Method for prolonging quality stability of hydrocracking product

Abstract

The invention discloses a method for prolonging the quality stability of a hydrocracking product. The method comprises the following steps that hydrocracking raw materials and hydrogen gas are mixed to enter a hydrocracking pretreatment reactor for refining reaction; reaction effluents enter a hydrocracking reactor for hydrocracking reaction; four hydrocracking catalyst bed layers are arranged inthe hydrocracking reactor; when the conversion rate of fractions higher than 350 DEG C in hydrocracking raw materials is 90 to 99 percent, a hydrogenation posttreatment catalyst bed layer is arrangedat each of the top and the bottom of any one hydrocracking catalyst bed layer; the volume ratio of posttreatment catalysts filled along the material flow direction is (3 to 7):(5 to 15):(5 to 25):(20to 40):(30 to 50); the volume ratio of the hydrogenation posttreatment catalysts in the hydrocracking reactor to hydrocracking catalysts filled in the hydrocracking reactor is 1:(6 to 8); after hydrocracking products are separated, various products are obtained. By the method, the stability of the hydrocracking products can be obviously improved.

Description

technical field [0001] The invention relates to a method for prolonging the quality stability of hydrocracking products, in particular to a method for prolonging the quality stability of heavy naphtha products in late hydrocracking products during long-term 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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