Startup passivation method of hydrocracking catalyst

Abstract

The invention discloses a startup passivation method of a hydrocracking catalyst. The method comprises: after the end of vulcanization, lowering the temperature of a refining reactor inlet and a cracking reactor inlet to 220-270DEG C and 150-205DEG C respectively; introducing high nitrogen oil into a refining reactor, leaving the refining effluent to enter a thermal high-pressure separator to perform separation, and passing the gas obtained in the thermal high-pressure separator through a hydrocracking reactor; maintaining a constant cracking reactor inlet temperature, and gradually raising the refining reactor inlet temperature; when the ammonia concentration of acidic water from a cold high-pressure separator is greater than or equal to 0.1wt%, slowly raising the cracking reactor inlet temperature through heat exchange till 310-330DEG C, thus coming to the end of startup passivation. According to the invention, the high nitrogen raw material is introduced into a refining segment at the catalyst passivation stage, and the ammonia gas generated by hydrogenation of the high nitrogen raw material is adopted as a passivant to passivate a cracking agent, thus realizing the purpose of no need of using a passivant. The method provided in the invention is applicable to the startup passivation processes of various hydrocracking catalysts.

Description

technical field [0001] The invention relates to a start-up passivation method of a molecular sieve hydrocracking catalyst, which mainly uses raw material oil containing relatively high nitrogen content as a passivator to passivate the hydrocracking agent, so as to achieve the purpose of not using a passivator , the principle of starting passivation process applicable to various types of hydrocracking catalysts. 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 core of the process of conversion into target products such as light oil and middle distillate oil is the hydrocracking catalyst. If classified according to the carrier, it can be divided into amorphous catalyst and molecular sieve catalyst. The carrier of amorphous catalyst ...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the problems existing in the existing start-up technology, the present invention provides a start-up method for passivating the sulfided hydrocracking agent by using a raw material containing higher nitrogen content as a passivating agent. The method utilizes hydrogenation denitrogenation The ammonia gas generated by the reaction is adsorbed on the cracking agent, the passivation process is completed and the start-up is successful, which can completely avoid the consumption of the passivation agent during the start-up process, which not only saves energy, but also reduces the pollution of the passivation agent to the environment and the impact on the environment. harm to the human body, and at the same time, it can produce high-quality refined steam, diesel, wax and other products for blending or providing feed for downstream devices

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