An organic Rankine cycle machine and a supplementary reservoir of water, distinct from the pool, the energy stored in the pool being the hot source for the organic Rankine cycle evaporator, the supplementary reservoir of water feeding the organic Rankine cycle condenser directly via a dedicated pump to constitute the cold source of the organic Rankine cycle condenser.

The invention relates to nuclear power engineering and is designed to improve the safety of nuclear power plants by providing the ability to retain the melt in the nuclear reactor vessel at different severity of accidents in both passive and active mode.

In-vessel melt retention system containing a reactor located in a cavity, a coolant circulation pump outside the reactor vessel and a storage tank, characterized in that the storage tank is located in the cavity under the reactor vessel head; there are additional sump tanks above the reactor vessel head to collect coolant in LOCAs, the storage tank is connected to the top of the sump tanks by coolant supply channels.

The in-vessel melt retention system can be applied in nuclear power plants of various types, and can increase their safety by providing melt retention in the reactor vessel in various types of accidents.

The method and system for bringing a nuclear power plant to a safe state after extreme effect reduce the temperature of the coolant after extreme effect. The system includes inlet and outlet pipelines, a steam generator, a storage tank and a heat exchanger, a separation tank above the steam generator and connected by two pipelines to a storage tank, a pump, a control unit. The method involves filling the system with coolant, feeding the coolant from the steam generator through the inlet pipeline and the storage tank to the heat exchanger, and feeding the coolant through the outlet pipeline back to the steam generator, wherein the pump is turned on for feeding the coolant and subsequent operation of the system. The first air valve is used to maintain pressure in the system, ensuring the absence of boiling of the coolant.

Passive safety systems cool reactors using surrounding ground as a heat sink. A coolant flow channel may loop around the reactor and then pass outside, potentially through a containment building, into surrounding ground. No active components need be used in example embodiment safety systems, which may be driven entirely by gravity-based natural circulation. The coolant loop may be air-tight and seismically-hardened and filled with any coolant such as water, air, nitrogen, a noble gas, a refrigerant, etc. The ground may include a soil of grey limestone, soft grey fine sandy clay, grey slightly silty sandy gravel, etc. or any other fill with desired heat-transfer characteristics. Coolant fins and/or jackets with secondary coolants may be used on the coolant loop. The coolant loop may be buried at any constant or variable depth, and the reactor and containment may also be buried in the ground.

Disclosed herein is a reactor including a reactor vessel and a containment vessel configured to surround the reactor vessel. The containment vessel includes a thermal radiation shield disposed on an inner wall, and a gap between the reactor vessel and the containment vessel is in an atmospheric pressure and air atmosphere state.

A nuclear reactor cooled by liquid metal incorporating a passive system for evacuation of the decay heat with a phase change material thermal reservoir and a removable thermally-insulating layer around the phase change material reservoir. A nuclear reactor incorporates an integral system that guarantees: totally passive evacuation of decay heat from the initial moment of the accident; evacuation of power via the primary containment vessel; the presence of a final cold source with a reservoir incorporating an integral exchanger divided into a plurality of parallel tubes between which a phase change material is inserted, the reservoir being surrounded by a thermally-insulating layer that can be detached in a passive manner in the event of reaching a predetermined threshold temperature.

In conjunction with a pressurized water reactor (PWR) and a pressurizer configured to control pressure in the reactor pressure vessel, a decay heat removal system comprises a pressurized passive condenser, a turbine-driven pump connected to suction water from at least one water source into the reactor pressure vessel; and steam piping configured to deliver steam from the pressurizer to the turbine to operate the pump and to discharge the delivered steam into the pressurized passive condenser. The pump and turbine may be mounted on a common shaft via which the turbine drives the pump. The at least one water source may include a refueling water storage tank (RWST) and/or the pressurized passive condenser. A pressurizer power operated relief valve may control discharge of a portion of the delivered steam bypassing the turbine into the pressurized passive condenser to control pressure in the pressurizer.

A nuclear reactor includes an internal steam generator and a nuclear core disposed in a containment structure. A condenser is disposed outside the containment structure, and includes a condenser inlet line tapping off a steam line connected to the steam generator outside the containment structure, and a condensate injection line conveying condensate from the condenser to the integral steam generator. Isolation valves are located outside the containment structure on a feedwater line, the steam line, and the condensate injection line. The valves have an operating configuration in which the isolation valves on the feedwater and steam lines are open and the isolation valve on the condensate injection line is closed, and a heat removal configuration in which the isolation valves on the feedwater and steam lines are closed and the isolation valve on the condensate injection line is open.

An in-vessel cooling and power generation system according to the present disclosure may include a small scale reactor vessel, a heat exchange section provided inside the reactor vessel, and formed to supply supercritical fluid to receive heat from a reactor coolant system in the reactor vessel, an electric power production section comprising a supercritical turbine formed to produce electric energy using the energy of the supercritical fluid whose temperature has increased while receiving heat from the reactor coolant system, a cooling section configured to exchange heat with the supercritical fluid discharged after driving the supercritical turbine to shrink a volume of the supercritical fluid, wherein the supercritical fluid that has received heat from the reactor coolant system in the heat exchange section is formed to circulate through the electric power production section, and the cooling section.

A method of providing an emergency supply of services to a nuclear power plant having a cooling water cycle, the method including: situating a container at a remote location from the power plant, wherein the container has permanently integrated therein: a motor comprising a first shaft and a second shaft; a generator driven by the first shaft; a pump driven by the second shaft; a fuel tank connected to the motor, and supplying fuel to the motor; and a transformer connected to the generator; connecting the pump to the cooling water cycle of the nuclear power plant; using the pump to pump water from an external water feed into the cooling water cycle of the nuclear power plant.