Multiscaled Experimental Investigations of Corrosion and Precipitation Processes After Loss-of-Coolant Accidents in Pressurized Water Reactors

In a joint research project of the Zittau/Goerlitz University of Applied Sciences, the Technische Universitat Dresden, and the Helmholtz-Zentrum Dresden-Rossendorf, the main emphasis is the time-related assignment of simultaneous and interacting mechanisms at zinc sources and zinc sinks at boundary conditions of a loss-of-coolant accident (LOCA) in German pressurized water reactors (PWRs). The required experiments are carried out at semitechnical and laboratory scales.Zinc is used as a protective coating, e.g., for gratings in the containment, showing high corrosion resistance due to a gradual formation of passivating layers. In contrast, its long-term behavior during LOCA changes significantly under the influence of the coolant chemistry of German PWRs. As a consequence, installations in the containment act as zinc sources. Released zinc ions change the chemical properties of the coolant and could, e.g., lead to layer-forming depositions of zinc borates in the core, which increases the possibilit...