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Nuclear Fuel Cycle Quality and Standards for your converted material Hex Business at Springfields • Westinghouse will deliver on its promise of providing quality assurance for your company. • We pride ourselves on our engineering expertise and technical ability working to international standards including ISO 9001, 14001 and 18001. • Springfields has a long and successful history in the fuel cycle with over 40 years expertise in Hex conversion. Natural Mining Enrichment Fuel Fabrication Milling Nuclear Conversion Fuel Cycle Power Plant Reprocessing Electricity High Level Waste Storage Spent Fuel Storage www.westinghousenuclear.com Hex Business Rotary Kiln Plant Hex Plant Modern nuclear reactor designs such as Pressurised Water and Light Water Reactors To Atmosphere Uranium Trioxide UO – UF Conversion UF – UF Conversion UO 3 4 4 6 need nuclear fuel, made from Uranium Dioxide. 3 UO3 is transported to Kiln Plant in drums where it Uranium Hexafluoride is produced by the reaction UO To Atmosphere 3 is transferred onto a conveyor system. From here of UF with elemental gaseous fluorine in a Uranium Hexafluoride (UF6 ) is an essential intermediate product used in the Feed Hopper 4 Run Off Discharge the drums are delivered into the process via a fluidised bed reactor at 475°C. The fluorine manufacture of Uranium Dioxide fuels. Water UF6 mechanised tipping system. is produced by the electrolysis of anhydrous Condensers Hydration is the first stage in the treatment of hydrofluoric acid (AHF) in a potassium bi-fluoride Vac Back Air UO for the production of UF . electrolyte. 3 4 Secondary Meeting World Demands Advanced Technology Water Glycol Hydrator Heating & Cooling UO2 Transfer AHF Primary The Springfields Hex facilities are capable of Both plants demonstrate proven and state- To Scrubbers Hopper To Scrubbers H2 Transport Rotary Off-Gas Cylinder producing up to 5,500 tU of (UF6) annually, of-the-art technology. Automated handling Rotary Hydrofluorination Filtration incorporating the latest technology for safe, facilities are incorporated for both product Reduction Kiln Kiln Main efficient and economic processing. The UF and waste streams which, when combined Reactor 6 Uranium Uranium Tetrafluoride Uranium Hexafluoride UF6 UF Calcium produced is exported to enrichment facilities with secondary containment and advanced 4 to Enrichment Facility Tetrafluoride Fluoride UF4 CaF throughout the world in order to satisfy the ventilation systems, lead to greatly reduced 2 Feed Secondary Stock Hoppers requirements for nuclear fuel production. employee radiation exposure. Uranium Hopper Dioxide Primary UO2 The plants are designed to be intrinsically Recycle Gas To Hexafluoride UF Production safe, incorporating automatic shutdown and Production 6 Hydrogen to remote control as key features. Atmosphere Nitrogen UO3 powder is fed into a hydrator where dilute nitric and sulphuric acids are added to increase the AHF Gas Recycle Springfields UF6 production is split into two Equipment is supported on flexible mountings Compressor porosity of the powder and aid the chemical conversion process. Nitrogen key phases of its chemical conversion process. where necessary; to allow building movement Fluorine UF leaves the reactor as a gas with other process The first phase of the process occurs in the and additional bracing is incorporated into Reduction is the second stage in UF production. UO hydrate is fed into a hot rotating kiln and is 6 4 3 gases and solids. Filters remove the solids, before Rotary Kiln Plant converting Uranium Trioxide the framework of the building for increased gradually converted into UO (Uranium Dioxide) in the presence of hydrogen gas. The main reactions in 2 the UF enters the condensers. UF changes (UO ) into Uranium Tetrafluoride (UF ). The protection in the unlikely case of a seismic the reduction kiln can be split into two: 6 6 3 4 phases from a gas to a solid by circulating cooled second phase occurs in Hex Plant, where UF4 event. UO .H O Ú UO + H O This is the dehydration stage which is endothermic. refrigerant fluid through condenser tubes and is converted to produce the desired chemical 3 2 3 2 UO + H Ú UO + H O This is the reduction stage which is exothermic. jackets at a temperature of -30°C. When full, compound Uranium Hexafluoride (UF ). 3 2 2 2 6 Fluorine the condenser is taken out of line and heated to The Rotary Kiln Plant and Hex Plant will be Cells 90°C to allow the UF6 to be run-off as a liquid to Hydrofluorination is the third stage. The UO2 powder is fed into a hot rotating kiln and is gradually explained in more detail on the following the Hex filling station. Uncondensed gases are converted into UF4 by reaction with gaseous hydrogen fluoride. pages. recycled back to the reactor. UO2 + 4HF Ú UF4 + 2H2O This reaction is exothermic. At the filling station a Hex cylinder is connected to a pipeline from the condensers within a secondary Once converted, UF4 is transported to stock hoppers where it is held temporarily before being containment area. Once filled the cylinders are left to cool where the Hex solidifies and creates a pneumatically transported via pipe line to the Hex Plant. vacuum. The UF6 is now ready to be transported to enrichment plants around the world. hex plant complex hex transport cylinders visitors information area UO3 drum tipper facility kiln deck UF4 stock hopper area fluorine cell room condenser room control room.
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