Corrosion testing of materials in simulated superheated geothermal environment

Abstract

This paper reports the results of corrosion study for carbon steel, austenitic stainless steel, as well as titanium and nickel-based alloys which were tested in a simulated superheated geothermal environment (SSGE) in flow-through reactors to investigate the corrosion behaviour to aid in the future material selection for high temperature deep geothermal application. The testing fluid was superheated steam (T = 350 °C and P = 10 bars gauge) containing H2S, CO2 and HCl with condensate of pH = 3. The corrosion rate for all samples was negligible but carbon steel was prone to localized damage under a magnetite film with a sulphur rich sublayer.