Apparatus for manufacturing coated fuel particles for high-temperature gas-cooled reactor

摘要

[PROBLEMS] To provide an apparatus for manufacturing high quality coated fuel particles by optimizing the design of gas inlet channels and nozzle openings so as to stabilize and uniformize the feeding of a coating material mixed gas into a reaction vessel. [MEANS FOR SOLVING PROBLEMS] The apparatus comprises a fluidized-bed reaction vessel having a gas inlet nozzle at the bottom of the vessel for forming a multilayered coating on each of the surfaces of UO 2 fuel kernels by introducing a coating material mixed gas containing a coating gas and a fluidizing gas from the gas inlet nozzle to the interior thereof under a heated environment while the fuel kernels are fluidized. The gas inlet nozzle comprises a dish-shaped nozzle body fitted into the bottom of the reaction vessel to constitute at least a part of the bottom centre part of the vessel, a plurality of nozzle openings disposed on the nozzle body at positions allocated along a plurality of circular zones which are concentric with each other around the centre axis of said bottom of the reaction vessel, one or more gas inlet channels passing through the nozzle body and communicating with the nozzle openings from the bottom surface side of the vessel, and one or more gas inlet pipes communicating with the one or more gas inlet channels and supplying the coating material mixed gas to the channels from a gas feed system disposed on the outside of the reaction vessel.