As environmental sulfur limits become more stringent, there has been a recent surge in preferential and localized corrosion in amine units. This has occurred even with HIC (Hydrogen Induced Cracking) resistant steels and in equipment where velocity limits are not exceeded.

Amine absorbers and associated rich amine piping particularly around the welds, downcomers and other turbulent locations are particularly vulnerable. In extreme circumstances, there has also been evidence of blistering, HIC cracking and widespread pitting in such steels.

This paper will discuss case histories of absorber damage and look at the importance of the synergies of operating parameters such as acid gas loadings, recirculation rates and amine concentrations in controlling corrosion.

Traditional inspection and analysis techniques have failed to predict or identify such damage. The most cost-effective means of identifying, inspecting, monitoring and minimizing corrosion will be discussed along with timely replacement strategies.