Pb and Pb-Bi are known to be very corrosive to structural materials at elev
ated temperatures. In recent studies, the necessity of measurement and cont
rol of the oxygen concentration in the liquid metal in order to safely oper
ate a liquid Pb or Pb-Bi loop has been shown. The dynamic behaviour of the
gas phase oxygen control system (OCS), which was developed at Forschungszen
trum Karlsruhe (FZK), is investigated with respect to diffusion as the limi
ting process of oxygen exchange between the gas phase and the liquid metal.
In this paper the development of a physical model for this diffusion proce
ss is described and compared to experimental results of a stagnant liquid P
b-Bi system. The experimental findings are in very good agreement with the
theoretical equations describing the thermodynamic and kinetic behaviour of
such a system. Recent investigations in a Pb-Bi loop at the Karlsruhe Lead
Laboratory (KALLA) indicate that this gas phase OCS is a promising candida
te system for an accelerator-driven subcritical system (ADS). (C) 2001 Else
vier Science B.V. All rights reserved.