|The gas separation system with the absorption tower. |
Photo courtesy of Sigrún Nanna Karlsdóttir.
In Iceland, geothermal power is the country’s single largest source of energy. Geothermal steam, however, contains noncondensable gases (gases that are not easily condensed by cooling), such as carbon dioxide (CO2), hydrogen sulfide (H2S), hydrogen (H2), nitrogen (N2), methane (CH4), and argon (Ar), that are considered to be either greenhouse, corrosive, or toxic gases. A recent Icelandic regulation with a stricter guideline on atmospheric concentration of H2S, which took effect in 2014, has compelled the country’s geothermal industry to take actions that will reduce H2S emissions into the air.
To evaluate the corrosion resistance of the absorption tower, which is in contact with high concentrations of H2S, Sigrún Nanna Karlsdóttir, associate professor in the Industrial Engineering, Mechanical Engineering, and Computer Science Department at the University of Iceland and her colleagues at the University of Iceland and the Innovation Center Iceland conducted a study on the corrosion behavior of UNS S31603 while being exposed to the H2S cleaning process in the absorption tower.
More information on the study can be found in the CORROSION 2016 paper, “Corrosion Testing in H2S Abatement System at Hellisheidi Geothermal Power Plant in Iceland,” by S.N. Karlsdóttir, S.M. Hjaltason, and K.R. Ragnarsdottir.