Liquid alkali metal-water, tube-in-shell steam generators
AssigneeNational Nuclear Corporation Limited
InventorsGeorge F. Firth, Owen Hayden
Life of this patent
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Abstract
A proportion of the liquid metal flow passing through a fast reactor steam generator unit (SGU) is diverted past the outlet to a quiescent zone in the region of immersed tube-to-tubeplate welds at the water entry ends of the tubes, into which zone are given off any hydrogen bubbles which may result from a water leak into the liquid metal. The liquid metal in this zone is caused to flow through a weir system above which there is a gas space for collection of hydrogen, suitable means being provided for detection of hydrogen in this space. The hydrogen is entrained at the water inlet tube plate, the invention making use of the slow solution rate of hydrogen in sodium at lower temperatures prevailing in the quiescent zone at the water inlet end.
Claims7
In an liquid alkali metal-water, tube-in-shell steam generator with tube-to-tubeplate connections for water entry ends of the tubes immersed in the liquid alkali metal, the improvement comprising means for forming in the vicinity of said tube-to-tubeplate connections a gas space constituting a bubble collection zone above a localized surface of the liquid alkali metal, which localized surface is separate from any other surface level of the liquid alkali metal in the steam generator, means for directing any hydrogen bubbles arising in the region of said immersed tube-to-tubeplate connections to said surface for escape as gas into the collection zone, and means for monitoring for the presence of hydrogen in the collection zone.
Dependencies are inferred from the claim text.