Abstract
The emergency core cooling system of a pressurized water reactor (PWR) has been shown to be susceptible to corrosion-related problems. Since 1996, much research has been undertaken to solve the sump clogging issue in PWRs, including a recent study, “Evaluation of Post-Accident Chemical Effects in Containment Sump Fluids to Support GSI-191,” that has become the industry standard. However, despite more realistic results than previous studies, the data from this report are still not a conservative estimate as several important environmental factors were neglected, including flow conditions and temperature transients. For the current research, the flow and temperature conditions are assessed and the release rates of aluminum are compared to the industry standard. Electrochemical measurements are used since the corrosion rates of the materials in the reactor containment are essential to understanding how much of a danger the corrosion products are to the recirculation pump. It was found that velocity and temperature had large effects on the release rate, although pH also had a small effect. This is as expected as higher temperatures lead to faster reaction kinetics and more favorable thermodynamics. Higher velocities also lead to higher corrosion rates since advection will dominate over diffusion. The current study’s measured corrosion rates, when compared with the industry standard corrosion rates, were approximately an order of magnitude higher.
