METHOD OF HYDROGENATION REFINING OF RESIDUAL OIL STOCK Russian patent published in 2020 - IPC C10G65/04 C10G45/38 C10G45/50 

FIELD: oil, gas and coke-chemical industries.

SUBSTANCE: invention relates to oil refining, particularly, to method of hydrogenation refining of residual oil stock on stationary layers of catalysts. Method includes stages of: hydrodemetallization, which is carried out in two parallel located alternately operating reactors, hydrodenitrogenation, hydrodesulphurisation and subsequent distillation of the obtained hydrogenation with separation of the rectification residue as residual marine fuel with sulphur content of not more than 0.5 wt. %. Duration of operation of each pre-reactor of hydrodemetallization stage makes at least 5000 hours. Catalytic system of pre-reactors is represented by layers located along the direction of movement of the gas feed mixture in sequence, starting from top dispenser of pre-reactor: First layer making 15–25 vol. % of pre-reactor - inert ceramic active filtration material for removal of mechanical impurities from residual oil stock, having inner porosity of at least 75 %, 2^nd, 3^rd and 4^th layers, making 75–85 vol. % of wide-porous alumina composite material containing oxides of active metals - Ni, Co, Mo, V, designed to reduce deposits of asphaltenes, organometallic compounds, resins, polycyclic aromatic hydrocarbons and coke precursors, wherein content of metal oxides in 2^nd layer is not more than 3 wt. %, in 3^rd layer is not more than 7 wt. %, in 4^th layer is not more than 14 wt. %, effective diameter of pores in 2^nd layer - not more than 40 nm, in 3rd layer - not more than 38 nm, in 4^th layer - not more than 35 nm. Hydrodenitrogenation step is carried out in a reactor, aluminium-nickel-molybdenum catalyst loaded on alumina carrier with a specific surface area of not less than 150 m²/g, a pore volume of 0.4–0.9 cm³/g, at least 30 % of which is in pores with diameter of 100–500 nm and not more than 70 % are pores with diameter of 7–10 nm and total content of active metals in terms of nickel and molybdenum oxides of not less than 25 wt. %. Hydrodesulphurisation step is carried out in a reactor loaded with an alumino-cobalt-molybdenum catalyst on an aluminum oxide support with specific surface area of not less than 200 m²/g, a pore volume of 0.4–0.9 cm³/g, at least 20 % of which is in pores with diameter of 100–500 nm and not more than 80 % of pores with diameter of 7–10 nm and a total content of active metals based on cobalt oxides and molybdenum not more than 20 wt. %.

EFFECT: proposed method of hydrogenation refinement of residual oil stock allows processing of high-viscosity atmospheric oil residues (fuel oil) to obtain low-sulphur residual marine fuel, which meets requirements of GOST 32510-2013, output of which is up to 95 wt % on raw material; wherein raw material with high content of sulphur (up to 5 wt %) and heavy metals - nickel and vanadium (up to 500 mg/kg) can be involved in processing, and absence of necessity to recycle distillate fractions allows simplifying process circuit.

6 cl, 3 ex