Cleanup systems include plural coolant inputs that are physically combined to create a single flow at a desired filtering temperature. Filter(s) are used to clean the coolant, and coolant flowing therethrough will damage the filter or not be adequately filtered if having temperature in excess of an operating temperature of the filter. The inputs have different temperatures, and mixing them creates a combined flow at a desired temperature. The amount of each flow is selected based on its individual temperature to achieve this desired temperature. The combined flow is then conditioned with the filter at an operable temperature and returned to the coolant origin for the inputs. No heat exchangers or heat loss to outside heat sinks are required. Cleanup systems may be used with any coolant loop, including Rankine-cycle electricity generation systems like nuclear power plants, combustion boilers, and steam generators, and heat transfer systems.

A filtering apparatus for a fluid intake of a nuclear power generation facility comprise primary and secondary frames. The primary frame defines an enclosed volume having least one inlet opening, and at least one outlet opening in fluid communication with the fluid intake. A primary filter is supported on the primary frame and covers the inlet opening such that fluid passes into the enclosed volume through the primary filter. The secondary frame is located within the volume enclosed by the primary frame. A secondary filter is supported on the secondary frame and defines an enclosed flow passage in communication with the outlet opening, such that fluid passes into the at least one outlet opening through the secondary filter and the enclosed flow passage.

A filtering apparatus for a fluid intake of a nuclear power generation facility comprise primary and secondary frames. The primary frame defines an enclosed volume having least one inlet opening, and at least one outlet opening in fluid communication with the fluid intake. A primary filter is supported on the primary frame and covers the inlet opening such that fluid passes into the enclosed volume through the primary filter. The secondary frame is located within the volume enclosed by the primary frame. A secondary filter is supported on the secondary frame and defines an enclosed flow passage in communication with the outlet opening, such that fluid passes into the at least one outlet opening through the secondary filter and the enclosed flow passage.

A method for at least partially disrupting or removing radioactive deposits formed on a surface of a structure in a nuclear water reactor is disclosed. The method includes identifying the structure, taking the structure out of operational service, isolating the structure, contacting the surface of the structure with an aqueous solution, and adding an effective amount of an elemental metal in solid form to the aqueous solution. The effective amount includes an amount to at least partially disrupt or remove the radioactive deposits formed on the surface of the structure. The method is conducted at ambient temperature. The radioactive deposits include oxide-containing radionuclides deposited on the surface. The surface is a primary side structure in the nuclear water reactor.

A nuclear reactor containment atmospheric filter system includes dedicated piping, valves, a control system, and a chemical injection system. An outlet of the piping can release atmospheric effluent from a reactor containment vessel into a lower portion of a spent fuel pool. The chemical injection system can release a chemical into the spent fuel pool to facilitate a reaction with the released atmospheric effluent. The reaction can assist in neutering deleterious environmental impact of the atmospheric effluent. The filter system can filter and cool contaminated air and steam vapor released from the reactor containment vessel, and prevent vessel overpressure and radioactive release.

A nuclear power plant comprising a primary coolant circuit, a steam-water circuit separated from the primary coolant circuit and a steam generator connected to the primary coolant circuit and the steam-water circuit to transfer heat from the primary coolant circuit into the steam-water circuit has at least one dosing point in the steam-water circuit to inject a reducing agent into the steam-water circuit, wherein the reducing agent is an organic compound consisting of carbon, hydrogen and oxygen. Furthermore, a method for operating said nuclear power plant and the use of the method for downtime preservation of the secondary side of a steam generator of a nuclear power plant are provided.

A nuclear power plant comprising a primary coolant circuit, a steam-water circuit separated from the primary coolant circuit and a steam generator connected to the primary coolant circuit and the steam-water circuit to transfer heat from the primary coolant circuit into the steam-water circuit has at least one dosing point in the steam-water circuit to inject a reducing agent into the steam-water circuit, wherein the reducing agent is an organic compound consisting of carbon, hydrogen and oxygen. Furthermore, a method for operating said nuclear power plant and the use of the method for downtime preservation of the secondary side of a steam generator of a nuclear power plant are provided.

A nuclear containment atmospheric filter including dedicated piping, valves, a control system and a chemical injection system to facilitate the use of a commercial nuclear power plant's Spent Fuel Storage Pool and Spent Fuel Storage Pool Cooling System to filter and cool contaminated air and steam vapor released from within a Reactor Containment Vessel/Building preventing vessel overpressure and radioactive release.

Some embodiments include a method comprising: flowing a molten salt out of a molten salt reactor at a first temperature, heating the molten salt reactor to a second temperature above the melding point of the second salt mixture causing the second salt mixture to melt; flowing the second salt mixture out of the molten salt reactor; flowing a third salt mixture into the molten salt reactor; and cooling the molten salt reactor from the second temperature to a third temperature causing the third salt mixture to solidify on the interior surface of the housing. In some embodiments, the molten salt may include a first salt mixture comprising at least uranium. In some embodiments, the first temperature is a temperature above the melting point of the first salt mixture.

A method and apparatus for improved separation and containment of radioactive particulates from liquids by filtration. The improvements are achieved by utilizing more than one stage of filtration to remove radioactive particulates from a fluid. The first stage of filtration is designed for high liquid flowrate, low differential pressure across the filter medium, and reversibility of flow through the medium to facilitate backwashing. The second or more stages of filtration receive the backwash flow and captured particulates from the first stage at a lower flowrate, but at high pressure using a high-pressure pump configured between the stages.