The present invention relates to a sealed plasma melting furnace for treating low- and intermediate-level radioactive waste, which allows the secondary pollutants to be minimized. The sealed plasma melting furnace includes: a waste supply chamber communicatively provided with a hopper; a pyrolysis chamber channel communicatively coupled with the waste supply chamber; a pyrolysis chamber having a burner mounted thereon; a melting chamber channel guiding the waste transferred from the pyrolysis chamber communicatively provided therewith to fall down; a melting chamber provided with a furnace interior portion accommodating a molten substance on a bottom surface thereof; a processed molten substance discharge channel discharging the processed molten substance generated in the melting chamber; a secondary combustion chamber channel inducing and exhausting an off-gas flow generated in the melting chamber; and a secondary combustion chamber inducing complete combustion of the off-gas input from the secondary combustion chamber channel.

The invention relates to the field of environmental protection, more specifically to the field of processing radioactive waste, and can he used for the safe and effective handling of a large quantity of liquid radioactive waste of various activity levels that has been formed as the result of decontaminating protective equipment of boxes and chambers, and makes it possible to decrease the volume of stored waste by solidifying same and incorporating same into a ceramic matrix. For this purpose, radioactive solutions after decontamination of surfaces of protective equipment are evaporated as alkaline and acidic solutions containing sodium hydroxide, potassium permanganate, oxalic acid, and nitric acid until a solid residue forms, and are calcined, and the calcinate is mixed with components of a fusion mixture containing oxides of titanium, calcium, iron (III), zirconium, and manganese (IV) and aluminum in a specified ratio, and fused.

A method for thermal volume reduction of waste material contaminated with radionuclides includes feeding the waste material into a fluidized bed reactor, injecting fluidizing gas into the fluidized bed reactor to fluidize bed media in the fluidized bed reactor, and decomposing the waste material in the fluidized bed reactor. A system for thermal volume reduction of the waste material includes one or more of a feedstock preparation and handling system, a fluidized bed reactor system, a solids separation system, and an off-gas treatment system. The method and system may be used to effectively reduce the volume or radioactive wastes generated from the operation of nuclear facilities such as nuclear power plants including wastes such as spent ion exchange resin, spent granular activated carbon, and dry active waste. The majority of the organic content in the waste material is converted into carbon dioxide and steam and the solids, including the radionuclides, are converted into a waterless stable final product that is suitable for disposal or long-term storage.

The invention relates to the field of environmental protection, more specifically to the field of processing radioactive waste, and can he used for the safe and effective handling of a large quantity of liquid radioactive waste of various activity levels that has been formed as the result of decontaminating protective equipment of boxes and chambers, and makes it possible to decrease the volume of stored waste by solidifying same and incorporating same into a ceramic matrix. For this purpose, radioactive solutions after decontamination of surfaces of protective equipment are evaporated as alkaline and acidic solutions containing sodium hydroxide, potassium permanganate, oxalic acid, and nitric acid until a solid residue forms, and are calcined, and the calcinate is mixed with components of a fusion mixture containing oxides of titanium, calcium, iron (III), zirconium, and manganese (IV) and aluminum in a specified ratio, and fused.

The present invention relates to a sealed plasma melting furnace for treating low- and intermediate-level radioactive waste, which allows the secondary pollutants to be minimized. The sealed plasma melting furnace includes: a waste supply chamber communicatively provided with a hopper; a pyrolysis chamber channel communicatively coupled with the waste supply chamber; a pyrolysis chamber having a burner mounted thereon; a melting chamber channel guiding the waste transferred from the pyrolysis chamber communicatively provided therewith to fall down; a melting chamber provided with a furnace interior portion accommodating a molten substance on a bottom surface thereof; a processed molten substance discharge channel discharging the processed molten substance generated in the melting chamber; a secondary combustion chamber channel inducing and exhausting an off-gas flow generated in the melting chamber; and a secondary combustion chamber inducing complete combustion of the off-gas input from the secondary combustion chamber channel.

The present invention relates to a sealed plasma melting furnace for treating low- and intermediate-level radioactive waste, which allows the secondary pollutants to be minimized. The sealed plasma melting furnace includes: a waste supply chamber communicatively provided with a hopper; a pyrolysis chamber channel communicatively coupled with the waste supply chamber; a pyrolysis chamber having a burner mounted thereon; a melting chamber channel guiding the waste transferred from the pyrolysis chamber communicatively provided therewith to fall down; a melting chamber provided with a furnace interior portion accommodating a molten substance on a bottom surface thereof; a processed molten substance discharge channel discharging the processed molten substance generated in the melting chamber; a secondary combustion chamber channel inducing and exhausting an off-gas flow generated in the melting chamber; and a secondary combustion chamber inducing complete combustion of the off-gas input from the secondary combustion chamber channel.

Apparatus and methods for treating radioactive material, in particular for cleaning radioactive contaminated water, are described. One apparatus comprises a process chamber with a combustion zone for generating an oxygen rich gas and an oxidation zone, which is arranged to receive the oxygen rich gas from the combustion zone. The process chamber further comprises a feed opening for feeding the radioactive material into the oxidation zone and is configured to use the oxygen rich gas for oxidizing the radioactive material to obtain oxidized material. The apparatus further comprises a separation device operationally connected to an outlet of the process chamber and configured to at least partly separate the oxidized material into a gaseous fluid and a non-gaseous residue. This way a greatly reduced volume of the radioactive material is achieved, enabling safe and efficient handling and/or compact and space-saving disposal of the radioactive material.

A method for thermal volume reduction of waste material contaminated with radionuclides includes feeding the waste material into a fluidized bed reactor, injecting fluidizing gas into the fluidized bed reactor to fluidize bed media in the fluidized bed reactor, and decomposing the waste material in the fluidized bed reactor. A system for thermal volume reduction of the waste material includes one or more of a feedstock preparation and handling system, a fluidized bed reactor system, a solids separation system, and an off-gas treatment system. The method and system may be used to effectively reduce the volume or radioactive wastes generated from the operation of nuclear facilities such as nuclear power plants including wastes such as spent ion exchange resin, spent granular activated carbon, and dry active waste. The majority of the organic content in the waste material is converted into carbon dioxide and steam and the solids, including the radionuclides, are converted into a waterless stable final product that is suitable for disposal or long-term storage.

A method for treating before calcination a nitric aqueous solution comprising at least one radionuclide and ruthenium is provided. The method comprises a step for adding to the solution a compound selected from lignins, lignocelluloses, optionally as salts and mixtures thereof.

A method for treating before calcination a nitric aqueous solution comprising at least one radionuclide and ruthenium is provided. The method comprises a step for adding to the solution a compound selected from lignins, lignocelluloses, optionally as salts and mixtures thereof.