Densification plant processes

To minimize the effects of fuel densification, plant procedures limit the maximum permissible rate at which power may be increased to ensure that the temperature will not exceed 1200 C during a loss of coolant accident. This allows the fuel pellets to shift slowly, with less chance of becoming jammed during the densification process, which in turn reduces the chance of cladding failure. 

Basic process steps in the production of ROEMMC fuel pellets are DRYING of the wet raw material, SIZE REDUCTION of the dry material, and DENSIFICATION of the dry, fine material. The thermal energy for the drying process is derived from the combustion of fines separated from the dry, fine material. The only external energy input to the production of pellets is electrical. The hardware embodiment of these processes is described in these paragraphs, as employed in the Stillwater, Minnesota, plant. This plant was designed to have an output production rate of 150 tons per day, continuous operation. 

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