Five plants convert the world's uranium, and one of them was switched off for six years
Between the uranium mine and the enrichment plant sits a step almost nobody writes about, performed at five industrial sites on earth.
Conversion turns uranium oxide concentrate into uranium hexafluoride. The reason is simple physics: enrichment separates isotopes by mass in a spinning centrifuge, and that requires a gas. Uranium metal boils above 4,000 °C. Uranium hexafluoride sublimes at 56 °C. UF6 is the only compound of uranium that is conveniently gaseous, so the entire enrichment industry is built on it.
The five
- Cameco, Port Hope, Canada — 12,500 tU/yr
- Orano, Malvési and Tricastin, France — 15,000 tU/yr
- ConverDyn, Metropolis, USA — 7,000 tU/yr
- Rosatom, Seversk, Russia — 12,500 tU/yr
- CNNC, Lanzhou and Hengyang, China — 15,000 tU/yr
About 62,000 tU/yr of world capacity, against 2022 production of roughly 42,000 tU.
The six-year gap
Conversion was a miserable business for most of the 2010s. Margins were thin, the plants are chemical plants with the safety case of chemical plants, and UF6 reacts violently with water including atmospheric moisture.
In 2017, Honeywell idled Metropolis Works — the only uranium conversion plant in the United States — because the price no longer covered the cost of running it. For six years, a country with 94 operating reactors converted no uranium at all. It restarted in 2023, after the invasion of Ukraine tightened the market.
That episode is the argument for paying attention to this stage. Mining responds to price within a year or two; idled mines reopen. Conversion does not. Restarting Metropolis took roughly two years, and building a new plant takes far longer than that.
Why it constrains countries, not just companies
A country without conversion cannot use its own uranium, however much it mines. Australia holds the world’s largest known uranium resources and has no conversion capacity, no enrichment, and a federal prohibition on nuclear power generation. It ships yellowcake abroad and buys nothing back.
Kazakhstan, which supplies 39% of world uranium, has no commercial conversion either. It has moved one step downstream into fabrication at Ust-Kamenogorsk, but the middle of its own chain runs through other countries.
See the conversion stage page for each plant.