Although liquid lead-bismuth eutectic (LBE) is a good candidate for the coolant in the subcritical transmutation blanket, it is known to be very corrosive to stainless steel, the material of the carrying tubes and the containers. Such a corrosion problem can be prevented by producing and maintaining a protective oxide layer on the exposed surface of stainless steel. The proper formation of this oxide layer critically depends on the accurate measurement and control of the oxygen concentration in the liquid LBE. YSZ (Yttria Stabilized Zirconia) oxygen sensors, using molten bismuth saturated with oxygen as the reference, have been utilized to measure the concentration of oxygen dissolved in the liquid LBE. In the first two years (5/2002-4/2004), calibration of oxygen sensors was performed using the experimental setup located in LANL. A set of calibration curves at temperature ranging from 300 0C to 500 0C has been obtained. A new experimental apparatus has been built up for calibration at higher temperature (5000C-700+0C). On the basis of the theoretical predictions, this new apparatus is currently being re-engineered to combat some problems originally unperceived at the early design phases. More experimental results will be generated using this new setup
after finishing the re-engineering. The proposed specific aims in the third year are:
1. To complete and fully test the new oxygen control and measurement apparatus;
2. To employ a more precise H2/H2O steam injection strategy for oxygen control instead of previous method of direct injection of O2;
3. To continue the sensor calibration by using our new setup at higher temperature ranges (500 0C to 700+0C);
4. To continue the numerical simulation of the oxygen concentration distribution in the liquid LBE for the new setup;
5. To determine oxygen dissolving rates under various conditions through numerical simulation and experimental measurement.
Lead-bismuth alloys; Stainless steel – Corrosion; Stainless steel – Oxidation; Oxygen – Measurement
Chemical Engineering | Engineering
Developing a sensing system for the measurement of oxygen concentration in Liquid Pb-Bi Eutectic.