An electro-technical device includes a first housing portion electrically isolated from a second housing portion with a point source being disposed within the first housing portion. A movable conductor is connected to the first portion and is responsive to an electric field generated by the point source to cause the movable conductor to contact the second housing portion to complete a circuit and send out a control signal.

Nuclear reactor systems and methods are described having many unique features tailored to address the special conditions and needs of emerging markets. The fast neutron spectrum nuclear reactor system may include a reactor having a reactor tank. A reactor core may be located within the reactor tank. The reactor core may include a fuel column of metal or cermet fuel using liquid sodium as a heat transfer medium. A pump may circulate the liquid sodium through a heat exchanger. The system may include a balance of plant with no nuclear safety function. The reactor may be modular, and may produce approximately 100 MW .sub.e.

Nuclear reactor systems and methods are described having many unique features tailored to address the special conditions and needs of emerging markets. The fast neutron spectrum nuclear reactor system may include a reactor having a reactor tank. A reactor core may be located within the reactor tank. The reactor core may include a fuel column of metal or cermet fuel using liquid sodium as a heat transfer medium. A pump may circulate the liquid sodium through a heat exchanger. The system may include a balance of plant with no nuclear safety function. The reactor may be modular, and may produce approximately 100 MW .sub.e.

A molten salt reactor includes a containment vessel, a reactor core, a neutron reflector spaced from the containment vessel, and liquid fuel enclosed within the core. The liquid fuel is comprised of a nuclear fission material dissolved in a molten salt. A heat exchanger is positioned external to the containment vessel. A plurality of heat transfer pipes are provided for transferring heat from the core to the heat exchanger. Each pipe has a first and a second end. The first end of each pipe is positioned within the reactor core for absorbing heat from the fuel. The heat exchanger receives the second end of each heat transfer pipe. At least two or more reactor shut down systems are provided. At least one shut down system may be a passive system and at least one or both shut down systems may be an active or a manually operated system.

A control assembly for a nuclear reactor having a pump includes a duct having an inner volume and defining a coolant flow path, a plug fixed to the duct, a rod disposed within the inner volume and having a rod end that is configured to engage a neutron modifying material, a first piston disposed within the inner volume, slidably coupled to the duct, and coupled to the rod, and a biasing member coupled to the rod and the first piston. The biasing member is positioned to apply a biasing force that repositions the first piston, the rod, and the neutron modifying material in response to a loss of pump flow without scram condition.

A nuclear reactor trip apparatus includes a remote circuit breaker trip device operatively connected to a reactor trip breaker to release a control rod into a nuclear reactor core, an active power source, a passive power source, and a local circuit breaker trip device operatively connected to the reactor trip breaker including a sensor to trigger the local circuit breaker trip device upon sensing a predefined condition. The active power source is electrically coupled to energize the remote circuit breaker trip device under normal operating conditions. The passive power source is electrically coupled to energize the remote circuit breaker trip device based on a loss of the active power source.

Provided is a secondary shutdown structure of a nuclear reactor, which uses sliding doors, and more particularly, to a secondary shutdown structure of a nuclear reactor, which uses sliding doors and is capable of shutting down a nuclear reactor reliably with a simple structure without using a boric acid solution.

A molten salt reactor is described that includes a containment vessel, a reactor core housed within the containment vessel, a neutron reflector spaced from the containment vessel and positioned between the core and the containment vessel, a liquid fuel comprised of a nuclear fission material dissolved in a molten salt enclosed within the core, a plurality of heat transfer pipes, each pipe having a first and a second end, wherein the first end is positioned within the reactor core for absorbing heat from the fuel, a heat exchanger external to the containment vessel for receiving the second end of each heat transfer pipe for transferring heat from the core to the heat exchanger, and at least one and preferably two or more reactor shut down systems, where at least one may be a passive system and at least one or both may be an active or a manually operated system. The liquid fuel in the core is kept within the core and heat pipes are used to carry only the heat from the liquid core to the heat exchanger.

A passive shutdown system for a liquid metal cooled reactor may include a tube and a neutron absorber within the tube. The tube may be configured to extend through a core of the liquid metal cooled reactor. The tube has an upper end and a lower end. The tube defines a flow path for a liquid metal coolant. The neutron absorber is a mobile structure configured to partially obstruct a flow of the liquid metal coolant within the flow path. A method of operating a liquid metal cooled reactor may involve the use of the passive shutdown system.

A passive shutdown system for a liquid metal cooled reactor may include a tube and a neutron absorber within the tube. The tube may be configured to extend through a core of the liquid metal cooled reactor. The tube has an upper end and a lower end. The tube defines a flow path for a liquid metal coolant. The neutron absorber is a mobile structure configured to partially obstruct a flow of the liquid metal coolant within the flow path. A method of operating a liquid metal cooled reactor may involve the use of the passive shutdown system.