Abstract: A treatment method for a used ion exchange resin, includes: bringing a used ion exchange resin into contact with a reaction solution, the used ion exchange resin having an ion exchange group with at least a radionuclide or a heavy metal element adsorbed thereon, and the reaction solution containing an iron compound, hydrogen peroxide, and ozone; separating at least a part of the reaction solution in contact with the used ion exchange resin from the used ion exchange resin; and decomposing an organic component contained in the reaction solution separated from the used ion exchange resin.

Abstract: A method for decontaminating the nickel-based alloy includes oxidization of an oxide film accumulating radioactive nuclides with a first oxidizing agent to elute nickel into a solvent and thus to transform into a low-nickel film (S13 to S15). Elution amounts of Nickel, Chromium, and iron in the solvent are measured in the step S15 of the first oxidation step. Based on the elution amount, a second oxidizing agent is selected in the step S16. With the second oxidizing agent, the low-nickel film is oxidized to elute Chromium and thus to transform into an iron-concentrated film (S17 to S19). The iron-concentrated film is reduced with a reducing agent after the second oxidizing step including the steps of S13 to S19 to be dissolved and thus to be removed (S22).

Abstract: A treatment method for a used ion exchange resin, includes: bringing a used ion exchange resin into contact with a reaction solution, the used ion exchange resin having an ion exchange group with at least a radionuclide or a heavy metal element adsorbed thereon, and the reaction solution containing an iron compound, hydrogen peroxide, and ozone; separating at least a part of the reaction solution in contact with the used ion exchange resin from the used ion exchange resin; and decomposing an organic component contained in the reaction solution separated from the used ion exchange resin.

Abstract: A radioactive substance is effectively suppressed by an oxide-film removal step of removing an oxide film on a metallic material surface with which a coolant containing the radioactive substance comes in contact, and a titanium-oxide deposition step of depositing a titanium oxide on the metallic material surface after the oxide film has been removed.

Abstract: According to one embodiment, a process for producing rare metals includes the steps of: recovering a first-residue solution through a primary target metal extracted by leaching a mineral resource; extracting a perrhenic acid ion contained in the first-residue solution with at least one of an anion exchange resin and a first-organic solvent; back extracting the perrhenic acid ion contained in the anion exchange resin or the first-organic solvent to a first-eluant; and electrolyzing the back extracted first-eluant to collect a rhenium at a cathode.

Abstract: A radiation exposure reduction method includes the steps of: injecting iron into a coolant which flows from the reactor cooling system to the reactor core in a nuclear power plant; and ferritizing and fixing radionuclides or parent nuclides thereof, which are contained in the coolant, on the surface of a reactor core structure, wherein an iron citrate which is soluble organic iron, or iron oxalate or iron fumarate which has a particle diameter of 3 ?m or less, is used as the iron to be injected into the coolant.

Abstract: A chemical decontamination apparatus of the present invention chemically dissolves radioactive substance-containing oxide films formed or adhering on the surface of a decontamination object by using ozone water to conduct decontamination. The chemical decontamination apparatus includes an ozone generating unit for generating ozone gas, an ozone supplying device for supplying the generated ozone gas to an ozone supplying unit in water, and a sintered metal element 37 which is disposed in the ozone supplying unit and to which ozone gas is supplied from the ozone supplying device. The ozone gas supplied to a sintered metal element interior from the ozone supplying device is allowed to flow out of the element into water so as to generate ozone water.

Abstract: According to one embodiment, a process for producing rare metals includes the steps of: recovering a first-residue solution through a primary target metal extracted by leaching a mineral resource; extracting a perrhenic acid ion contained in the first-residue solution with at least one of an anion exchange resin and a first-organic solvent; back extracting the perrhenic acid ion contained in the anion exchange resin or the first-organic solvent to a first-eluant; and electrolyzing the back extracted first-eluant to collect a rhenium at a cathode.

