New Sour Gas Corrosion Inhibitor Compatible with Kinetic Hydrate Inhibitor

The presence of hydrogen sulfide in high pressure gas systems causes several complications. Sour gas corrosion is a major concern in the oil and gas industry due to the presence of localized corrosion. At high pressures and low temperatures hydrates can occur. Sour gas decreases the pressure and increases the temperature at which hydrate formation occurs. Operators have used both corrosion inhibitors and kinetic hydrate inhibitors to decrease the capital requirements of developing sour high pressure gas systems. The development of sour gas corrosion inhibitors that are compatible with kinetic hydrate inhibitors is a major requirement for qualifying corrosion inhibitors for these applications. This paper describes laboratory work on the development of a new corrosion inhibitor by performing various performance and compatibility tests with kinetic hydrate inhibitor. The new corrosion inhibitor needed to meet various additional requirements which made the development process even more complex. The partitioning of a corrosion inhibitor between the oil and water phases has a significant impact on inhibitor selection and treatment strategy. General corrosion performance was addressed using mass loss and electrochemical data. Evaluation of localized attack was performed using vertical scanning interferometry (VSI). The main advantage of this approach is in providing quantitative data for product performance differentiation in the presence of localized corrosion.