Methods and systems for stabilizing spent fuel assemblies from sodium-cooled nuclear reactors using Zamak are described herein. It has been determined that there is a synergism between Zamak and sodium that allows Zamak to form thermally-conductive interface with the sodium-wetted surfaces of the fuel assemblies. In the method, one or more spent fuel assemblies are removed from the sodium coolant pool and placed in a protective sheath. The remaining volume of the sheath is then filled with liquid Zamak. To a certain extent Zamak will dissolve and alloy with sodium remaining on the fuel assemblies. Excess sodium that remains undissolved is displaced from the sheath by the Zamak fill. The Zamak is then cooled until solid and the sheath sealed. The resulting Zamak-stabilized spent fuel assembly is calculated to have sufficient internal thermal conductivity to allow it to be stored and transported without the need for liquid cooling.

The invention relates to a technique for handling liquid radioactive waste from a nuclear fuel-energy cycle, and may be used in a process for processing liquid radioactive waste for maximally reducing the volume thereof and removing radionuclides by concentrating same in a solid phase. The aim is achieved by means of a method for processing liquid radioactive waste and for the recovery thereof, including waste oxidation, separating sludge, colloids and suspended particles from a liquid phase, and removing, from the liquid phase, radionuclides to be subsequently recovered using selective sorbents and filters; the method is characterized in that, prior to the stage for separating sludge, colloids and suspended particles from the liquid phase of the radioactive waste, selective sorbents in the form of powders are added and mixed into the liquid waste.

The invention relates to a technique for handling liquid radioactive waste from a nuclear fuel-energy cycle, and may be used in a process for processing liquid radioactive waste for maximally reducing the volume thereof and removing radionuclides by concentrating same in a solid phase. The aim is achieved by means of a method for processing liquid radioactive waste and for the recovery thereof, including waste oxidation, separating sludge, colloids and suspended particles from a liquid phase, and removing, from the liquid phase, radionuclides to be subsequently recovered using selective sorbents and filters; the method is characterized in that, prior to the stage for separating sludge, colloids and suspended particles from the liquid phase of the radioactive waste, selective sorbents in the form of powders are added and mixed into the liquid waste.

Methods and systems for stabilizing spent fuel assemblies from sodium-cooled nuclear reactors using Zamak are described herein. It has been determined that there is a synergism between Zamak and sodium that allows Zamak to form thermally-conductive interface with the sodium-wetted surfaces of the fuel assemblies. In the method, one or more spent fuel assemblies are removed from the sodium coolant pool and placed in a protective sheath. The remaining volume of the sheath is then filled with liquid Zamak. To a certain extent Zamak will dissolve and alloy with sodium remaining on the fuel assemblies. Excess sodium that remains undissolved is displaced from the sheath by the Zamak fill. The Zamak is then cooled until solid and the sheath sealed. The resulting Zamak-stabilized spent fuel assembly is calculated to have sufficient internal thermal conductivity to allow it to be stored and transported without the need for liquid cooling.

Methods and systems for stabilizing spent fuel assemblies from sodium-cooled nuclear reactors using Zamak are described herein. It has been determined that there is a synergism between Zamak and sodium that allows Zamak to form thermally-conductive interface with the sodium-wetted surfaces of the fuel assemblies. In the method, one or more spent fuel assemblies are removed from the sodium coolant pool and placed in a protective sheath. The remaining volume of the sheath is then filled with liquid Zamak. To a certain extent Zamak will dissolve and alloy with sodium remaining on the fuel assemblies. Excess sodium that remains undissolved is displaced from the sheath by the Zamak fill. The Zamak is then cooled until solid and the sheath sealed. The resulting Zamak-stabilized spent fuel assembly is calculated to have sufficient internal thermal conductivity to allow it to be stored and transported without the need for liquid cooling.

Nuclear abrasive slurry waste pump systems, devices, and methods for retrieving waste materials and/or other material from storage tanks with liquefied tank material. The systems, devices and methods can work with tanks having high temperature conditions up to approximately 212 degrees Fahrenheit or low temperature conditions down to approximately 32 degrees Fahrenheit.

Nuclear abrasive slurry waste pump systems, devices, and methods for retrieving waste materials and/or other material from storage tanks with liquefied tank material. The systems, devices and methods can work with tanks having high temperature conditions up to approximately 212 degrees Fahrenheit or low temperature conditions down to approximately 32 degrees Fahrenheit.

The invention relates to the complex processing of a nuclear power plant's NPP's liquid, boron-containing waste with a complex composition, being generated during the operation of NPPs, including of ones VVER-type, and can be used to isolate boric and nitric acids and hydroxides of sodium and potassium for their reuse in the NPP process cycle. The invention allows to obtain crystalline boric acid and highly concentrated solutions of nitric acid and hydroxides of sodium and potassium, suitable for reuse in the NPP process cycle and for general industrial use. Conducting electrodialysis at low values of current and voltage provides a reduction of the method's energy intensity. The involvement of all major components of waste mother liquors into the processing reduces the amount of stored and disposed hazardous waste.

A method includes: a pre-treatment step of mixing radiocontaminated grains and a sodium phosphate-based dispersant; and a decontamination step of mixing the radiocontaminated grains processed by the pre-treatment step and paper sludge-derived sintered carbonized porous grains so as to incorporate radioactive .sup.134Cs and .sup.137Cs of the radiocontaminated grains in the sintered carbonized porous grains.

The invention relates to the complex processing of a nuclear power plant's NPP's liquid, boron-containing waste with a complex composition, being generated during the operation of NPPs, including of ones VVER-type, and can be used to isolate boric and nitric acids and hydroxides of sodium and potassium for their reuse in the NPP process cycle. The invention allows to obtain crystalline boric acid and highly concentrated solutions of nitric acid and hydroxides of sodium and potassium, suitable for reuse in the NPP process cycle and for general industrial use. Conducting electrodialysis at low values of current and voltage provides a reduction of the method's energy intensity. The involvement of all major components of waste mother liquors into the processing reduces the amount of stored and disposed hazardous waste.