Method and apparatus for initial purification of liquid metal heat exchange fluid

摘要

A method for removing oxides from a liquid metal heat exchange fluid following the initial startup of the heat exchange system fixes oxygen by locating an oxygen scavenging material in a drain tank. During initial fabrication and periods of maintenance metal surfaces of the conduits, heat exchange elements and other equipment become coated with an oxide layer. This invention eliminates the need for the sacrificial traps in the circulating system that are used to remove this initial oxide loading by placing an oxygen scavenging material in the drain tank. The drain tank is ordinarily provided to retain the inventory of liquid metal when it is not circulating in the heat exchange volume. A simple drain down of the liquid metal inventory can thereby remove from the liquid metal inventory essentially all of the oxide impurities that usually accompany an initial startup of such a system. As a result traps or other elements that were needed for this initial clean-up are unnecessary in the main circulation volume of the liquid metal.