Active control of oxygen in molten lead–bismuth eutectic systems to prevent steel corrosion and coolant contamination

The thermodynamic basis for controlling oxygen level in lead–bismuth to prevent steel corrosion and coolant contamination is examined. The operational conditions, including the thermodynamic activity of oxygen, cover gas oxygen partial pressure, mixtures of H2 and H2O (steam) to obtain such low oxygen partial pressure (<10−24 atm or around 10−6 wt% in lead–bismuth), and the voltage signals of one type of oxygen sensors (with a solid electrolyte and molten bismuth reference electrode) are calculated. These results provide the guidance to implement the oxygen control technique.