Abstract: A radioactive substance is effectively suppressed by an oxide-film removal step of removing an oxide film on a metallic material surface with which a coolant containing the radioactive substance comes in contact, and a titanium-oxide deposition step of depositing a titanium oxide on the metallic material surface after the oxide film has been removed.

Abstract: A radiation exposure reduction method includes the steps of: injecting iron into a coolant which flows from the reactor cooling system to the reactor core in a nuclear power plant; and ferritizing and fixing radionuclides or parent nuclides thereof, which are contained in the coolant, on the surface of a reactor core structure, wherein an iron citrate which is soluble organic iron, or iron oxalate or iron fumarate which has a particle diameter of 3 ?m or less, is used as the iron to be injected into the coolant.

Abstract: A system for chemically decontaminating radioactive material.

Abstract: A chemical decontamination apparatus of the present invention chemically dissolves radioactive substance-containing oxide films formed or adhering on the surface of a decontamination object by using ozone water to conduct decontamination. The chemical decontamination apparatus includes an ozone generating unit for generating ozone gas, an ozone supplying device for supplying the generated ozone gas to an ozone supplying unit in water, and a sintered metal element 37 which is disposed in the ozone supplying unit and to which ozone gas is supplied from the ozone supplying device. The ozone gas supplied to a sintered metal element interior from the ozone supplying device is allowed to flow out of the element into water so as to generate ozone water.

Abstract: A system for chemically decontaminating radioactive material.

Abstract: Chemical decontamination method of dissolving oxide film adhered to contaminated component including, preparing decontamination solution in which ozone is dissolved and oxidation additive agent, which suppresses corrosion of metal base of the contaminated component, is added, and applying the decontamination solution to the contaminated component, thereby to remove the oxide film by oxidation.

Abstract: A system for chemically decontaminating radioactive material.

Abstract: A system for chemically decontaminating radioactive material.

Abstract: A method for chemically decontaminating radioactive material. The method includes reducing-dissolving step for setting surface of radioactive material in contact with reducing decontamination liquid including mono-carboxylic acid and di-carboxylic acid as dissolvent; and oxidizing-dissolving step for setting the surface of the radioactive material in contact with oxidizing decontamination liquid including oxidizer. The method may include repeated pairs of steps, each pair including the reducing-dissolving step and the oxidizing-dissolving step. The mono-carboxylic acid may include formic acid, and the di-carboxylic acid includes oxalic acid. The oxidizer may be ozone, permanganic acid or permanganate.

Abstract: A method for chemically decontaminating radioactive material. The method includes reducing-dissolving step for setting surface of radioactive material in contact with reducing decontamination liquid including mono-carboxylic acid and di-carboxylic acid as dissolvent; and oxidizing-dissolving step for setting the surface of the radioactive material in contact with oxidizing decontamination liquid including oxidizer. The method may include repeated pairs of steps, each pair including the reducing-dissolving step and the oxidizing-dissolving step. The mono-carboxylic acid may include formic acid, and the di-carboxylic acid includes oxalic acid. The oxidizer may be ozone, permanganic acid or permanganate.

Abstract: Chemical decontamination method of dissolving oxide film adhered to contaminated component including, preparing decontamination solution in which ozone is dissolved and oxidation additive agent, which suppresses corrosion of metal base of the contaminated component, is added, and applying the decontamination solution to the contaminated component, thereby to remove the oxide film by oxidation.

Abstract: Ozone gas having a high ozone concentration is generated by a solid electrolyte electrolytic process. An ozone solution is prepared by injecting the ozone gas into an acidic solution of pH 6 or below. The ozone solution heated at a temperature in the range of 50° to 90° C. is supplied to a contaminated object to oxidize and dissolve a chromium oxide film by an oxidizing dissolving process. The ozone solution used in the oxidizing dissolving process is irradiated with ultraviolet rays to decompose ozone contained in the ozone solution, the ozone solution is passed through an ion-exchange resin to remove ions contained in the ozone solution. An oxalic acid solution is supplied to the contaminated object to dissolve an iron oxide film by a reductive dissolving process.