Deposition of hematite particles on alumina seal faceplates of nuclear reactor coolant pumps: Laboratory experiments and industrial feedback

Hemijska Industrija

关键词: particle;    adsorption;    fouling;    Zeta potential;    pressurized water reactor;   

DOI  :  10.2298/HEMIND110922101L

来源: DOAJ

【 摘 要 】

In the primary circuit of pressurized water reactors (PWR), the dynamicsealing system in reactor coolant pumps is ensured by mechanical seals whoseceramic parts are in contact with the cooling solution. During thestretch-out phase in reactor operation, characterized by low boric acidconcentration, the leak-off flow has been observed to abnormally evolve inindustrial plants. The deposition of hematite particles, originating fromcorrosion, on alumina seals of coolant pumps is suspected to be the cause.As better understanding of the adhesion mechanism is the key factor in theprevention of fouling and particle removal, an experimental study wascarried out using a laboratory set-up. With model materials, hematite andsintered alumina, the adhesion rate and surface potentials of theinteracting solids were measured under different chemical conditions(solution pH and composition) in analogy with the PWR ones. The obtainedresults were in good agreement with the DLVO (Derjaguin-Landau-Verwey-Overbeek) theory and used as such to interpret this industrial phenomenon.

【 授权许可】

Unknown