Abstract: The present disclosure relates to a passive safety system which uses a heat exchanger together with a thermoelectric element, and a nuclear power plant comprising the same. Disclosed are a passive safety system and a nuclear power plant comprising the same, the passive safety system comprising: a heat exchanger; a thermoelectric element; and a fan unit. The heat exchanger is formed at a space inside or outside a sealed housing, and in the heat exchanger, atmosphere is introduced and heat exchange is carried out in order to lower the pressure or temperature of the atmosphere inside the housing if an accident occurs in a reactor coolant system or a secondary system disposed inside the housing.

Abstract: The present disclosure may disclose a multi stage safety injection device and a passive safety injection system having the same, including a safety injection tank formed to contain coolant to be injected into a reactor vessel by a gravitational head of water when an accident occurs in which the pressure or water level of the reactor vessel is decreased, a pressure balance line connected to the reactor vessel and safety injection tank to form a pressure balance state between the reactor vessel and the safety injection tank, a safety injection line connected to a lower end portion of the safety injection tank and the reactor vessel to inject coolant to the reactor vessel in a pressure balance state between the reactor vessel and the safety injection tank, and a flow control line extended from the safety injection line to an inner portion of the safety injection tank, and provided with safety injection ports into which coolant is injected at predetermined heights, respectively, to reduce the flow rate of coolant

Abstract: The present invention relates to a passive heat removal system which circulates cooling fluid via a main water supply line, connected to the lower inlet of a steam generator, and a main steam pipe, connected to the top outlet of the steam generator, to the steam generator, in order to remove sensible heat of a reactor coolant system and residual heat of a core, the passive heat removal system comprising: supplementary equipment for receiving surplus cooling fluid or supplying supplementary cooling fluid in order to maintain the flow rate of the cooling fluid within a predetermined range, wherein the supplementary equipment comprises: a supplementary tank, installed at a predetermined height between the lower inlet and the top outlet of the steam generator, for receiving the surplus cooling fluid or supplying the supplementary cooling fluid, passively, depending on the flow rate of the cooling fluid; a first connection pipe, connected to the main steam pipe and the supplementary tank, for forming a flow path t

Abstract: A passive safety system includes a containment, a reactor in the containment, a plurality of safety injection tanks connected with the reactor and having water and nitrogen gas to supply water thereof into the reactor through a safety injection line communicating to the first safety injection line upon a loss of coolant accident, a plurality of core makeup tanks connected with the reactor to supply water thereof into the reactor through a second safety injection line communicating to a safety injection line upon the loss of coolant accident, and a plurality of passive residual heat removal systems to remove residual heat from the reactor upon the loss of coolant accident or a non-loss of coolant accident. The water in each of the safety injection tank is stably supplied to the reactor for many hours by a differential head resulting from gravity or gas pressure.

Abstract: The present invention discloses a passive cooling system of a containment building, to which a plate-type heat exchanger is applied. A passive cooling system of a containment building comprises: a containment building; a plate-type heat exchanger provided to at least one of the inside and the outside of the containment building and comprising channels respectively provided to the both sides of a plate so as to be arranged dividedly from each other such that the plate-type heat exchanger carries out mutual heat exchange between the internal atmosphere of the containment building and a heat exchange fluid while maintaining a pressure boundary; and a pipe connected to the plate-type heat exchanger by penetrating the containment building so as to form the path of the internal atmosphere of the containment building or the heat exchange fluid.

Abstract: The present invention provides a passive residual heat removal system and an atomic power plant comprising the same, the passive heat removal system comprising: a plate-type heat exchanger for causing heat exchange between a primary system fluid or a secondary system fluid which, in order to remove sensible heat from an atomic reactor cooling material system and residual heat from a reactor core, has received the sensible heat and the residual heat, and a cooling fluid which has been introduced from outside of a containment unit; and circulation piping for connecting the atomic reactor cooling material system to the plate-type heat exchanger, thereby forming a circulation channel of the primary system fluid, or connecting a steam generator, which is arranged at the boundary between the primary and secondary systems, to the plate-type heat exchanger, thereby forming a circulation channel of the secondary system fluid.

