International expert in uranium processing

After the natural uranium ore extraction process, conversion is a key step in providing nuclear power plants with fuel adapted to the needs of nuclear reactors. With an integrated industrial platform unparalleled worldwide, Orano Group is one of the global leaders in uranium conversion and enrichment activities.
Em3 workshop test before production, site of Tricastin, France Em3 workshop test before production, site of Tricastin, France © Eric Larrayadieu / Orano

Orano, a major international player in uranium conversion

An expert in uranium transformation, purification, enrichment & fluorine chemistry

On the road to Nuclear Plants 4.0
facilities setting the international standard: Orano la Hague, Orano Melox
No. 3
worldwide in Enrichment
No. 1
Western No.1 in Conversion
of operations in export
clients and 40 partners world-wide (France, Europe, Asia and the Americas)
Nearly €1 Bn in revenues (nearly 1/4 of Orano's revenues)
+ 10
Over 10 years of revenue in order backlog
years of industrial experience in conversion, chemistry and enrichment

Safe, reliable and competitive operations

  • A successful industrial transition
  • €5 Bn invested since 2006 to upgrade the industrial facilities
  • Investments maintained at €1 M/yr in average for the next 10 years.
    • Plans to create new infrastructures
    • Facility renovations
  • An industrial platform that looks to the future

A uranium conversion plan like none other worldwide

Industrial facilities recognized all over the world

The conversion and enrichment operations are carried out across two sites, in Malvési and Tricastin. Underpinned by this unique integrated industrial platform and thanks to its upgraded facilities - Comurhex II for conversion and Georges Besse II for enrichment - Orano offers its customers the most modern infrastructures in the world, recognized across the market for its technical skills and state-of-the-art processes.

High added-value processing operations serving its clients

The only industrial players capable of receiving concentrates in all forms, with an industrial platform that also offers warehousing capacity in compliance with all authorizations held. It makes it possible to deploy custom-tailored services in accordance with customer needs: conversion, defluorination and denitration.

Production capacity suited to current developments

With its Comurhex II plants for conversion and the Georges Besse II plants for enrichment, the two major transformation activities have entered a new era. The modularity of Georges Besse II gives these two plants the potential to evolve according to market demand and needs.

Securing long-term supply for its customers

Thanks to its safe, reliable and competitive European presence, Orano is able to secure supply for its customers' and the sustainability of its operations for the next 40 years.

  • Front-End Solutions to Your Business Needs – Uranium Mining, Chemistry, Enrichment

Comurhex II

Comurhex II © Orano

Cutting-edge technologies serving top performance

Uranium conversion as a strategic step for reaching “nuclear purity”

An essential stage, in the upstream fuel cycle, between the recovery of natural uranium from mines and the enrichment phase, conversion consists of purifying and transforming uranium ore. These conversion and enrichment activities precede the final stage of fuel fabrication for nuclear power plant reactors.

Conversion is carried out in two stages, at two complementary sites:
Conversion plant of UF4 to UF6 Comurhex II Pierrelatte. Site of Tricastin (France) Conversion plant of UF4 to UF6 Comurhex II Pierrelatte. Site of Tricastin (France) © LARRAYADIEU ERIC
Uranium purification

1) Purifying: the ability to process any type of uranium ore

  • The Malvési (Aude) site purifies uranium concentrates from mines around the world and converts them into uranium tetrafluoride (UF4).
  • The site provides thermal denitration services using an innovative and unique process worldwide, Isoflash (UO3), which eliminates chemical product input, in particular ammonia.
  • Hydrofluorination then consists of adding 4 fluorine atoms to a natural uranium atom to obtain uranium tetrafluoride (UF4)

Orano, a key player in uranium ore purification

Unparalleled : thanks to the superior performance of the facilities in Orano Malvési, the degree of purification is such that the process can address all forms of uranium ore, whatever its origin or degree of impurity.

2) Conversion into UF6 (Orano Tricastin)

Specialized in fluorine and uranium chemistry in all forms, the Tricastin site (Drôme), with 55 years of know-how, has become a reference industrial platform. Its activities include completing the transformation of UF4 into uranium hexafluoride (UF6), by adding 2 additional fluorine atoms before enrichment.

