Inpurity Monitoring in Liquid Sodium Systems by Electrochemical Oxygen and Hydrogen Monitors

Abstract

Liquid sodium is used as the coolant in both primary and secondary circuits of the liquid metal fast breeder reactor. The oxygen content of the sodium has a profound effect upon the corrosion of structural materials and upon the tribology of materials pairs. A change in the hydrogen concentration in the sodium can signal excessive water-side corrosion in the steam generators or an oil leak from a pump. Changes in oxygen or hydrogen content in the secondary circuit may also indicate a leak of water into sodium. Thus, oxygen and hydrogen detectors can be used to detect steam generator leaks and are utilized as a part of the steam generator protection system. The performance of electrochemical cells for hydrogen and oxygen under both steady- state and simulated steam generator leak conditions is described.