Mobile apparatuses move within contaminated fluid to create fluid flows against structures that remove and prevent contaminant deposition on structure surfaces immersed in the fluid. Unsettling flows in water may exceed approximately 2 m/s for radionuclide particles and solutes found in nuclear power plants. Mobile apparatuses include pressurized liquid from a pump or pressurized source that can be chemically and thermally treated to maximize deposition removal. When spraying the pressurized liquid to create the deposition-removing flow, mobile apparatuses may be self-propelled within the fluid about an entire surface to be cleaned. Mobile apparatuses include filters keyed to remove the contaminants moved into the coolant by the flow, and by taking in ambient fluid, enable such filtering of the ambient fluid along with a larger flow volume and propulsion. Propulsion and the pressurized liquid in turn enhance intake of ambient fluid.

A turbine includes a central hub to rotate around an axis and a plurality of blades connected to the central hub. Each blade of the set of blades includes a support material having an exterior facing surface and a ceramic nitride coating disposed over the exterior facing surface. The ceramic nitride coating includes a semi-metal nitride, such as silicon nitride. The ceramic nitride coating can have a thickness in a range of 50 nm to 5 micrometers. A rough material layer can be disposed between the support material and the ceramic nitride coating.

A film forming apparatus is connected to a carbon steel purification system piping of a BWR plant (S1). Formic acid (surface purification agent) is injected into a circulation piping of the film forming apparatus (S4). A surface purification agent aqueous solution containing 30000 ppm of formic acid is contacted with the inner surface of the purification system piping, and a large amount of Fe.sup.2+ is dissolved from the purification system piping, and a large amount of electrons are generated by this dissolution. Thereafter, a formic acid Ni aqueous solution is injected into the surface purification agent aqueous solution to produce a film forming aqueous solution (S5). The film forming aqueous solution storing the electrons is contacted with the inner surface of the purification system piping, and Ni ions incorporated into the inner surface are reduced by the electrons, and a Ni metal film is formed on the inner surface. Platinum ions and a reducing agent are injected into the circulation piping (S9, S10), and an aqueous solution containing the platinum ions and the reducing agent is supplied to the purification system piping to deposit platinum on the surface of the Ni metal film.

A rotary device for a nuclear power facility, the rotary device being placed in a circuit for coolant containing radioactive nuclides in the nuclear power facility. The rotary device includes: a casing; and a rotary mechanism provided with, in the casing, a rotor and a rotor shaft that come into contact with the coolant containing the radioactive nuclides passing through the casing. Regarding the casing and the rotary mechanism, at least the rotor and the rotor shaft of the rotary mechanism comprise a low-effective diffusion coefficient alloy having a lower effective diffusion coefficient than a polycrystalline alloy.

An insulated solution injector may include an outer tube and an inner tube arranged within the outer tube. The outer tube and the inner tube may define an annular space therebetween, and the inner tube may define a solution space within. The annular space may be configured so as to insulate the solution within the solution space. As a result, the solution may be kept to a temperature below its decomposition temperature prior to injection. Accordingly, the decomposition of the solution and the resulting deposition of its constituents within the solution space may be reduced or prevented, thereby decreasing or precluding the occurrence of a blockage.

Methods and systems for removing impurities from a molten salt stream are provided. A molten salt stream is provided that comprises a mixture of compounds selected from the group consisting of LiF, BeF.sub.2, and NaF, and ZrF.sub.4. The molten salt stream is flowed through a loop that may contain a precipitation filter, electrochemical potential, and/or a sparger, which thereby remove impurities in the molten salt stream. Various physical methods and apparatus are used to control the ability to remove impurities from the molten salt stream based on temperature, solubility, and general chemistry control.

A device adapted for producing energy by nuclear fission, the device comprising a core container of a core container material, which core container encloses an inner tubing of an inner tubing material, the inner tubing and/or the core container having an inlet and an outlet, the device further comprising a molten fuel salt with a fissionable material and a molten moderator salt comprising at least one metal hydroxide, at least one metal deuteroxide or a combination thereof and a redox-element having a reduction potential, which is larger than that of the inner tubing material or of the inner tubing material and the core container material, wherein the molten moderator salt is located in the core container and the molten fuel salt is located in the inner tubing, or wherein the molten fuel salt is located in the core container and the molten moderator salt is located in the inner tubing. The invention also relates to methods of controlling nuclear fission processes using the device and to the use of a molten salt comprising at least one metal hydroxide, at least one metal deuteroxide or a combination thereof and a redox-element for moderating fission neutrons created in a fission reaction process.

The present disclosure provides a method for relieving a corrosive environment of a boiling water reactor, the method including a step of injecting hydrogen and a noble metal compound into water to be replenished into the reactor pressure vessel during a period of a generating operation of a boiling water nuclear power plant including the reactor pressure vessel. In the method, the hydrogen is injected into water to be supplied into the reactor pressure vessel, and the noble metal compound is injected into water in a line of the boiling water nuclear power plant in which a concentration of oxygen or hydrogen peroxide is stoichiometrically higher than the concentration of hydrogen at which hydrogen undergoes a chemical reaction to turn to water. Thus, when a noble metal is injected into a boiling water reactor, the noble metal can be restrained from adhering onto a pipe for an injection and other pipes, and thereby can increase the amount of the noble metal to be injected into a cooling water in a reactor pressure vessel.

A system for injecting hydrogen into Boiling Water Reactor (BWR) reactor support systems in operation during reactor startup and/or shutdown. The system the hydrogen injection system includes at least one hydrogen source, flow control equipment, and pressure control equipment. The pressure control equipment being configured to regulate a pressure of a hydrogen flow between the at least one hydrogen source and the at least one first BWR support system based upon an operating pressure of the at least one first BWR support system.

Disclosed are an apparatus and a method for purifying reactor coolant radioactive material and adjusting the pH of the reactor coolant, to replace and overcome the disadvantages of the purification and Li adjustment of a reactor coolant, by conventional ion-exchange resins; to concentrate, store and reuse Li.sup.7, which is naturally produced in a nuclear reactor during power operation, without injecting expensive LiOH obtained by removing Li.sup.6 and concentrating only Li.sup.7; or to solve the problem that lithium (Li.sup.+) ions used as a pH adjusting agent are removed together with radioactive metal ion materials which is and adverse effect occurring when the lithium ions are applied to a reactor coolant purification apparatus.