Refurbished plants

These past few years, Orano Malvési and Orano Tricastin have undergone considerable change, to renew their industrial equipment and improve the safety and competitiveness of the sites and the sector.

Comurhex II, heightened safety, in line with the latest standards

Launched in 2006, the Comurhex II program consisted of renewing three  facilities at the Malvési site and building a new plant on the Tricastin site to replace Comurhex 1. The SEVESO High Threshold (ICPE) facility built to nuclear standards allows reinforced containment of the material: protected concrete buildings with autonomous ventilation, compartmentalization of the main building into 200 rooms, increased resistance safe shutdown earthquakes, and flood risk prevention.

Uranium enrichment: technologies enabling premium performance

From natural uranium to combustible uranium
To be usable as fuel in reactors, uranium must have a concentration of 2 to 5% uranium 235. Since natural uranium contains only 0.7%, enrichment operations will increase its concentration.

Separating uranium 235 and uranium 238 by centrifugation
Under the effect of centrifugal force, molecules are separated. This isotopic separation step is repeated in series. After these operations in cascade, the enriched UF6 is extracted directly into a suitable cylinder before solidifying in a dedicated station. The depleted UF6 is extracted into another cylinder which is also cooled.

Quality control of enriched UF6
The production of enriched UF6 is sampled then conditioned in cylinders to be shipped to the fuel manufacturer.

A high-performance technology with a smaller environmental footprint

Ensuring UF₆ quality: it is Moana and his team’s mission

ItsMyJob: Moana Mauru, head of UF₆ analysis laboratory at the Tricastin site © So On Pictures

Georges Besse II, a yield rate exceeding 99 %


After 50 years of experience in enrichment based on gaseous diffusion, enrichment continues at the Tricastin site, in the two new "Georges Besse II" plants using ultra-centrifugation technology.

The largest enrichment plant in Europe, Georges Besse II replaces the Eurodif plant, which for over 30 years produced uranium enriched via gaseous diffusion.

Commissioned in 2011, the plant reached its full capacity in end-2016. The first tests carried out confirm the facilities’ high performance levels, with yield rates in excess of 99%.

Its design enables operation according to the highest safety and security standards, in particular earthquake resistance, fire fighting and material containment.


Recognized for its know-how in uranium reconditioning

Two different chemical processes are used to recover depleted uranium into uranium oxide (U3O8), in safe and easily storable forms.

  • Defluorination processing uranium for safe storage before reuse
    Uranium enrichment generates UF6 depleted in recoverable isotope 235. It is then sent to the Tricastin defluorination plant, to be transformed into uranium oxide U3O8. U3O8, insoluble and stable material, can be safely stored before further recycling.
W plant, defluorination of the depleted uranium. Orano, Tricastin site. France W plant, defluorination of the depleted uranium. Tricastin site. France © Larrayadieu Eric
  • Denitration, recycling uranium from spent fuel processing
    After 4 years in a reactor, the fuel still contains 95% uranium.After processing at the La Hague plant, uranium is conditioned into uranyl nitrate and transported to the Tricastin site. The uranyl nitrate is denitrated for reconditioning as uranium oxide for safe and stable storage prior to subsequent reuse.
Denitration, recycling uranium from spent fuel processing - Orano, Tricastin site. France Denitration, recycling uranium from spent fuel processing - Tricastin site. France © Orano

An innovative and eco-responsible site

An efficient industrial tool, a reduced environmental footprint

Orano is the first manufacturer in the world to have fully refurbished its conversion plants to step up operational safety and reduce its environmental footprint. The new industrial facilities at the Malvési and Tricastin sites thus have innovative processes and use new technologies that enable it to minimize in its environmental footprint.

  • A 75% reduction ammonia consumption and a 60% reduction in potash thanks to the thermal denitration process.
  • Removal from the natural environment 10 times lower through the implementation of a cooling circuit for the thermal installations.
  • Water consumption now 10 times lower.
  • Greenhouse gas emissions cut by 80%, thanks to conversion and enrichment activities’ being combined on a single site, thus limiting CO2 transport and emissions.
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