February 21, 2018: PhD public defence - Gabriele Manfredi - Oxygen sensors and electrochemical oxygen pumps for lead alloy cooled nuclear systems - ULB

Name: Gabriele Manfredi

Date: February 21, 2018 17:00 h

Venue: 

Université Libre de Bruxelles
Campus de la Plaine, FORUM G
Boulevard du Triomphe - 1050 Bruxelles


Oxygen sensors and electrochemical oxygen pumps for lead alloy cooled nuclear systems

MYRRHA, a Multi-purpose hYbrid Research Reactor for High-tech Applications is currently under development at the Belgian nuclear research center SCK•CEN. 
It is the very first prototype of a nuclear reactor driven by a particle accelerator in the world. Lead-Bismuth Eutectic (LBE) has been selected as spallation neutron source and as primary reactor coolant. 

Oxygen control strategy has been defined to mitigate undesirable liquid metal corrosion occurring between the steel surface of the main components of MYRRHA and the LBE itself. The development of a reliable oxygen sensor and control device beyond the state-of-the-art for operation in the conditions foreseen in MYRRHA is therefore crucial.  

A potentiometric oxygen sensor based on the use of yttria partially stabilized zirconia as solid electrolyte combined respectively with air/perovskite oxides e.g. Lanthanum Strontium Manganite (LSM) and Lanthanum Strontium Manganite - Gadolinium Doped Ceria (LSM-GDC), Cu/Cu2O, In/In2O3 and LBE/PbO reference electrode has been developed and operated successfully between 200 and 450 °C in oxygen saturated LBE overcoming the operating temperature limit of previously used Bi/Bi2O3 and air/Pt reference electrode oxygen sensors being of 280 °C  and  300 °C approximately.

An electrochemical oxygen pump based on the use of yttria partially stabilized  as solid electrolyte and air/Lanthanum Strontium Manganite has been tested to add and extract oxygen from LBE. The oxygen addition might be limited by the oxygen reduction kinetics at the air/LSM side while, the oxygen extraction is limited at high oxygen potential by the diffusion of oxygen ions through the solid electrolyte and at low oxygen potential by the oxygen diffusion in the liquid LBE. 

 

 

Promotor:

  •  (ULB) Claudine Herman-Buess
SCK•CEN mentors:
  • Lim Jun

Click here for a list of obtained PhD degrees.