The Brazilian nuclear sector on 30 August took an important step towards expanding its uranium enrichment capacity with the aim of becoming self-sufficient in the supply of nuclear fuel for its nuclear power plants.
The seventh cascade of ultracentrifuges was inaugurated at Indústrias Nucleares do Brasil’s (INB’s) Nuclear Fuel Factory (FCN) in Resende, increasing the production of enriched uranium by 25% and enabling INB to supply about 50% of what is necessary to refuel of unit 1 of the Angra NPP in Angra dos Reis. “We are increasingly consolidating ourselves as a technological reference in the nuclear sector on a global scale," said INB president Reinaldo Gonzaga. Minister of Science, Technology, Innovation and Communications Gilberto Kassab, noted the role of INB in supporting institutes and entities linked to the Ministry and its importance to Brazilian science. "INB is fundamental for the Brazilian nuclear sector; its activity is very important for the country,” he said.
The inauguration was part of the first development phase of the Uranium Isotopic Enrichment Plant, a joint project with the Brazilian Navy, which aims to install tem cascades of ultracentrifuges, and will eventually meet around 70% of the demand for enriched uranium required by Angra 1. The second phase will see the installation and commissioning of 30 more cascades, which will give INB the capacity to fully meet the fuel needs of Angra 1, 2 and 3, and will achieve commercial scale production. Since 2000, BRL560 million ($138m) has already been invested in the project, and by 2033 the total cost is expected to reach BRL3 billion.
Brazil's two operating nuclear reactors, Angra 1&2, generate about 3% of its electricity, and a third unit is under construction.
Brazil has significant uranium resources and is ranked sixth in the world with only a third of the country adequately explored. Over the past few decades it has mastered the entire fuel cycle from mining through to waste disposal using a combination of indigenous and transferred technologies and by pursuing two parallel development programmes. However, not all stages of the fuel cycle have been developed to the industrial stage, and some conversion and enrichment services are still purchased from abroad.
Uranium needed to fuel Brazil's power reactors previously was supplied as uranium concentrate to Cameco in Canada to be converted into uranium hexafluoride (UF6) gas, which was then sent to Urenco's enrichment plants in Europe. After enrichment, the gas was returned to Brazil for INB to reconvert the UF6 gas to powder, which it then fills into nuclear fuel pellets at Resende.
INB has five operational units and two projects:
- FCN (Fabrica de Combustivel Nuclear at Resende in Rio de Janeiro state - a nuclear fuel factory;
- URA (Unidade de Concentrado de Uranio) at Caetite in Bahia state - a uranium treatment facility at Caetite, site of the new Lagoa Real uranium mine;
- UTM (Unidade de Tratamento de Minerios) at Pocos de Caldas in Minas Gerais state - a closed facility for processing monazite (USAM - Usina de Santo Amaro) and the site of a closed uranium mine;
- UMP (Unidade de Minerais Pesados) at Buena in Rio de Janeiro State - a demonstration plant for solvent extraction of individual rare earth oxides; INB is seeking association with the private sector to build an industrial facility;
- INB Sao Paulo - decommissioning facilities of former Nuclemon in Sao Paulo;
- Project Itataia in Ceara state (Unidade de Concentrada de Santa Quiteria) - development of uranium extraction combined with phosphate mining;
- Project Gandarela in Minas Gerais state - geological research.
Brazil’s conversion capabilities are being developed as part of Brazilian Navy’s nuclear propulsion programme, and a UF6 pilot plant is under construction at the Aramar research complex at Ipero (São Paulo) - Usina de Gas de Uranio (Usexa) The plant is planned to have a nominal production capacity of 40t/yr and is intended primarily to provide fuel for Brazil’s planned nuclear submarine which is scheduled to begin operating in 2020. André Luis Ferreira Marques, the coordinator of the Navy's Nuclear Propulsion Programme, told Agência Brasil that Usexa is now nearing commissioning. Meanwhile, INB has developed the technology for the reconversion of UF6 to uranium dioxide (UO2) for pellet manufacture, which takes place at Resende.
Enrichment: a history
Brazil’s efforts to master enrichment began in 1979 under a Naval programme code-named Project Cyclone led by Othon Luiz Pinheiro da Silva. It started with seven engineers working at the Institute for Energy & Nuclear Research (Instituto de Pesquisas Energeticas e Nucleares - IPEN) on the campus of the University of Sao Paulo with limited funding and facilities. Using a single centrifuge, the team performed their first successful enrichment experiment in 1982.
In 1987 the researchers at the Navy’s Isotopic Enrichment Laboratory (Laboratorio Enriquecim Isotopico - LEI) at the Aramar Centre in Ipero assembled a small module of 48 centrifuges and reportedly produced several kilograms of uranium enriched to 1.2%. In 1988 the Navy opened a pilot ultracentrifuge enrichment facility there (Usina Enriquecim Piloto - Uside). It was intended to enrich uranium to no more than 5% for research and submarine reactors, but in 1989 Brazil announced that small amounts of uranium enriched to 20% had been produced. The plant was expanded to about 500 centrifuges by 1991. Brazil developed its own centrifuges for enrichment. Work on the centrifuges took place at the Navy Technology Centre in Sao Paulo, while manufacturing took place at the Aramar Centre.
The Navy continues to operate the research and pilot facilities related to its enrichment programme at its experimental centre in Aramar providing services and products for Brazil’s power reactors and research reactors. In 2000, the Navy was commissioned to construct a commercial centrifuge enrichment facility for INB using this technology. The Brazilian government reportedly agreed to pay $130 million to fund the project. After several years delay, INB inaugurated the first of four planned modules at its Resende facility in May 2006.
This is the first of four planned modules totalling 115,000 SWU a year. Each module consists of four or five cascades of 5000-6000 SWU a year. In 2009, it was announced that INB would begin full operation of the Resende plant that year. The Phase 1 plant was initially expected to produce 60% of the fuel needs of Angra units 1&2 by 2012. Stage 2 will take capacity to 200,000 SWU. The centrifuges are domestically developed and very similar to Urenco technology. INB's fuel fabrication plant, designed by Siemens, is also at Resende, with a capacity of 160 tonnes a year of pellet production and 280 tonnes a year of fuel assembly production.