Abstract: The present invention discloses a nuclear reactor coolant pump that does not rely on an electric motor, but is operated by means of driving force generated inside a nuclear power plant, so a to be capable of maintaining the safety of the nuclear reactor when the nuclear reactor is operating normally and also in the event of an accident in the nuclear reactor. The nuclear reactor coolant pump comprises: a pump impeller rotatably installed in a first fluid passage of a nuclear reactor coolant system to circulate a first fluid inside the nuclear reactor coolant system; a drive unit receiving steam from a steam generator to generate driving force to rotate the pump impeller, and rotating about the same rotating shaft as the pump impeller to transfer the generated driving force to the pump impeller; and a steam supplying unit forming a passage between the steam generator and the drive unit to supply at least a portion of the steam released from the steam generator to the drive unit.

Abstract: The present invention provides passive safety equipment, comprising: a cooling part formed to cool a first fluid, which is emitted from a reactor coolant system or a steam generator, and a second fluid in a housing; and a circulation induction sprayer which is formed to spray the first fluid emitted from the reactor coolant system or the steam generator into the cooling part, has at least part thereof open to the inside of the housing such that the second fluid flows thereinto according to a drop in pressure caused by the spraying of the first fluid, and sprays the second fluid with the inflown first fluid.

Abstract: A magnetostrictive wire control rod position indicator for determining a real-time position of a control rod using a mutual interference effect between a magnetic field formed by supplying a pulse current to a magnetostrictive wire provided inside a protecting tube and a magnetic field formed by a permanent magnet of a drive shaft includes magnet members installed at an upper limit position and a lower limit position of the magnetostrictive wire control rod position indicator to cause magnetic field interference with the permanent magnet of the drive shaft.

Abstract: Disclosed is a heat exchanger for a passive residual heat removal system, which improves heat transfer efficiency by expanding a heat transfer area. A heat exchange tube includes a first member connected to a steam pipe through which steam generated from a steam generator of a nuclear reactor circulates, and a second member connected to both of the first member and a feed water pipe used to supply water to the steam generator provided in the nuclear reactor, and the first member has the shape different from that of the second member, thereby expanding the heat transfer area so that the heat transfer efficiency is improved.

Abstract: The present invention provides a facility for reducing radioactive material comprising: a cooling water storage unit installed inside a containment and formed to store cooling water; a boundary unit forming a boundary of radioactive material inside the containment and surrounding a reactor coolant system installed inside the containment to prevent a radioactive material from releasing from the reactor coolant system or a pipe connected with the reactor coolant system to the containment; a connecting pipe connected with an inner space of the boundary unit and the cooling water storage unit to guide a flow of a fluid caused by a pressure difference between the boundary unit and the cooling water storage unit from the boundary unit to the cooling water storage unit; and a sparging unit disposed to be submerged in the cooling water stored in the cooling water storage unit and connected with the connecting pipe to sparge the fluid that has passed through the connecting pipe and the radioactive material contained i

Abstract: Disclosed are an in-vessel control rod drive mechanism and a nuclear reactor with the same. The in-vessel control rod drive mechanism includes a control rod drive mechanism for regulating and a control rod drive mechanism for shutdown provided at an upper or lower space of a reactor core to insert or withdraw a regulating rod and a shutdown rod into/from the reactor core based on an operation state of the nuclear reactor, wherein the control rod drive mechanism for regulating and the control rod drive mechanism for shutdown are alternately arranged in the vertical direction. Therefore, a space of containment can be minimized due to the installation of the in-vessel control rod drive mechanism, and thus a rod ejection accident can be prevented, and a loss-of-coolant accident can be reduced.

Abstract: Disclosed is a control rod drive mechanism. More specifically, the control rod drive mechanism includes a guide member 100 disposed in a nuclear reactor to receiving a drive shaft 2; a latch assembly 200 disposed in the guide member 100 to enable the drive shaft 2 to be withdrawn and inserted; a supporting member 300 connected to the guide member 100 to cover the drive shaft 2 and to support the latch assembly 200; and a plurality of coil housings 400 spaced apart and connected to the guide member 100 to cover the latch assembly 200, and each having a coil 410 built therein.

