U.S. nuclear fuel cycle

 U.S. nuclear fuel cycle

Currently in  U.S. almost all the uranium used in U.S. commercial reactors is imported with about half of it coming from Russian weapon grade down blended to low enriched uranium Russia . U.S. domestic mining accounts for only  5 percent of the fuel used in U.S. reactors.

Between 1977 and 2005, government policy did not allow reprocessing of used fuel for commercial reactors. Recent legislation however  calls for stepped up for R& D in advanced fuel technology and advanced reactors to recover the energy value used fuel to reduce the volume of nuclear waste.

In 195o s, the U.S.A had great deal of uranium mining prompted by federal subsidies. Peak production since 1970 was 16,800 t u  in 1980, when there were 250 mines in operation. This abruptly dropped to 54 in 1984, when 5,700 t u  produced and then there was steady decline in 2003, by which time there were only  two small operation producing a total of under 1000 tons u / year or about 5 per cent of uranium consumed by U.S. nuclear power plants. So far the first step in nuclear fuel cycle the U.S. must rely on imports of uranium from countries such as Canada and Australia or down blended weapon grade uranium from Russia .

As the price of uranium increased in recent years, a large number of companies have announced plan to refurbish and restart mines in Wyoming , Colorado , Utah ,Arizona and new Mexico . There are now operating mines in Texas, Wyoming , Colorado  and southern Utah  and Wyoming. Most U.S. production has been from new Mexico and Wyoming ,known resources are 1,67,000 t U3O8 in Wyoming , as 1,55,000 t in New Mexico, 2000 t in Texas and around 50,000 t in Utah, Colorado and Arizona . Production potential is about 45 percent in Situ leach (ISL) 55 percent conventional mining . Uranium production from one mill ( white Masa Utah ) and five ISL  operations totaled 1583 t u (1866 U3O8) in 2006 and 1748 t u (2061 t U3O8) in 2007. In 2008 Rosita became sixth ISL production site before being shut  d own and a total ten under ground mines (four more than during 2007) produced uranium. In total 1503 t u (1,774 t U3O8 was produced in 2008.

In 2009 nuclear regularity commission (NRC) issued generic environment impact statement (EIS) on ISL (or situ recovery IS R)mining in western U.S. This will streamline but not eliminate the requirement for supplementary EIS for each new mine. The NRC expects 17 applications for ISL facilities in next couple of years, into each taking 2 years to  process, including public participation.

Conversion of uranium
The large Honey well Metropolis work plant(MTW) in southern Illinois convert uranium oxide U3O8 to uranium hexafluoride UF6, which then goes to USEC ’s Paducah enrichment operation just across the Ohio river as well as customers to abroad. MTW is only conversion plant in U.S. The facility was built in 1950s under government contract to meet military conversion requirements and began providing UF6 for civilian use in 1960s. Capacity has expanded  from 9000 t u as UF6 per year to 17,600 t u as UF6 today and is expected to increase to 23000 t u by 2020.

De-conversion of depleted uranium

De-conversion of depleted uranium (DU) that remains as by product after enrichment has not so far been under taken large scale in U.S. because of legal problems. There are about over 700000 tons of DU hexafluoride in U.S.

Uranium disposition services (UDS) a joint venture of Areva,  Duratek/ energy solutions and Burn& Roe was awarded a 558 million dollars contract by DOE in 2002 to design and build-De conversation plants at Portsmouth Ohio and Paducah Kentucky . The contract ran to August 2010. These plants use a process developed by Areva which it employs at Richmond Washington and Lingen  Germany. The 13,500 t /years Portsmouth plant started in mid 2010 and 18,000 t/year Paducah one is due to do so by first quarter of 2011. At Portsmouth about 2,50,000 tons of depleted UF6 stored with another 75000 tons expected from Oak Ridge, and Paducah some 4,46,000 tons depleted UF6 stored.

Babcock & Wilcox conversion services won a five year 428 million dollars contract from DOE in December 2010 for uranium De conversion operations at both Portsmouth  and Paducah, using these plants.

Enrichment

The U.S.A. currently operating enrichment plants USE s Paducah, Kentucky facility built by government in early 1950s to provide for military reactors. These large gaseous diffusion plant commissioned in 1952 to military use began providing enrichment uranium for civilian reactors in 1960s. Originally government owned USEC became private corporation in 1998, and leased the two large enrichment plants from DOE. In 2001 it consolidated its enrichment operations at Paducah site after closing the older Portsmouth facility Piketon Ohio. Both plants were large energy intensive and cost to run.

Three new enrichment plants  being built by  other companies are expected to begin operations before 2020. In addition  USEC had started building its own enrichment plant, the American centrifuge plant Piketon Ohio which is due to begin in 2010 but project was put on hold in July 2009.

From 2009, Russia’s Tenex  has signed a number of contracts total some 3 billion dollars covering supplies up to 2020.

Uren co U.S .A. ( formerly national enrichment factory )

Uren co U.S.A. has a major centrifuge enrichment plant at Eunice ,New Mexico. It uses 6th generation Uren co technology from Europe  and was planned by Louisiana Energy services (LES) partnership -comprising Uren co, Exton, Duke power, Entergy and Westinghouse . Construction of the 1.5 billion dollars plant was licensed by NRC in mid 2006 when as agreed the three utilities then passed their share to Uren co and company now subsidiary of Uren co U.S.A. Utility support for venture initially amounting to 3.15 billion dollars in orders -was crucial in persuading the NRC that further U.S. enrichment capacity was required beyond that provided and envisaged by USEC.

FUEL FABRICATION

The U.S. has five fuel fabrication facilities to convert enriched uranium oxide into solid pallets for fuel rods. Areva , Westinghouse , Babcock& Wilcox and General Electric operates fabrication facilities in Virginia, Washington state North Carolina and South Carolina.