Critical Review of Naphthenic Acid Corrosion

Abstract Naphthenic acid corrosion continues to be a reliability issue in refinery distillation units. A review of the subject is presented herein with special focus on field and laboratory data and on areas where research is needed. The review shows that several parameters are known to affect the corrosion process and their individual effect on crude corrosivity are somewhat understood. However, their combined effect is still subject to much controversy. The determination of a critical factor - naphthenic acid content - is still not standardized. It is shown herein that, by arranging the literature findings into three groups (1) furnace tubes and transfer lines, (2) vacuum column and (3) side cut piping, a better agreement of the literature data is achieved.