Solid nanocomposite material comprising nanoparticles of a hexacyanometallate or octacyanometallate of an alkali metal and of a transition metal, of formula [Alk.sup.+.sub.x]M.sup.n+[M′(CN).sub.m].sup.z− in which Alk is an alkali metal, x is 1 or 2, M is a transition metal, n is 2 or 3, M′ is a transition metal, m is 6 or 8, z is 3 or 4, attached to at least one surface of a porous inorganic solid support, in which the nanoparticles are attached by adsorption to the at least one surface of the solid support, and in which the surface is a basic surface. Method for preparing this material. Method for extracting at least one metal cation from a liquid medium containing it, wherein the liquid medium is brought into contact with the material.

Provided is a method of treating radioactive liquid waste which reduces the amount of radioactive waste to be generated and is capable of removing a radioactive nuclide from radioactive liquid waste to the extent that the concentration thereof is less than or equal to the measurement lower limit using a simple apparatus configuration. A filtration device is connected to a colloid removal device by a connection pipe. An adsorption tower positioned at the highest stream of an adsorption device is connected to the colloid removal device by a connection pipe. The colloid removal device includes an electrostatic filter. Respective adsorption towers in the adsorption device are sequentially connected by a pipe. A discharge pipe is connected to the adsorption tower positioned at the lowest stream of the adsorption device. Radioactive liquid waste, containing particles having a particle diameter of 1 μm or greater, negatively charged colloids, and a radioactive nuclide, is supplied to the filtration device. The particles having a particle diameter of 1 μm or greater are removed by the filtration device and the negatively charged colloids are removed by the electrostatic filter that is positively charged. The radioactive nuclide is removed by the adsorption tower.

Provided is a method of treating radioactive liquid waste which reduces the amount of radioactive waste to be generated and is capable of removing a radioactive nuclide from radioactive liquid waste to the extent that the concentration thereof is less than or equal to the measurement lower limit using a simple apparatus configuration. A filtration device is connected to a colloid removal device by a connection pipe. An adsorption tower positioned at the highest stream of an adsorption device is connected to the colloid removal device by a connection pipe. The colloid removal device includes an electrostatic filter. Respective adsorption towers in the adsorption device are sequentially connected by a pipe. A discharge pipe is connected to the adsorption tower positioned at the lowest stream of the adsorption device. Radioactive liquid waste, containing particles having a particle diameter of 1 μm or greater, negatively charged colloids, and a radioactive nuclide, is supplied to the filtration device. The particles having a particle diameter of 1 μm or greater are removed by the filtration device and the negatively charged colloids are removed by the electrostatic filter that is positively charged. The radioactive nuclide is removed by the adsorption tower.

A method of follow-up decontamination operation for the polluted storage canister of a high activity nuclear waste storage facility, using needle and steel brushes driven by pneumatic tools for abrading the bottom and the inner wall of the storage canister to remove contaminants, a multi-level filter system for air filtration and removing pollutants in the storage canister, and a cover to be used in association with the pneumatic tools and the multi-level filtration system suitable to cap the storage canister, thus effectively block the exposure of contaminant of the storage canister to the external environment, achieving effective decontamination of the radioactive waste and reducing spreading to the environment.

The group of inventions relates to constructing structures, such as the buildings of nuclear power plants, which are erected from monolithic blocks or slabs made of concrete or reinforced concrete. A block or a slab contains a built-in container with components for the sorption extraction, from water, of radionuclides or toxic substances. The container has elements for feeding-in contaminated water and for evacuating treated water. An erection method includes building a structure using the said blocks or slabs. A method for manufacturing a building block or slab includes forming a body out of concrete, embedding into same at least one container having water-treatment components, and having fittings or flanges for feeding-in contaminated water and for evacuating treated water. The invention provides for safe operations when erecting structures, and prevents the spread of radionuclides beyond the boundaries of a structure.

The group of inventions relates to constructing structures, such as the buildings of nuclear power plants, which are erected from monolithic blocks or slabs made of concrete or reinforced concrete. A block or a slab contains a built-in container with components for the sorption extraction, from water, of radionuclides or toxic substances. The container has elements for feeding-in contaminated water and for evacuating treated water. An erection method includes building a structure using the said blocks or slabs. A method for manufacturing a building block or slab includes forming a body out of concrete, embedding into same at least one container having water-treatment components, and having fittings or flanges for feeding-in contaminated water and for evacuating treated water. The invention provides for safe operations when erecting structures, and prevents the spread of radionuclides beyond the boundaries of a structure.

A decontamination paste comprising at least one inorganic viscosifier selected from clays, at least one compound in the form of fibers and optionally further one or more optional components, the remainder being of solvent. A method for decontaminating a substrate made of a solid material using the paste, the substrate being contaminated by at least one contaminant species referred to as the labile contaminant species and/or by at least one contaminant species referred to as the surface contaminant species located on one of the surfaces thereof, and/or by at least one contaminant species referred to as the subsurface contaminating species located just below said surface, and/or by at least one contaminant species located under the surface in the depth of the substrate.

A method of determining and quantifying the presence and concentration of regulated radionuclides present in filter material used to remove radionuclide contaminants from the cooling water of a nuclear reactor. Multiple samples of the reactor cooling water are taken and the presence and concentration of directly measurable fission and activation produced radionuclides are determined through gamma spectroscopy. The release rate of radioactivity from the reactor as a function of the removal rate of the filter material is determined at equilibrium. The presence and the concentration of the indirectly measured fission regulated radionuclides are determined as a function of release rates of the directly measurable fission produced isotopes.

A method of determining and quantifying the presence and concentration of regulated radionuclides present in filter material used to remove radionuclide contaminants from the cooling water of a nuclear reactor. Multiple samples of the reactor cooling water are taken and the presence and concentration of directly measurable fission and activation produced radionuclides are determined through gamma spectroscopy. The release rate of radioactivity from the reactor as a function of the removal rate of the filter material is determined at equilibrium. The presence and the concentration of the indirectly measured fission regulated radionuclides are determined as a function of release rates of the directly measurable fission produced isotopes.

This invention is directed to amorphous and crystalline titanosilicate materials that have an unexpected selectivity for cesium and strontium, especially in the presence of high levels of competing ions. The titanosilicates of this invention show very high, unexpected selectivity in the presence of such competing cations such as sodium, calcium, magnesium and potassium, such as present in seawater.