Steam generator heated with liquid metal

Claim 1

A liquid-metal heated vapor generator, comprising a vertically extending pressure vessel having a tubular wall portion and upper and lower spherical end portions, an upper and lower tube sheet cooperatively associated with said upper and lower spherical end portions and jointly therewith defining an upper vapor chamber and a lower liquid chamber, respectively, a plurality of tubes extending substantially throughout the interior of said vessel in a planar serpentine configuration and having their upper and their lower ends sealed through said upper and lower tube-sheets, respectively, and in fluid communication with said vapor chamber and said liquid chamber, means for admitting a heated liquid metal to said vessel, means for conducting said liquid metal about said tubes in good heat-exchange relation with said serpentine configuration, and establishing a body of liquid metal in said vessel, means for withdrawing said liquid metal from said vessel, means for admitting a pressurized liquid to be vaporized to said liquid chamber, means defining a gas space above said body of liquid metal, means for admitting a pressurized inert gas to said gas space, said tubes being of sufficient length to permit conversion of said pressurized liquid into pressurized vapor as it issues from said upper-tube-sheet into said vapor space, said tubes also being nested together in closely spaced relation to each other in a direction transverse to the direction of flow of the liquid metal, said tube nest being encompassed by a tubular wrapper disposed in internally spaced relation with the tubular wall portion of the vessel, a tubular shield encompassing said wrapper and jointly with said wrapper and the vessel wall portion forming two annular spaces for stagnant liquid metal, and means for withdrawing said pressurized vapor from said vapor space.