Technology for the Multifunctional Hydrothermal Treatment of Oil Residues (Mazut and Tar) on Catalysts with a Hierarchical Structure of Pores

A technology is proposed for the catalytic hydrothermal treatment of oil residues (mazut and tar) for the synthesis of high added value products, including marine fuel, that satisfy the contemporary technical and environmental requirements. The technology is based on using catalysts on an alumina support with a hierarchical structure of meso- and macropores and a high stability under severe process conditions. Data are presented from a physicochemical analysis of the chemical composition, textural and phase properties of fresh and waste catalysts for the three-stage processes of the hydrothermal treatment of mazut and tar. Variants of the implementing and combining this technology at Russian oil refineries to increase profits from oil refining are proposed on the basis of the material balance of each stage of these processes and the complex analysis of properties for the formed oil products. Introducing mazut hydrothermal treatment at oil refineries without secondary processes would improve the economic efficiency of mazut utilization by 84–170%, depending on the chosen process layout and the product box required for an enterprise. Tar hydrothermal treatment can be combined with the processes of delayed coking, catalytic cracking, and hydrocracking to increase the depth of treatment to 95% and enhance the production of such high-demand oil refining products as gasoline, diesel fuel, and marine fuel with sulfur contents of less than 0.5% and low-sulfur oil coke for the electrode manufacturing industry. The integration of tar hydrothermal treatment with secondary processes would improve the economic efficiency of tar utilization by 2–2.5 times, relative to delayed coking plants.