Karlsdottir S.N.,Innovation Center Iceland Keldnaholt |
Karlsdottir S.N.,University of Iceland |
Thorbjornsson I.O.,Reykjavik University |
Ragnarsdottir K.R.,Innovation Center Iceland Keldnaholt |
Einarsson A.,Asbjorn Einarsson Consultants
NACE - International Corrosion Conference Series | Year: 2014
The IDDP-1 well in the Krafla geothermal field in Iceland is the first well in the Icelandic deep drilling project. The superheated steam from the well is extremely hot (450°C) with a 120 bar pressure at the wellhead. The IDDP-1 steam contains acid gas and is highly corrosive when it condenses. A test unit with eight different material types of heat exchanger tubes was set up in order to investigate the possibility of using the IDDP-1 steam directly for heat exchangers without prior removal of silica, sulfur and acid gases. The tube materials were three types of stainless steel, two titanium alloys, and two nickel alloys. In addition one carbon steel tube was added as a reference. The inlet temperature and pressure were 330-350°C and 52-62 bar. The steam condensed in the tubes with an outlet temperature of about 270°C. Severe problems were encountered in the use of steam traps at the outlet end of the tubes due to clogging of silica and they had to be replaced with orifice plates. This paper reports the results from the testing and inspection of the pipes including visual inspection, and microstructural and chemical composition analysis with SEM with XEDS. © 2014 by NACE International.
Valle N.,Center De Recherche Public Gabriel Lippmann |
Martinez Celis M.,Center De Recherche Public Gabriel Lippmann |
Lacaze J.,Inter - University Research and Engineering Center on Materials |
Thorbjornsson I.O.,Innovation Center Iceland Keldnaholt |
And 2 more authors.
Surface and Interface Analysis | Year: 2013
The benefit of the presence of Cr containing inserts inside ductile iron on the tribological properties of these materials has been recently demonstrated. In order to understand these improved properties, a secondary ion mass spectrometry (SIMS) and transmission electron microscopy investigation of these wear-resistant ductile cast irons has been performed. The results indicate that the principal change in the microstructure induced by inserts occurs in the inserts and in their surroundings where the formation of carbides with different sizes and compositions is observed: M3C, M7C3 and M23C6 (M stands for Fe and/or Cr). These are not pure binary carbides since among the different elements studied by SIMS, Cr, Fe, Mn and, to a lesser extent, Ni are soluble in these carbides. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.