| About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
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| Symposium
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Advances in High-Temperature Oxidation and Degradation of Materials for Harsh Environments: A SMD and FMD Symposium Honoring Brian Gleeson
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| Presentation Title |
Effects of Chlorides and Sulphates on High-Temperature Corrosion of Chromia-Forming Fe-Based Alloys in Wet CO2 Gas |
| Author(s) |
Xuteng Xi, Yuchen Cai, Jianqiang Zhang, Brian Gleeson, David Young |
| On-Site Speaker (Planned) |
Jianqiang Zhang |
| Abstract Scope |
Oxyfuel combustion makes CO2 sequestration feasible, but produces a corrosion problem. In addition, alkali chlorides and/or sulphates are often present, negatively affecting the corrosion resistance of chromia-forming alloys. This paper investigated corrosion behavior of ferritic alloys, Fe-25Cr and Fe-25Cr-2Mn-1Si, and austenitic alloys, Fe-25Cr-20Ni and 310SS coated with either chlorides (NaCl + KCl) or sulphates (Na2SO4 + K2SO4) in Ar-60CO2-20H2O at 650oC for up to 300 h.
The results showed that both Fe-25Cr and Fe-20Ni-25Cr experienced breakaway corrosion in wet CO2 gas. The addition of Mn and Si in both alloys converted breakaway oxidation to protective oxidation by forming protective silica sublayers and external Mn-rich oxides. With the presence of chlorides, all alloys suffered accelerated corrosion by forming porous corrosion products. In the presence of sulphates, Fe-oxide precipitates were found inside the salt layers which is attributed to the iron oxide fluxing due to the formation of low melting Na2O-Na2SO4 solution. |