Method and apparatus for melting a particulate material
AssigneeBritish Nuclear Fuels plc
InventorsJohn Anthony Schofield, James Lucas
Life of this patent
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Abstract
Apparatus suitable for vitrifying nuclear waste comprises a tunable microwave cavity connected by a first wave guide to a source of microwave energy; cooling coils for cooling the exterior of the cavity; a hopper for loading particulate fusible material to the interior of the cavity; within the cavity a crucible made of melted and re-solidified fusible particulate material; an exit-chamber connected by a second waveguide to a second microwave source; and a pipe for supplying argon gas to the exit chamber so that a plasma torch can be generated. The separating of the crucible form the cavity walls by unmelted material gives significant advantages in case of cleaning and reduced energy consumption.
Claims45
Apparatus for melting a fusible material comprises:
- a housing bounding a microwave cavity and having an exit aperture;
- means for supplying the fusible material to be melted to the interior of the cavity;
- a crucible within the cavity, at least a portion of the crucible being spaced from the housing by a layer of unmelted particulate material, the crucible bounding an opening adapted to hold molten material, the crucible being formed as a solid integral element from melted and re-solidified material;
- means for supplying microwave energy to the cavity of such power that fusible material in the interior of the crucible is melted to form a molten material;
- and
- means for melting material between the molten material and the exit aperture of the cavity.
A method of forming apparatus for melting material comprising:
- supplying a fusible particulate material to the interior of a microwave cavity, the microwave cavity being at least partially bounded by walls;
- cooling the exterior of the cavity;
- supplying microwave energy to the cavity of such power that at least a portion of the fusible particulate material within the cavity melts to form a melt pool, at least a portion of the melt pool being spaced from the cavity walls by a layer of unmelted fusible particulate material;
- and
- causing a portion of the melted material to re-solidify around the melt pool such that a crucible formed from the melted and re-solidified fusible particulate material is provided within the cavity, at least a portion of the crucible being spaced from the cavity walls by the layer of unmelted fusible particulate material.
A method of melting a fusible material comprising:
- supplying particles of fusible material to the interior of a microwave cavity bounded at least in part by walls, the fusible material entering a crucible formed from melted and re-solidified material and spaced apart from the walls of the cavity by a layer of unmelted particulate material;
- and
- melting the fusible material fed to the cavity and crucible by energy being supplied to the crucible in the form of microwave energy, the melted fusible material subsequently being tapped from the crucible by melting the material between the melted fusible material and an exit aperture in the cavity.
Dependencies are inferred from the claim text.