| Title | Corrosion Evaluation of Steels Under Geothermal CO2 Supercritical Conditions |
|---|---|
| Authors | Francois ROPITAL, Jean KITTEL |
| Year | 2020 |
| Conference | World Geothermal Congress |
| Keywords | corrosion, supercritical CO2, steels |
| Abstract | Corrosion is one of the major issue in the development of high enthalpy geothermal systems. In some fields, the CO2 pressure and the temperature are respectively greater than 77 Bar and 31°C, and the supercritical conditions of CO2 can lead to severe corrosion damages for carbon and stainless steels geothermal equipment. If supercritical CO2 can occur naturally in a reservoir, it is also a promising heat transmission fluid for enhanced geothermal systems (EGS). The quantity of water associated with the supercritical CO2 is also an important parameter. In order to study theses effects, experimental tests have been performed in autoclaves in both CO2 and water phases. Carbon steels and several stainless steels grades (AISI 430, 304L, 316L, 22-05 duplex) have been tested at 110°C under 160 bar of CO2 and different water compositions. Carbon steels coupons suffer uniform corrosion damages and AISI 430 stainless steel more localize degradation. This work is in progress in more CO2 supercritical conditions. |