A method for enhancing the quality stability of hydrocracking products

Abstract

The invention discloses a method for enhancing the quality stability of a hydrocracked product. The method comprises the following steps: mixing a hydrocracking raw material and hydrogen, enabling themixture to enter a hydrocracking pretreatment reactor for refining reaction and enabling a reaction effluent to enter a hydrocracking reactor for hydrocracking reaction, wherein the hydrocracking reactor is internally provided with four hydrocracking catalyst beds; hydrogenation aftertreatment catalyst beds are arranged at the bottom of the hydrocracking reactor; when the conversion rate of a fraction at the temperature of higher than 350 DEG C in the hydrocracking raw material is 70-79%, the hydrogenation aftertreatment catalyst beds are arranged between a second hydrocracking catalyst bed and a third hydrocracking catalyst bed and between the third hydrocracking catalyst bed and a fourth hydrocracking catalyst bed respectively; the volume ratio of a hydrogenation aftertreatment catalystpacked in the hydrocracking reactor to a hydrocracking catalyst packed in the hydrocracking reactor is 1: (6-8); and the hydrocracked product is separated, so as to obtain various products. Accordingto the method, the quality stability of the hydrocracked product can be improved.

Description

technical field [0001] The invention relates to a method for enhancing the quality stability of hydrocracking products, in particular to a method for improving the quality stability of heavy naphtha products in late hydrocracking products during long-period operation. Background technique [0002] The hydrocracking process is under the action of hydrogen, high temperature, high pressure and catalysts to hydrodesulfurize, hydrodenitrogenate, polycyclic aromatic hydrocarbons, hydrosaturation and ring-opening cracking of heavy distillate oils (VGO, CGO, DAO). The process of converting into light oil and middle distillate oil has the characteristics of flexible operation, good product quality and environmental friendliness. As one of the main processes for the deep processing of heavy distillate oil, it is not only the production of light oil products in the refining industry It has become an important means of petrochemical enterprises, and has become the key technology of petr...

AI Technical Summary

Problems solved by technology

[0010] Aiming at the problems in the prior art that the olefins that commonly exist in the late stage of the hydrocracking reaction process using post-treatment catalysts exceed the standard, that is, the bromine index of heavy naphtha is too high, the mercaptans are too high, and the sulfur of aviation fuel products exceeds the standard. The use of grading and temperature control provide a method to improve the quality stability of hydrocracking products

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