Study of atypical organosulfur deposits in the heat-exchange equipment of primary oil refining units

Abstract

The formation of deposits in rectification columns and heat exchange equipment leads to violations of the technological process, and in some cases to an emergency shutdown of the equipment. To prevent deposits, it is necessary to know their chemical composition and genesis. We present the results of studying atypical organosulfur deposits in the heat exchange equipment of primary oil refining units. The structure and composition of the deposits were analyzed by scanning electron microscopy, and the chemical composition was determined using X-ray fluorescence analysis. It is shown that elemental sulfur present in the composition of the deposits acts as an additional corrosion factor that affects corrosion processes. Sulfur, being adsorbed on the surface of the equipment, blocks the access of the corrosion inhibitor to the metal surface thus reducing the effectiveness of the reagent. The neutralizer supplied to the helmet line of the atmospheric column can neutralize the acidic components (HCl and H2S), but it is not able to neutralize the effect of sulfur on the inner surface of the metal of air coolers. The results obtained can be used to improve the control of heat exchange equipment of primary oil refining units.