Abstract: Provided is a combustion controller for a combustible gas of a pressurized water reactor nuclear power plant, and more particularly, to a combustion controller for a combustible gas installed in a rear end of a filtered vent system outside a containment vessel or an external chimney, configured to convert a combustible gas such as hydrogen, carbon monoxide, or the like, into steam, carbon dioxide, or the like, and simultaneously, operate by itself with no external power supply. Accordingly, the combustion controller for a combustible gas can perform stable combustion control with no probability of explosion of hydrogen through a recombining reaction of the combustible gas, prevent discharge of carbon monoxide, which is a toxic gas, and prevent backward flow of the flame through the quenching mesh.

Abstract: A nuclear power plant includes a nuclear reactor containment structure housing a nuclear reactor, a pressure vessel containing condensed water therein and having a receiving space located lower than a bottom of the containment structure, a release pipe connecting the containment structure to the pressure vessel such that water vapor and fission products generated in the containment structure in the event of an accident is capable of flowing into the pressure vessel, and a recovery pipe connecting the pressure vessel to the containment structure such that the condensed water received in the pressure vessel is capable of flowing into the containment structure. When a level of the condensed water received in the pressure vessel is higher than a water level in the containment structure, the condensed water flows from the pressure vessel toward the containment structure by a water head difference.

Abstract: Provided is a combustion controller for a combustible gas of a pressurized water reactor nuclear power plant, and more particularly, to a combustion controller for a combustible gas installed in a rear end of a filtered vent system outside a containment vessel or an external chimney, configured to convert a combustible gas such as hydrogen, carbon monoxide, or the like, into steam, carbon dioxide, or the like, and simultaneously, operate by itself with no external power supply. Accordingly, the combustion controller for a combustible gas can perform stable combustion control with no probability of explosion of hydrogen through a recombining reaction of the combustible gas, prevent discharge of carbon monoxide, which is a toxic gas, and prevent backward flow of the flame through the quenching mesh.

Abstract: A nuclear power plant includes a nuclear reactor containment structure housing a nuclear reactor, a pressure vessel containing condensed water therein and having a receiving space located lower than a bottom of the containment structure, a release pipe connecting the containment structure to the pressure vessel such that water vapor and fission products generated in the containment structure in the event of an accident is capable of flowing into the pressure vessel, and a recovery pipe connecting the pressure vessel to the containment structure such that the condensed water received in the pressure vessel is capable of flowing into the containment structure. When a level of the condensed water received in the pressure vessel is higher than a water level in the containment structure, the condensed water flows from the pressure vessel toward the containment structure by a water head difference.

Abstract: An apparatus for passively cooling and retaining molten core material discharged from a damaged reactor vessel during a severe accident in the nuclear plant including: a molten core material retention tank to retain molten core material; a compressed gas tank storing high-pressure inert gas; a cooling water storage tank being installed higher than the molten core material retention tank; and a mixing means. The molten core material retention tank includes an outer retention vessel having at least one coolant hole, a porous protection vessel formed at an inside of the outer retention vessel, and a gravel layer formed between the outer retention vessel and the porous protection vessel. The apparatus can be installed in a reactor cavity without changing the compartment structure of a containment building, and makes it possible to prevent a steam explosion during the cooling process for the ultrahigh-temperature molten core material and to secure the reliability of the cooling process.

Abstract: An apparatus for passively cooling and retaining molten core material discharged from a damaged reactor vessel during a severe accident in the nuclear plant including: a molten core material retention tank to retain molten core material; a compressed gas tank storing high-pressure inert gas; a cooling water storage tank being installed higher than the molten core material retention tank; and a mixing means. The molten core material retention tank includes an outer retention vessel having at least one coolant hole, a porous protection vessel formed at an inside of the outer retention vessel, and a gravel layer formed between the outer retention vessel and the porous protection vessel. The apparatus can be installed in a reactor cavity without changing the compartment structure of a containment building, and makes it possible to prevent a steam explosion during the cooling process for the ultrahigh-temperature molten core material and to secure the reliability of the cooling process.