steam generator heated sodium characterized by realize minds to prevent stagnation of sodium and catastrophic explosions, including a central shaft outlet with valve of ritewang

摘要

1387054 Liquid sodium steam generator FOSTER WHEELER CORP 2 March 1972 [3 March 1971] 9877/72 Heading F4A In a liquid sodium steam generator a pressure vessel 12 encloses a plurality of water/steam tube assemblies 40 which are arranged around a sodium/water reaction relief channel 81 defined by collars 70, and which are immersed in liquid sodium which enters at 52 and moves within flow shroud 60 to outlet 58; each tube assembly 40 comprising an inner tube 42 open at both ends which carries water from inlet chamber 32, and an outer tube 44 closed at its lower end which delivers steam to outlet chamber 34. The tube assemblies 40 pass loosely through alternately arranged baffles 66, 68 extending from the relief channel 81 and supported by tie rods 80; baffles 66 having gaps adjacent the flow shroud 60 and baffles 68 having gaps only adjacent the channel 81 causing the sodium to flow across the tube assemblies. Collars 70 have one way valves in the form of trap doors 82 which only open upwardly and are arranged adjacent baffles 66 to ensure that sodium can only flow down adjacent the channel at baffles 68. In the event of a sodium water reaction, reaction products can be vented through channel 81 pushing up the doors 82. Some sodium becomes trapped between the pressure vessel 12 and the flow shroud 60 to provide a stagnant insulating layer, intermeshing plates 86 being provided to prevent the escape of this layer.