This disclosure describes various configurations and components of a molten fuel fast or thermal nuclear reactor in which one or more primary heat exchangers are located above the reactor core of the nuclear reactor.

Disclosed is a gas turbine and pressurized water reactor steam turbine combined circulation system, using a heavy duty gas turbine and a pressurized water reactor steam turbine to form a combined circulation system. Heat of the tail gas of the gas turbine is utilized to raise the temperature of a secondary circuit main steam from 272.8 C., and the temperature of the secondary circuit main steam slides between 272.8 C. and 630 C. according to different pressurized water reactor steam yields and different input numbers and loads of the heavy duty gas turbine. The system has a higher heat efficiency than that of the pressurized water reactor steam turbines in the prior art; and as for the electric quantity additionally generated by gas, the heat efficiency of the system is also significantly higher than that of gas-steam combined circulation in the prior art.

Disclosed is a gas turbine and pressurized water reactor steam turbine combined circulation system, using a heavy duty gas turbine and a pressurized water reactor steam turbine to form a combined circulation system. Heat of the tail gas of the gas turbine is utilized to raise the temperature of a secondary circuit main steam from 272.8 C., and the temperature of the secondary circuit main steam slides between 272.8 C. and 630 C. according to different pressurized water reactor steam yields and different input numbers and loads of the heavy duty gas turbine. The system has a higher heat efficiency than that of the pressurized water reactor steam turbines in the prior art; and as for the electric quantity additionally generated by gas, the heat efficiency of the system is also significantly higher than that of gas-steam combined circulation in the prior art.

Disclosed is a gas turbine and pressurized water reactor steam turbine combined circulation system, using a heavy duty gas turbine and a pressurized water reactor steam turbine to form a combined circulation system. Heat of the tail gas of the gas turbine is utilized to raise the temperature of a secondary circuit main steam from 272.8 C., and the temperature of the secondary circuit main steam slides between 272.8 C. and 630 C. according to different pressurized water reactor steam yields and different input numbers and loads of the heavy duty gas turbine. The system has a higher heat efficiency than that of the pressurized water reactor steam turbines in the prior art; and as for the electric quantity additionally generated by gas, the heat efficiency of the system is also significantly higher than that of gas-steam combined circulation in the prior art.

Disclosed is a gas turbine and pressurized water reactor steam turbine combined circulation system, using a heavy duty gas turbine and a pressurized water reactor steam turbine to form a combined circulation system. Heat of the tail gas of the gas turbine is utilized to raise the temperature of a secondary circuit main steam from 272.8 C., and the temperature of the secondary circuit main steam slides between 272.8 C. and 630 C. according to different pressurized water reactor steam yields and different input numbers and loads of the heavy duty gas turbine. The system has a higher heat efficiency than that of the pressurized water reactor steam turbines in the prior art; and as for the electric quantity additionally generated by gas, the heat efficiency of the system is also significantly higher than that of gas-steam combined circulation in the prior art.

An improved, accident tolerant fuel for use in light water and heavy water reactors is described. The fuel includes a zirconium alloy cladding having a chromium or chromium alloy coating and an optional interlayer of molybdenum, tantalum, tungsten, and niobium between the zirconium alloy cladding and the coating, and fuel pellets formed from U.sub.3Si.sub.2 or UN and from 100 to 10000 ppm of a boron-containing integral fuel burnable absorber, such as UB.sub.2 or ZrB.sub.2, either intermixed within the fuel pellet or coated over the surface of the fuel pellet.

An improved, accident tolerant fuel for use in light water and heavy water reactors is described. The fuel includes a zirconium alloy cladding having a chromium or chromium alloy coating and an optional interlayer of molybdenum, tantalum, tungsten, and niobium between the zirconium alloy cladding and the coating, and fuel pellets formed from U.sub.3Si.sub.2 or UN and from 100 to 10000 ppm of a boron-containing integral fuel burnable absorber, such as UB.sub.2 or ZrB.sub.2, either intermixed within the fuel pellet or coated over the surface of the fuel pellet.

This disclosure describes various configurations and components of a molten fuel fast or thermal nuclear reactor in which one or more primary heat exchangers are located above the reactor core of the nuclear reactor.

This disclosure describes various configurations and components of a molten fuel fast or thermal nuclear reactor in which one or more primary heat exchangers are located above the reactor core of the nuclear reactor.

An assembly is provided that includes at least one first conduit and at least one second conduit connected together through a connecting device. The connecting device includes an exteriorly threaded tube; a connecting part attached to one end of the tube and including an orifice; a holding nut screwed onto the tube and axially maintaining the connecting part relative to a tube; and a retaining member attached on the holding nut and engaging with the first conduit so as to axially retain the first conduit fitted into the orifice, the retaining member cooperating with the first conduit so as to oppose the unscrewing of the holding nut.