Application of vapor phase corrosion inhibitors for contaminated environments

Abstract

Availability and accessibility to clean water for industrial applications such as hydrotesting and hydrostatic testing of pipelines, vessels, and plumbing distribution systems has been a challenging task especially when the job sites are in remote locations. When contaminated water is used in these tests, corrosion of the metallic components of the systems, during and after testing become a major concern. Vapor-phase corrosion inhibitors (VCI), can be added to water in small concentrations to prevent corrosion during testing, during wet storage and after testing. These inhibitors are to prevent corrosion of metallic components in three phases, within the solution, at the water line, and above the water line. Three commercially available corrosion inhibitors were evaluated in this investigation. Laboratory studies are presented in this paper, showed the effectiveness of VCI products in both fresh and salt water applications. Average corrosion rate dropped from ~10 mpy for salt solution to less than 1-1.6 mpy when various inhibitors was added. The effectiveness of these inhibitors is remarkable in the fresh water (less than 0.4 mpy). Exposure of the steel samples to these inhibitors did not show any loss in mechanical properties. Both strength and ductility of the low carbon steel samples was maintained.