Two-stage hydrocracking method used for producing high-quality jet fuel

Abstract

The invention discloses a hydrocracking method used for producing high-quality jet fuel from inferior raw materials. The hydrocracking method comprises following steps: (1) inferior raw material oil is subjected to hydrofinishing reaction; (2) a hydrofinishing effluent is subjected to gas-liquid separation, and an obtained liquid material is subjected to fractionation; (3) tail oil obtained via fractionation is subjected to hydrocracking reaction, wherein a hydrocracking reaction zone comprises a hydrocracking catalyst I and a hydrocracking catalyst II with different molecular sieve contents; and (4) a hydrocracking effluent is subjected to separation, and an obtained liquid product is subjected to fractionation so as to obtain corresponding products. The upper part of the hydrocracking reaction zone is filled with the hydrocracking catalyst I; the hydrocracking catalyst I possesses relatively high aromatic hydrocarbon transformative capacity, and is capable of transforming aromatic hydrocarbons in heavier components of the raw materials into smaller molecules, and distributing the smaller molecules into heavy petroleum and jet fuel fractions; the lower part of the hydrocracking reaction zone is filled with the hydrocracking catalyst II; and the hydrocracking catalyst II possesses relatively high hydrocarbon alkyl cracking capacity. The two catalysts are combined, so thathydrocracking product quality is improved obviously, and especially, smoke point of jet fuel fractions is increased.

Description

technical field [0001] The invention relates to a hydrocracking method, in particular to a two-stage hydrocracking method capable of producing high-quality jet fuel. Background technique [0002] As the market demand for middle distillates continues to increase, refineries are required to produce more middle distillates. The new fuel standard puts forward stricter requirements on the indicators of gasoline and diesel. Obviously, primary processing methods and FCC technology can no longer meet the market's requirements for clean fuels. The hydrocracking process is not only a secondary processing method to lighten heavy raw materials, but also an important means to obtain high-quality jet fuel and clean diesel from inferior raw materials. [0003] In recent years, with the worldwide shortage of crude oil resources and the increasingly inferior quality of crude oil, the properties of raw materials processed by hydrocracking units have also become increasingly heavy and inferio...

AI Technical Summary

Problems solved by technology

However, this method needs to increase more equipment, and the circulation of kerosene fraction is relatively large, which increases the investment of the device, and the operation is more complicated

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