EMERGENCY CORE-DISRUPTIVE COOLING SYSTEM FOR NUCLEAR POWER REACTOR Russian patent published in 1996 - IPC

FIELD: nuclear power engineering. SUBSTANCE: system has concrete cavity filled with water in case of accident. Cavity is provided with manhole and houses reactor vessel and bottom heat insulation placed under it to form, together with bottom, heat-transfer channels joined with uptake channels, central inlet channel, and side inlet channels connected to the latter. All of them, brought together, form circulating loop for cooling down core melt inside reactor vessel. Water is admitted through side inlet channels to central inlet channel wherefrom it is passed to cooling channels for cooling down core melt through reactor vessel bottom; steam-waver mixture produced in the process goes up via uptake channels above cavity water level wherein steam is separated. Water goes through manhole downwards to concrete cavity bottom. In case of reactor vessel disruption, melt is passed through central inlet channel to middle part of partition made of light-melting material. Heat bursts throw water out of side inlet channels and uptake channels. Melt destructs cords wherefrom shut-off valve plugs are suspended. Plugs go down and additional heat bursts crush them through their plugs, whereupon shut-off valves close and remaining water from side inlet channels will be expelled by steam through antishock channels. Middle part of partition melts and molten material is discharged to dry trap. Thermal dampers prevent thermal shock on accumulating container components. After intermediate accumulating thermal header is heated above initial temperature of heat pipes, melt heat is imparted to water in uptake section. Heat transfer is afforded by water (steam-water mixture) circulation over the following loop: manhole (downtake section), concrete cavity, clearance, uptake section, uptake pipes (uptake section). EFFECT: improved reliability of core melt cooline inside reactor vessel, eliminated contact between large mass of melt and water, that is, avoided release of large quantity of energy of steam of heavy-power steam burst. 6 cl, 7 dwg