ASN Report 2017

382 ASN report on the state of nuclear safety and radiation protection in France in 2017 Chapter 13  - Nuclear fuel cycle installations The Eurodif gaseous diffusion enrichment plant – BNI 93 This finally shut down facility is the subject of a decommissioning application and is dealt with in chapter 15. The Georges Besse II gas centrifuge enrichment plant – BNI 168 BNI 168, called Georges Besse II (GB II), licensed in 2007 and operated by the Société d’enrichissement du Tricastin (SET), is a plant enriching uranium by means of gas centrifugation. This process involves injecting UF 6 into a cylindrical vessel rotating at very high speed. The centrifugal force concentrates the heavier molecules (containing uranium-238) on the periphery, while the lighter ones (containing uranium-235) are recovered in the centre. By combining several centrifuges, creating a cascade, it is then possible to recover a stream enriched with fissile U-235 isotope and a depleted stream. This process has two key advantages over the gaseous diffusion process used in the former Eurodif enrichment plant: it consumes far less electrical energy (75 MWe as against 3,000 MWe) and is safer because the quantities of material present in the centrifuge cascades are far smaller (6 tonnes in GB II instead of 3,000 tonnes in Eurodif) and utilised in gas form at below atmospheric pressure. The plant comprises two enrichment units (South and North units) and a support unit, the REC II, for which ASN authorised commissioning in 2014. At the beginning of 2009, ASN authorised commissioning of the South unit, comprising eight modules, followed in 2013 by the North unit, comprising six modules, the first two of which are designed to enrich the uranium from spent fuel reprocessing. Enrichment of the uranium resulting from reprocessing in the facility, requiring prior authorisation from ASN, has never been implemented. In 2017, the level of safety of the GB II plant was satisfactory. The technologies utilised in the facility enable high standards of safety, radiation protection and environmental protection to be maintained. The gradual entry into production of the enrichment cascades 3 is now complete. The plant’s output should therefore rise in 2018. 3 . Referring here to a group of interconnected centrifuges enabling a certain level of enrichment to be achieved. La Hague plant UP3 UP2-800 STE3 THE INSTALLATIONS of the fuel cycle in operation or undergoing decommissioning Areva NP plants in Romans-sur-Isère FBFC Cerca Tricastin site Comurhex GB II TU5 et W Socatri Uranium storage areas in Tricastin P35 Atlas Marcoule site Mélox Malvési site Comurhex