High-temperature corrosion data and mechanisms for T122, Super304H and HR3C after 15 years in 1000MW ultra-supercritical power plant

ABSTRACT

The high-temperature corrosion of heat-resistant steels T122, Super304H and HR3C used for the inlet of a header in a 1000 MW ultra-supercritical power plant for 15 years was investigated. The steam temperature and pressure were about 610 °C and 28 MPa, respectively. The morphology and phase compositions of the corrosion products formed on the investigated tubes were analysed using X-ray diffraction and a scanning electron microscope with an energy dispersive spectroscopy detector. The results showed that the thickness of the corrosion products on the tube fireside was larger than that on the steam-side of the investigated tubes, which was due to the sulphur in the flue gas. The thickness rank of the corrosion products on the investigated steels was T122 > Super304H > HR3C. Defects including micro-cracks and voids were found in the corrosion products on both sides of the three tubes, which led to the breakaway of corrosion products.

KEYWORDS:

• T122
• Super304H
• HR3C
• fireside
• steam-side
• corrosion
• long term service

Acknowledgments

This work was financially supported by the National Key Research and Development Program of China (No. 2021YFC3001801).

Author statement

Haomin Wu: Acquisition of data, Drafting the manuscript. Shuo Wang: Revising the manuscript critically for important intellectual content. Qinxin Zhao: Revising the manuscript critically for important intellectual content. Zhiyuan Liang: Conception and design of study, Revising the manuscript critically for important intellectual content.

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Additional information

Funding

This work was supported by the National Key Research and Development Program of China [2021YFC3001801].