Corrosion of multiphase flow pipelines: the impact of crude oil

The control of multiphase flow corrosion during oil production is a challenging task. In this review, the impact of crude oil on pipeline corrosion is broadly discussed, with the notion to reduce corrosion risks of pipelines in aggressive field conditions. First, the properties, emulsion stability, and multiphase flow patterns of crude oil fluids are concisely summarized and correlated to the corrosion behavior. Second, for proper evaluation of the corrosiveness of the oil-brine mixtures, related corrosion test methods and experimental techniques are critically evaluated. Third, the effects of crude oil on corrosion inhibition are conceivably attributed to four aspects, i.e. the entrainment of water, the wetting by crude oil, the partitioning effect, and the modification of the corrosion product layers. Fourth, the presence of crude oil may consume more corrosion inhibitors; however, the inhibitors can produce additional benefits on corrosion mitigation in oil-brine mixed conditions, such as altering the surface wettability to hydrophobic and enhancing the entrainment of water. Finally, some ideas to reduce pipeline corrosion are proposed and future research viewpoints are discussed.