| Popis: |
Potassium nitrate and sodium nitrate in mixing proportion of KNO3–NaNO3 40-60 wt% (also called solar salt) has been successfully used for over a decade as a heat storage medium for concentrated solar power plants. At temperatures of 550 ºC, reached in state-of-the-art solar tower systems, corrosion of metallic components in contact with solar salt can become an issue and has caused leaks and plant shut-downs in recently built tower projects. While the corrosion rates of several materials have been determined for different temperatures in static molten salt immersion experiments, there is a lack of corrosion data for dynamic inservice conditions. Fluid dynamics and scale-up are two factors that can influence the corrosion phenomena. In this work, corrosion studies were carried out on austenitic stainless steel (SS) (AISI 316L) and ferritic steel (AISI 430) under dynamic conditions, with long-term immersion in solar salt, on a pilot scale. It was found that AISI 316L steel forming more adherent oxides, presented a significantly lower corrosion rate than the AISI 430 steel, due to the formation of a protective FeCr2O4 layer, making it less susceptible to corrosion. The measured corrosion rates are presented and compared to static corrosion tests. info:eu-repo/semantics/publishedVersion |
