Process method and system for combining hydrogenation and catalytic cracking

Abstract

The invention relates to the field of heavy oil processing, and discloses a process method and system for combining hydrogenation and catalytic cracking. The method comprises the following steps: (1)catalytic cracking raw oil is introduced into a catalytic cracking first lifting pipe to carry out a first catalytic cracking reaction, and a product of the catalytic cracking reaction is separated; (2) catalytic cracking heavy cycle oil and at least a part of optional catalytic cracking light cycle oil are added into a hydrogenation unit for carrying out a hydrogenation reaction, and a product ofthe hydrogenation reaction is separated to obtain hydrogenation cycle oil; and (3) a part of the hydrogenation cycle oil is introduced into the lower part of a catalytic cracking second lifting pipefor carrying out a catalytic cracking reaction; and a gasoline fraction and the other part of the hydrogenation cycle oil are introduced into the upper part of the catalytic cracking second lifting pipe and are subjected to a catalytic cracking reaction together with a catalyst and oil gas from the lower part of the second lifting pipe. Through the method provided by the invention, the heavy oil can be efficiently converted, low-olefin catalytic gasoline and catalytic diesel oil with a relatively high cetane number can be produced, the proportion of the diesel oil to the gasoline can be flexibly adjusted, and high yield of light oil can be achieved.

Description

technical field [0001] The invention relates to the field of hydrocarbon oil processing, in particular to a hydrogenation and catalytic cracking combined process method and a hydrogenation and catalytic cracking combined process system. Background technique [0002] At present, the world is facing the trend of crude oil becoming heavier and worse, while people's demand for heavy fuel oil is gradually decreasing, while the demand for light oil is greatly increasing. Therefore, refiners are pursuing the maximum conversion of residual oil. [0003] Among the various methods of lightening residual oil, high-quality paraffin-based heavy oil can be directly subjected to catalytic cracking to produce light oil products. Inferior high-sulfur and high-residual carbon residue oil is first subjected to hydrotreating, and the hydrogenated tail oil is then processed by catalytic cracking. The residue oil is hydrotreated to remove impurities such as metals, sulfur, nitrogen, etc., and t...

AI Technical Summary

Problems solved by technology

[0009] CN1388219A reduces the content of gasoline olefins by using the hydrogen donor components with a distillation range less than 400°C to react with gasoline, but when it is necessary to reduce the gasoline olefins and at the same time lighten the hydrogen donor, it cannot be balanced

However, since gasoline enters one of the risers separately to reduce olefins, there is a regenerated catalytic cracking catalyst with strong gasoline contact cracking ability, which leads to more gasoline cracking, and there is no external hydrogen donor to provide hydrogen source for gasoline, and gasoline needs to obtain hydrogen from itself. Part of the problem of gasoline condensation and coking is more, resulting in a large loss of gasoline yield, and because there is no hydrogen donor and gasoline fed together, the effect of reducing olefins is not good

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