|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||High Temperature Corrosion of Structural Materials
||Mechanism of High Temperature Corrosion of Steel by Naphthenic Acids and Sulfidation
||Peng Jin, Winston Robbins, Gheorghe Bota
|On-Site Speaker (Planned)
In crude oil refineries, naphthenic acid corrosion and sulfidation (corrosion by sulfur compounds) between 220-400˚C may compromise facility integrity and have been extensively studied. Although the iron sulfide scale formed in sulfidation is commonly considered to be protective, the mechanism of scale protectiveness is not fully understood making corrosion difficult to predict. Previously, we reported that protective scales produced by simultaneous naphthenic acid corrosion and sulfidation under the stagnant condition contained oxides (magnetite). Here we report the formation of oxides in protective scales formed under the replenishing conditions. It appeared that both naphthenic acid corrosion and sulfidation proceed on the outer surface of the scale adjacent to steel surface. Over time, growth and spallation achieve steady state thickness for an adherent inner scale. The corrosion is postulated to be controlled by the solid state diffusion of iron through the inner scale.
||Planned: Supplemental Proceedings volume