The corrosion potential is a useful parameter to monitor the water chemistry of a Nuclear Power Plant (NPP). However the harsh conditions in the core of a nuclear reactor being the temperature, pressure and the presence of an intense radiation field makes it difficult to construct a reference electrode for this location. An attempt has been made to construct such a reference electrode based on the well-known Yttrium Stabilised Zirconia (YSZ) membrane electrode. The YSZ electrode has been tested under PWR conditons in the Callisto loop of the BR2 MTR. . The corrosion potentials measured had values between -750 and – 800 mV SHE. The reference electrodes were mechanically intact after one year of testing. The electrochemical response was however not anymore reliable as the electrode resistance had decreased in time. Originally this was attributed to leaking of the ceramic-metal sealing causing "short circuit" in the reference electrode. Recent tests show however that the YSZ (9 weight percent Yttrium) used up till now for the electrodes is not fully resistant to high temperature water. Depending on the material structure the life time varies between a few weeks to one year.
|Title of host publication||Water chemistry in nuclear reactor systems|
|Place of Publication||Berlin, Germany|
|State||Published - 15 Sep 2008|
|Event||International conference on water chemistry of nuclear reactor systems - VGB, Berlin|
Duration: 14 Sep 2008 → 18 Sep 2008
|Conference||International conference on water chemistry of nuclear reactor systems|
|Period||2008-09-14 → 2008-09-18|