摘要:
A method of forming an oxide coating for reducing the accumulation of radioactive species on a metallic surface exposed to fluids containing charged particles is disclosed. The method includes preparing an aqueous colloidal suspension containing about 0.5 to about 35 weight percent of nanoparticles that contain at least one of titania and zirconia, and about 0.1% to about 10% 2-[2-(2-methoxyethoxy)ethoxy]acetic acid (C7H14O5) or polyfluorosufonic acid in water, depositing the aqueous colloidal suspension on the metallic surface, drying the aqueous colloidal suspension to form a green coating, and then heating the green coating to a temperature of up to 500° C. to densify the green coating to form an oxide coating having a zeta potential less than or equal to the electrical polarity of the charged particles so as to minimize deposition of the charged particles on the metallic surface. The nanoparticles have a diameter of up to about 200 nanometers.
摘要:
Provided is a replacement basket configured to house a pellet bed through which fluid may pass. The flow direction of the fluid prevents the bed of pellets from fluidizing within the replacement basket. Provided also is a system using the replacement basket and a method of providing pellets in the replacement basket. According to example embodiments, a replacement basket may include a top surface portion, a bottom, and at least one vertical wall with a hole. The hole is configured to allow a flow of fluid to enter the replacement basket. A plenum, below the pellet bed, may allow a flow of fluid to proceed through the pellet bed in a downward direction. A central pipe may be provided in the replacement basket to allow the flow of fluid in the basket to exit the replacement basket.
摘要:
In a method of monitoring deposition of a noble metal in an intergranular stress corrosion crack (IGSCC) in a metal reactor shroud wall of a nuclear reactor, a metal sample may be placed at a location within near an inner surface of the metal reactor shroud wall. The sample may be submerged below a water line in the reactor and includes at least one thermal fatigue crack. The sample is maintained at the location for a given duration, and a given amount of the noble metal is added into the reactor water while the sample is maintained at the location. The sample is then removed. In an example, a surface crevice deposition monitor for a reactor includes a flow conditioner arranged between a securing mechanism and an anchor, and at least one sample holder connected between the securing mechanism and flow conditioner.
摘要:
In a method of monitoring deposition of a noble metal in an intergranular stress corrosion crack (IGSCC) in a metal reactor shroud wall of a nuclear reactor, a metal sample may be placed at a location within near an inner surface of the metal reactor shroud wall. The sample may be submerged below a water line in the reactor and includes at least one thermal fatigue crack. The sample is maintained at the location for a given duration, and a given amount of the noble metal is added into the reactor water while the sample is maintained at the location. The sample is then removed. In an example, a surface crevice deposition monitor for a reactor includes a flow conditioner arranged between a top guide clamp and an anchor clamp, and at least one sample holder connected between the top guide clamp and flow conditioner.
摘要:
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.
摘要:
Provided is a replacement basket configured to house a pellet bed through which fluid may pass. The flow direction of the fluid prevents the bed of pellets from fluidizing within the replacement basket. Provided also is a system using the replacement basket and a method of providing pellets in the replacement basket. According to example embodiments, a replacement basket may include a top surface portion, a bottom, and at least one vertical wall with a hole. The hole is configured to allow a flow of fluid to enter the replacement basket. A plenum, below the pellet bed, may allow a flow of fluid to proceed through the pellet bed in a downward direction. A central pipe may be provided in the replacement basket to allow the flow of fluid in the basket to exit the replacement basket.
摘要:
In a method of monitoring deposition of a noble metal in an intergranular stress corrosion crack (IGSCC) in a metal reactor shroud wall of a nuclear reactor, a metal sample may be placed at a location within near an inner surface of the metal reactor shroud wall. The sample may be submerged below a water line in the reactor and includes at least one thermal fatigue crack. The sample is maintained at the location for a given duration, and a given amount of the noble metal is added into the reactor water while the sample is maintained at the location. The sample is then removed. In an example, a surface crevice deposition monitor for a reactor includes a flow conditioner arranged between a top guide clamp and an anchor clamp, and at least one sample holder connected between the top guide clamp and flow conditioner.
摘要:
An apparatus for carrying out a surveillance program to monitor the neutron fluence and its effect on vessel materials at a position in the annular space between the pressure vessel and core shroud of a boiling water reactor for the purpose of monitoring vessel embrittlement. The apparatus includes an offset capsule holder assembly which fits in an existing capsule holder attached to the inner surface of the pressure vessel wall. The offset capsule holder assembly positions a new capsule holder radially closer to the core, by an amount determined by neutron transport calculations. The new capsule holder is geometrically identical to the original, or a "replacement in kind", allowing the original surveillance capsules to be immediately reinstalled. With the water moderator in the downcomer annulus, the fluence rate increases significantly when the surveillance capsule is moved radially inward from the pressure vessel inside surface toward the core.