Perspectives on selected alloys in contact with eutectic melts for thermal storage: Nitrates, carbonates and chlorides
Journal article, 2021

Increasing the operating temperature of molten salt-based concentrated solar power plants is of paramount importance to enable next-generation gas turbines and an overall increase in power conversion efficiency. The issue is how to mitigate the degradation of necessary metallic components in highly corrosive salt environments. In this study, three eutectic salt mixture candidates, nitrates, carbonates, and chlorides, are brought into contact with stainless steel (316H or 304L) and the FeCrAl alloy KanthalĀ® APMT. The post-exposure analysis is discussed in terms of the overall performance of each alloy as concerns mass change, scale growth, internal attack, and leaching. Significant reduction of corrosion is realised through the ability of KanthalĀ® APMT to form aluminium oxide species at the surface in contact with alkali nitrates and carbonates. On the other hand, aluminium is leached most efficiently in contact with chlorides, which causes a deeper attack on KanthalĀ® APMT than alloy 304L. The overall conclusion is that only by employing a holistic perspective on all individual measurements can a long-term performance estimation be formulated.

High temperature corrosion

Molten chlorides

Carburization

Carbonates

Laves phase

Thermal storage

Author

Esraa Hamdy Mohamedin

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Johanna Nockert Olovsjö

Kanthal AB

Christine Geers

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Solar Energy

0038-092X (ISSN)

Vol. 224 1210-1221

Driving Forces

Sustainable development

Subject Categories

Energy Engineering

Metallurgy and Metallic Materials

Corrosion Engineering

Areas of Advance

Energy

DOI

10.1016/j.solener.2021.06.069

More information

Latest update

8/10/2021