Experimental study on corrosion of steels for flue gas reheaters in a coal-fired power plant

The corrosion failures occurring in the back-end of coal-fired power plants are of great importance, and there are many decades of research experience of the corrosion issues before or in the flue gas desulfurization (FGD) unit, but the situation for flue gas reheaters (FGR) which are placed after FGD is rather different. In this paper, in-plant corrosion tests were performed and the corrosion mechanism was studied. The corrosion products were mainly iron oxides and the droplets entrained by the wet flue gas were the major cause. The wall temperature of the tubes in FGR should be kept at a high level to mitigate the corrosion.