Abstract
Understanding the mechanisms that lead to localized corrosion in oil and gas pipeline is of great interest to corrosion engineers worldwide. In a research program which examined corrosion under slightly sour conditions due to an H2S/CO2 environment, experimental studies were carried out to identify the environmental parameters with the most influence on the likelihood of localized corrosion. Observations of localized corrosion that occurred in slightly sour conditions in a large scale flow loop under single phase and multiphase flow were used to develop a better understanding of how bulk solution conditions can affect the growth of the corrosion product layers, over time, and their relationship to localized corrosion. It was shown that the solution bulk pH, ionic strength, and concentrations of carbonate and sulfide species are the major factors related to development of localized corrosion in a slightly sour environment. The experimental data was then analyzed and used to develop a correlation to relate these parameters to the likelihood of localized corrosion.
