Fuel inventory

A D—T fusion reactor is expected to have a tritium inventory of a few kilograms. Tritium is a relatively short-Hved (12.36 year half-life) and benign (beta emitter) radioactive material, and represents a radiological ha2ard many orders of magnitude less than does the fuel inventory in a fission reactor. Clearly, however, fusion reactors must be designed to preclude the accidental release of tritium or any other volatile radioactive material. There is no need to have fissile materials present in a fusion reactor, and relatively simple inspection techniques should suffice to prevent any clandestine breeding of fissile materials, eg, for potential weapons diversion. 

Oil and gas operations today are almost universally constitute a continuous run operation versus a batch process. Once fluids and gases are found and developed they are transported from one process to another without delay or interruption. This provides improved economics, but also increases the fuel inventories and thereby inherent risk in the operation. 

Generally the highest risks in offshore facilities are blowouts, transportation impacts and process upsets. Where inadequate isolation means are provided for either wellheads or pipeline connections to the installation considerable fuel inventories will be available to an incident. 

For more than a century, fossil fuels have been extensively used to satisfy human s needs. The application of fossil fuels is very diverse—producing electricity, powering transportation activities, providing raw materials for clothes and construction. Flowever, the world s fossil fuels inventory is rapidly declining and soon demand will outstrip production. Based on current consumption rates, fossil fuel supply will only last for a few centuries. 

The 1060-MWe PWR discussed in Sec. 3.4 is to be operated with steady, four-zone modified scatter refueling, with 1.0 year between successive refuelings. The availability-based capacity factor is 0.8 and the refueling downtime is 0.15 year. The reactor fuel inventory is 88.961 MT heavy metal. 

Initial core Equilibrium core Fuel inventory Core (U+Pu metal)... 

The fuel inventory balance is shown in Table 2. The amount of Pu is 1.3tons at start up of the 4S core and 1.2tons remain after ten years of operation. In this sense, the 4S core could be called a plutonium burning storage cote. 

The retention period for narrative logs, facility drawings, routine release records or estimates, and fuel inventories is the "life of the facility." The retention period for other records, such as unusual occurrence reports involving releases to the enwonment, contamination, and personnel exposure dose records, is 75 years. 

The fractional increase in fuel inventory in time AT for an expanding economy having a doubling time is... 

Then the resource requirements in metric tons of uranium, MTU, which must be mined just to supply the fuel inventory for each megawatt(e) of power installed per year is... 

A parametric study carried out in order to establish the design orientations of burner cores taught us first that a considerable reduction of the fuel inventory (or dilution ) is always necessary to be able to operate a large core with a high plutonium content and therefore with an attractive plutonium burning performance. This dilution results in a decrease in in-pile fuel residence time as well as in a reduction (favourable) of the sodium void reactivity, whereas a decrease of the uranium content of the fuel brings about a reduction of the Doppler effect, a decrease of the conversion ratio which causes a daily reactivity loss ttiat makes it difficult to achieve long irradiation cycles, as well as a reduction of tiie delayed neutron fraction. 

Fuel inventory that should be made up so as to provide a small (comparable to 1 total reactivity margin due to compensation of bumup of fissile nuclides by their full reproduction (the optimal CBR being roughly equal to 1.05) and owing to the small power effect of reactivity. 

The reactor core is built of fuel assemblies with the same fuel composition and fuel rod pitch. Radial equalization of the FA power and the coolant temperature gains relies on profiling of the fuel inventory and lead flow, with the former provided by using fuel rods of a smaller diameter in the central assemblies and those of a larger diameter in the peripheral ones. The equalized distributions are kept stable owing to the same fuel composition in all assemblies, subject to the condition of CBR s 1. 

Fuel inventory (tonnes of heavy metal) 109 uranium metal... 

Fuel material Natural UO2 Fuel inventory (tons of heavy metal) 531 of U Average core power density (kW/litre) 12.8 kW/L Average fuel power density (kW/kgU) 25.4 kW/kgU Maximum linear power (W/m). 54 kW/m of fiiel rod Average discharge bumup (MWd/t) 6167 MWd/t of U Initial enrichment (wt%) 0.711 wt%... 

Fuel inventory (tones of heavy metal) 47 tonnes of UOj... 

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