| High temperature corrosion, caused by organic acids and sulfur compounds, continues to cause reliability issues in petroleum refineries. However, neither total sulfur contents measured by elemental analyses nor total acid contents measured by total acid number (TAN) have been found to correlate well with corrosivity.;A fundamental study of the relationships between refinery corrosivity and chemical properties of sulfur and organic acid species has been performed. The corrosion tests of model oil mixtures as well as virgin Athabasca bitumen were carried out in a test unit that simulates corrosion found in refinery vacuum distillation towers. The results show that not only content but molecular weight and structure of the acids, and the structures of sulfur species influence high temperature corrosion. These factors need to be considered to improve the reliability of petroleum corrosivity assessment. |
