Performance of corrosion inhibitors on carbon steel in the geothermal environment of the Upper Rhine Graben (URG) depending on inhibitor concentration, temperature and hydrodynamic conditions—A laboratory study

• Published in: Geothermics Vol. 92; p. 102047
• Main Authors: Huttenloch, Petra, Zorn, Roman, Steger, Hagen, Schilling, Frank, Hater, Wolfgang
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.05.2021; Elsevier Science Ltd
• Subjects: Carbon dioxide; Carbon steel; Carbon steels; CO2 corrosion; Corrosion; Corrosion inhibitors; Electric power generation; Electrochemical impedance spectroscopy; Electrochemical studies; Electrochemistry; Electrode polarization; Geothermal energy; Geothermal power; Geothermal power plants; Graben; Hydrodynamic conditions; Imidazoline; Inhibitor performance; Inhibitors; Multiphase flow; Power plants; Spectroscopy; Two phase flow; Vapor phases; Weight loss; Weight loss tests; Electrochemical studies; Carbon steel; Hydrodynamic conditions; Inhibitor performance; Weight loss tests; CO2 corrosion
• ISSN: 0375-6505; 1879-3576
• DOI: 10.1016/j.geothermics.2021.102047

•Performance of amine and imidazoline based corrosion inhibitors in artificial geothermal brine.•Influence of temperature and different hydrodynamic conditions.•Weight loss tests at elevated temperature and pressure in the liquid and the gas phase.•Development of a mounting rod for simulating flow conditions for electrochemical measurements. The effectiveness of amine and imidazoline-based corrosion inhibitors on carbon steel was compared in CO2 saturated artificial geothermal water. Weight loss tests were carried out under the influence of the stirring speed in accordance with the conditions that exist on the production side (160 °C) and the injection side (80 °C) in geothermal power plants in the Upper Rhine Graben (URG). Corresponding to a possible two-phase flow, the corrosion behavior and inhibitor performance in the liquid and the gas phase was investigated. In addition, depending on the inhibitor concentration and various hydrodynamic conditions, electrochemical tests such as potentiodynamic polarization and electrochemical impedance spectroscopy (80 °C) were carried out.