IMPROVED METHOD AND APPARATUS FOR MELTING A PARTICULATE MATERIAL

摘要

Apparatus suitable for vitrifying nuclear waste comprises a tunable microwave cavity (10) connected by a first wave guide (16) to a source of microwave energy (18); cooling coils (12) for cooling the exterior of the cavity; a hopper (14) for loading particulate fusible material to the interior of the cavity (10); within the cavity a crucible (32) made of melted and re-solidified fusible particulate material; an exit-chamber (22) connected by a second waveguide (24) to a second microwave source (26); and a pipe (40) for supplying argon gas to the exit chamber (22) so that a plasma torch (31, 33) can be generated. The separating of the crucible (32) from the cavity walls by unmelted material gives significant advantages in case of cleaning and reduced energy consumption.