Provided is an induction heating device with which discharging can be easily avoided even when a large electric current is used. The induction heating device comprises a high-frequency power supply provided with a connection portion for an alternating-current power supply, and a heating coil portion connected to the high-frequency power supply. In the heating coil portion, a plurality of coils include n coils surrounding a cavity portion in a plane, wherein the plurality of coils are mutually connected in series via one of a plurality of capacitors.

Methods for disposing of munition components may include separating propellants from heavy metal penetrators and disposing of those separated components into different types of geological formations. The initially solid form propellants may be converted into a stable liquified propellant form, by a particular disclosed process, that may be injected within salt water (injection) disposal wells, where distal portions of such salt water disposal wells may be located in a geological formation of substantially at least one salt. The separated heavy metal penetrators (with or without their associated projectile jackets) may be disposed of within human-made caverns, where such human-made caverns may be located within a deep geological formation that is often 2,000 feet or more below the Earth's surface. The heavy metal penetrators may include uranium (depleted uranium). Portions of a given munition, to be disposed of, may be radioactive.

The present invention relates to a plasma furnace which can efficiently treat various types of waste in large amounts. The plasma furnace comprises a melting chamber 101 for accommodating a melt, an upper surface forming the upper portion of the melting chamber 101 with a horizontal upper surface 111 and an inclined upper surface 112 having a slope with respect to the horizontal upper surface 111, a melt discharge portion 130 formed through a bottom surface of the melting chamber for discharging molten material therethrough, and an input apparatus 120 having a slope for inputting waste into the melting chamber 101, and the mixed type plasma torch 191, 192 provided on the inclined upper surface 112 with a slope for generating melting heat in the melting chamber 101.

A single integrated system for recycling used nuclear fuel (UNF) emerging from a reactor has a decladding vessel separating fuel pellets from nuclear fuel rods via oxidation to produce U.sub.3O.sub.8. A fluorination vessel is coupled to the decladding vessel to remove hexafluorides from the U.sub.3O.sub.8 produced by the decladding vessel. An electrowinning vessel is coupled to the fluorination vessel removing plutonium and actinides via electrowinning.

The present invention provides solidified radioactive waste into which a titanium-containing adsorbent having a radioactive element adsorbed thereto is vitrified, the solidified radioactive waste being capable of confining a large amount of the titanium-containing adsorbent having a radioactive element adsorbed thereto, and furthermore elution of the radioactive element from the vitrified waste being suppressed. A method for producing solidified radioactive waste of the present invention is characterized by including heat-melting a mixture that includes a titanium-containing adsorbent having a radioactive element adsorbed thereto, a SiO.sub.2 source, and an M.sub.2O source (M represents an alkali metal element) to form vitrified waste, and the titanium-containing adsorbent is preferably one or two or more selected from silicotitanate, an alkali nonatitanate, and titanium hydroxide.

The present invention relates to a plasma furnace which can efficiently treat various types of waste in large amounts. The plasma furnace comprises a melting chamber 101 for accommodating a melt, an upper surface forming the upper portion of the melting chamber 101 with a horizontal upper surface 111 and an inclined upper surface 112 having a slope with respect to the horizontal upper surface 111, a melt discharge portion 130 formed through a bottom surface of the melting chamber for discharging molten material therethrough, and an input apparatus 120 having a slope for inputting waste into the melting chamber 101, and the mixed type plasma torch 191, 192 provided on the inclined upper surface 112 with a slope for generating melting heat in the melting chamber 101.

The method for the long-term storage of waste nuclear fuel of a nuclear reactor consists in that, first, prior to the waste fuel assembly of the nuclear reactor being disposed in a steel case and the latter being hermetically sealed with a cover, a material which is chemically inert in relation to the material of the casing of the fuel elements of the waste fuel assemblies, to the material of the body of the case, to air and to water, is arranged in the steel case, the steel case is mounted in a heating device, the steel case is heated along with the material arranged in said steel case until said material passes into a liquid state, and then the waste fuel assembly which has been extracted from the nuclear reactor is arranged in the steel case in such a way that the fuel part of the fuel elements of the waste fuel assemblies is lower than the level of the liquid material in the steel case, the waste fuel assembly is fixed in this position, and the case is hermetically sealed by the cover, whereupon the hermetically sealed steel case is extracted from the heating device and mounted in a storage facility which is cooled by atmospheric air. This technical solution makes it possible to ensure long-term safe storage of waste fuel assemblies of a nuclear reactor in storage facilities with cooling using atmospheric air, in particular with natural circulation of atmospheric air, and also to transport the waste fuel assemblies to a factory for processing so as to ensure an increased level of safety.

The present invention relates to a method of adjusting the oxoacidity of a molten metal hydroxide salt, the method comprising the steps of: estimating a target concentration of at least one of H.sub.2O, O.sup.2, and OH in a molten salt of a metal hydroxide; providing an oxoacidity control component; and contacting the oxoacidity control component with the molten salt of a metal hydroxide to adjust the oxoacidity of the molten salt of a metal hydroxide. The method allows better utilisation of the available temperature range for a molten salt of a metal hydroxide by reducing the corrosive nature of the metal hydroxide.

Provided is an ion exchange resin volume reduction apparatus in which the ignition of plasma is facilitated and the plasma is prevented from extinguishing. A volume reduction apparatus according to aspects of the present invention includes a stage carrying thereon a resin to be treated, a CCP power source, and an ICP power source. The volume reduction apparatus according to a certain aspect of the present invention is provided with a supply mechanism, and the CCP power source continues operating when the resin to be treated is supplied in a depressurized state to a vacuum vessel. In the volume reduction apparatus according to a certain aspect of the present invention, the CCP power source continues operating when a gas condition under which gas is supplied into the vacuum vessel is changed.

A single integrated system for recycling used nuclear fuel (UNF) emerging from a reactor has a decladding vessel separating fuel pellets from nuclear fuel rods via oxidation to produce U.sub.3O.sub.8. A fluorination vessel is coupled to the decladding vessel to remove hexafluorides from the U.sub.3O.sub.8 produced by the decladding vessel. An electrowinning vessel is coupled to the fluorination vessel removing plutonium and actinides via electrowinning.