges Besse II plant of Société d’Enrichissement du
Tricastin (SET) at the Tricastin site (annual capacity: 7.5 million SWU);
p
depleted uranium is defluorinated in the W Plant at the Tricastin site (annual
capacity: approximately 13,000 metric tons);
p
uranyl nitrate is converted into oxide in the TU5 facility at the Tricastin site (annual
capacity: approximately 1,250 metric tons);
p
the integrated Tricastin platform also pools all of the resources for logistics,
laboratory, waste and effluent treatment, and equipment repair in the Department
of Industrial Services, serving all of the site’s plants more efficiently and in a more
cost-effective manner.
On the financial level, SET is wholly owned by SET Holding. The majority of SET
Holding is owned by AREVA NC (subsidiary of New AREVA Holding); two partners
also hold an interest totaling 5% of the capital, i.e. 2.5% for Korea Hydro & Nuclear
Co. Ltd (KHNP) and 2.5% for Japan France Enrichment Investing (JFEI).
AREVA holds a 50% interest in the Enrichment Technology Company (ETC)
alongside Urenco. ETCmanufactures the centrifuges used for uraniumenrichment.
Relations with customers and suppliers
Customers
In 2016, AREVA made deliveries to more than 35 customers across the globe,
mostly in Europe, Asia and the United States. The number and volume of
transactions remained stable in relation to 2015, but the transaction volume was
distinctly lower than pre-Fukushima volumes, in view of the already high level of
coverage of utility requirements.
The enrichment market is structured aroundmulti-year commitments. The backlog
for enrichment operations represents more than 40 utility customers, primarily in
the United States, Europe and Asia, corresponding to the supply of an average of
about 60 reactors worldwide each year.
2016 AREVA
REFERENCE DOCUMENT
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