Abstract: Provided is a passive containment spray system including: a spray coolant storage unit that communicates with a containment accommodating a reactor vessel and maintains equilibrium of pressure between the spray coolant storage unit and the containment; a spray pipe that is installed within the containment in such a manner that when an accident occurs, a coolant supplied from the spray coolant storage unit is sprayed into the containment through the spray pipe due to an increase in pressure within the containment; and a connection pipe one end of which is inserted into the spray coolant storage unit in such a manner as to provide a flow path along which the coolant flows and the other end of which is connected to the spray pipe in such a manner that the coolant is passively supplied to the spray pipe through the connection pipe therein.

Abstract: The present disclosure provides a cooling system of an emergency cooling tank, which enables long-term cooling without refilling cooling water, in case of the change in a quantity of heat transferred to the emergency cooling tank according to a lapse of time upon an occurrence of an accident of a nuclear reactor, and a nuclear power plant having the same.

Abstract: The present disclosure may disclose a multi stage safety injection device and a passive safety injection system having the same, including a safety injection tank formed to contain coolant to be injected into a reactor vessel by a gravitational head of water when an accident occurs in which the pressure or water level of the reactor vessel is decreased, a pressure balance line connected to the reactor vessel and safety injection tank to form a pressure balance state between the reactor vessel and the safety injection tank, a safety injection line connected to a lower end portion of the safety injection tank and the reactor vessel to inject coolant to the reactor vessel in a pressure balance state between the reactor vessel and the safety injection tank, and a flow control line extended from the safety injection line to an inner portion of the safety injection tank, and provided with safety injection ports into which coolant is injected at predetermined heights, respectively, to reduce the flow rate of coolant

Abstract: The present disclosure may disclose a multi stage safety injection device, including a safety injection tank formed to contain coolant to be injected into a reactor vessel by a gravitational head of water when an accident occurs in which the pressure or water level of the reactor vessel is decreased, a pressure balance line connected to the reactor vessel and safety injection tank to form a pressure balance between the reactor vessel and the safety injection tank, and a set of safety injection lines connected to the safety injection tank and the reactor vessel to inject coolant to the reactor vessel in a pressure balance state between the reactor vessel and the safety injection tank, and connected to the safety injection tank with different heights to reduce a flow rate of coolant injected into the reactor vessel step by step according to the water level reduction of the safety injection tank in order to inject coolant to the reactor vessel at multi stages.

Abstract: A separate type safety injection tank comprises: a coolant injection unit connected to a reactor coolant system by a safety injection pipe such that coolant stored therein is injected into the reactor coolant system by a pressure difference from the reactor coolant system when a loss-of-coolant-accident (LOCA) occurs; a gas injection unit connected to the coolant injection unit, and configured to pressurize the coolant injected into the reactor coolant system, by introducing gas stored therein to an upper part of the coolant injection unit in the loss-of-coolant-accident; and a choking device disposed between the coolant injection unit and the gas injection unit, and configured to contract a flow cross-sectional area of the gas introduced to the coolant injection unit, and configured to maintain a flow velocity and a flow rate of the gas introduced to the coolant injection unit as a critical flow velocity and a critical flow rate when a pressure difference between the coolant injection unit and the gas inject

Abstract: A passive safety system includes a containment, a reactor in the containment, a plurality of safety injection tanks connected with the reactor and having water and nitrogen gas to supply water thereof into the reactor through a safety injection line communicating to the first safety injection line upon a loss of coolant accident, a plurality of core makeup tanks connected with the reactor to supply water thereof into the reactor through a second safety injection line communicating to a safety injection line upon the loss of coolant accident, and a plurality of passive residual heat removal systems to remove residual heat from the reactor upon the loss of coolant accident or a non-loss of coolant accident. The water in each of the safety injection tank is stably supplied to the reactor for many hours by a differential head resulting from gravity or gas pressure.

Abstract: A passive safety injection system includes a containment, a reactor installed in the containment, safety injection tanks installed in the containment, a safety injection line between the reactor or a reactor coolant system and each of the safety injection tanks to guide water, which is stored in the safety injection tank, into the reactor when a water level in the reactor is reduced due to a loss of coolant accident, and a pressure balance line between the reactor or the reactor coolant system and the safety injection tank to guide high-temperature steam from the reactor into the safety injection tank upon the loss of coolant accident. The safety injection line has an orifice and a check valve thereon, and the pressure balance line has an orifice and isolation valves thereon. The water in the safety injection tank stably flows into the reactor for many hours.