An anti-proliferation technique is disclosed to reduce the likelihood of nuclear proliferation due to the use fissionable fuel salts. The technique includes doping the fuel salt with one or more elements (referred to herein as activation dopants) that, upon exposure to neutrons such as would occur in the fuel salt when a reactor is in operation, undergo a nuclear reaction to, directly or indirectly, form highly active protecting isotopes (of the same element as the activation dopant or a different element). A sufficient mass of activation dopants is used so that the Figure of Merit (FOM) of the fuel salt is decreased to below 1.0 within some target number of days of fission. This allows the FOM of the fuel salt to be controlled so that the fuel becomes too dangerous to handle before to the creation of a significant amount of weaponizable isotopes.

A system and method for drying cavities containing spent nuclear fuel is devised. The invention utilizes a non-intrusive procedure that is based on monitoring the dew point temperature of a non-reactive gas that is circulated through the cavity. In one aspect, the invention is a system for drying a cavity loaded with spent nuclear fuel comprising a canister forming the cavity, the cavity having an inlet and an outlet; a source of non-reactive gas; means for flowing the non-reactive gas from the source of non-reactive gas through the cavity; and means for repetitively measuring the dew point temperature of the non-reactive gas exiting the cavity.

Apparatuses for reducing or eliminating Type 1 LOCAs in a nuclear reactor vessel. A nuclear reactor including a nuclear reactor core comprising a fissile material, a pressure vessel containing the nuclear reactor core immersed in primary coolant disposed in the pressure vessel, and an isolation valve assembly including, an isolation valve vessel having a single open end with a flange, a spool piece having a first flange secured to a wall of the pressure vessel and a second flange secured to the flange of the isolation valve vessel, a fluid flow line passing through the spool piece to conduct fluid flow into or out of the first flange wherein a portion of the fluid flow line is disposed in the isolation valve vessel, and at least one valve disposed in the isolation valve vessel and operatively connected with the fluid flow line.

Apparatuses for reducing or eliminating Type 1 LOCAs in a nuclear reactor vessel. A nuclear reactor including a nuclear reactor core comprising a fissile material, a pressure vessel containing the nuclear reactor core immersed in primary coolant disposed in the pressure vessel, and an isolation valve assembly including, an isolation valve vessel having a single open end with a flange, a spool piece having a first flange secured to a wall of the pressure vessel and a second flange secured to the flange of the isolation valve vessel, a fluid flow line passing through the spool piece to conduct fluid flow into or out of the first flange wherein a portion of the fluid flow line is disposed in the isolation valve vessel, and at least one valve disposed in the isolation valve vessel and operatively connected with the fluid flow line.

A molten salt reactor system may produce fission products, such as molybdenum-99, which may be extracted by an extraction system. The extraction system may be configured to sparge the molten fuel salt with an inert gas to dislodge gaseous fission products from the molten fuel salt, so that the gaseous fission products flow through an off-gas outlet into a gas transfer assembly. The example extraction system may also include introducing a gaseous halogenating agent to prevent the fission products from depositing on a pipe surface of the gas transfer assembly. The gaseous fission products may flow from the gas transfer assembly to a carboy containing an aqueous solution, to process and/or filter the fission products. The resulting solution containing processed fission products in the carboy may be further distilled into final, usable products.

A molten salt reactor system may produce fission products, such as molybdenum-99, which may be extracted by an extraction system. The extraction system may be configured to sparge the molten fuel salt with an inert gas to dislodge gaseous fission products from the molten fuel salt, so that the gaseous fission products flow through an off-gas outlet into a gas transfer assembly. The example extraction system may also include introducing a gaseous halogenating agent to prevent the fission products from depositing on a pipe surface of the gas transfer assembly. The gaseous fission products may flow from the gas transfer assembly to a carboy containing an aqueous solution, to process and/or filter the fission products. The resulting solution containing processed fission products in the carboy may be further distilled into final, usable products.

A molten salt reactor system may produce fission products, such as molybdenum-99, which may be extracted by an extraction system. The extraction system may be configured to sparge the molten fuel salt with an inert gas to dislodge gaseous fission products from the molten fuel salt, so that the gaseous fission products flow through an off-gas outlet into a gas transfer assembly. The example extraction system may also include introducing a gaseous halogenating agent to prevent the fission products from depositing on a pipe surface of the gas transfer assembly. The gaseous fission products may flow from the gas transfer assembly to a carboy containing an aqueous solution, to process and/or filter the fission products. The resulting solution containing processed fission products in the carboy may be further distilled into final, usable products.

A debris filter bottom nozzle for a nuclear reactor fuel assembly. The nozzle comprising venturi-shaped flow passages within a plate body. At least one flow passage has a filter therein, with the uppermost and lowermost ends of the filter being situated between the upper and lower ends of the flow passage. The plate body, the flow passages, and each filter are co-formed as a single piece unitary body. The co-forming may be via additive manufacturing.