Fuel and Target Assemblies

The Disasseinhly Basin cooling syst provides cooling of irradiated components. Discharged fuel and target assemblies generate fission product decay heat. These assemblies are stored in the VTS basin until th are moved to the MB in accordance with approved procedures. 

The fuel and target assemblies have been removed firom die Reactor Tank therefi)re, no fissOe material b present in the Process Room. 

These activities are expected to reduce the initiation of new pitting corrosion and slow down the existing, basin corrosion processes. With this improved ba storage environment, fuel and target assemblies are expected to corrode at a slower rate than th have previousty. 

The aluminum cladding of fiiel and target assemblies provides foe primary confinement for the fission products, fissile materials, and other radionuclides contained in the fuel and target assemblies. The thickness of foe cladding varies firom 0.02 to 0.03 inches. 

The K-Reactor tank is a 15-foot-high cylinder with a diameter of about 16 feet. Six tapered inlet nozzles are uniformly spaced around the circumference of the coolant inlet plenum and six outlet nozzles are uniformly spaced around the circumference of the tank bottom. The plenum and top tube sheet are supported independently of the reactor shell (1/2-inch thick) and bottom tube sheet by a bearing ring which is supported by 12 beams anchored in concrete. The top tube sheet is supported above the main tank shell by a 3/16-inch-thick expansion ring. The tank shell and bottom tube sheet are supported by 12 bearing pad assemblies. The reactor contains positions for 597 fuel and target assemblies, which are supported by the water plenum and top shield. 

No material of record demonstrating the seismic adequacy of the reactor internals was identified. The DOE staff has since performed a detailed preliminary analysis of the fuel and target assemblies. Although preliminary results from this analysis are satisfactory, this item is open pending documentation of the final results of this analysis. 

Initial seismic analyses of the top tube sheet support and bottom tank support were inadequate. Preliminary results from the DOE staff confirmatory analyses demonstrate the adequacy of the supports. However, a significant input parameter for these analyses is the load from the fuel and target assemblies analyzed by the DOE staff. An analysis of top and bottom supports was performed that included loads from the fuel and target assemblies. Results of this confirmatory analysis still require documentation to close this issue. 

WSRC, DPSOL 321-1455 I, "Certification of Mark 22 Fuel and Target Assemblies."... 

The fissile mateiiab stored in the L-Reactor Disassembly Basin are included in Marie 16B and Mark 31A fiiel and target assemblies, calibration sources, and thorium slugs. The fissile materials stored in the P-Reactor Disassembly Basin are included in Marie 42, Mark 16B, and Mark 22 fuel assembUes a Pu-Be source and Ai 243 slugs. 

The op tors are required by procedure to separate fuel and target portions of an assembly before placing the target into a stack. 

In both cases, the net effect is the same a stifling of coolant flow to subchannels and ultimately to the assembly... Precursor criteria have been selected for the FI and ECS phases that preclude gross fuel and target surface dryout and any subsequent fuel damage. 

Since most of the fuel assemblies and targets have now been stored in the K-, L-, and P-Reactor Disassembly Basins for over 5 years without exceeding the radionuclide operating limits and with only small accumulations of fissile material in the sludge at the bottom of the badns and in the... 

Cost targets exist for all parts of the fuel cell for bipolar plates, from 10/kW (2004) to 3/kW in 2015 for electrocatalysts, from 40/kW (2005) to 3/kW in 2015 and for membrane electrode assemblies (MEA), from 50/kW (2005) to 5/kW in 2015 (Freedom Car, 2005 these cost targets are somewhat different from those mentioned by the IEA (2005)). Since 2004, the number of fuel-cell cars has been growing and at the time of writing they numbered approximately 1000 worldwide there are also around 100 fuel-cell buses in use worldwide in several demonstration projects. But these cars are produced as individual (hand-built) models and are extremely expensive, with production costs per vehicle currently estimated at around one million large-scale production is not expected before 2015, see Section 13.1. 

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