Start-up method of hydrocracking unit

Abstract

The invention relates to a starting method of a hydrocracking unit. A reaction zone of the hydrocracking unit is filled with an oxidation type hydrogenation catalyst. The starting method comprises steps of heating circulating gas to (150-225)+ / -15 DEG C, introducing a sulfurizing agent, performing sulfuration at a constant temperature of 230+ / -15 DEG C, heating continuously to raise the temperature to 370+ / -20 DEG C and performing sulfurization at the constant temperature, introducing low-nitrogen starting oil when the temperature decreases to 150+ / -15 DEG C after the catalyst sulfurization is finished, raising the temperature to 210+ / -20 DEG C and introducing nitrogen-containing light distillate oil, introducing nitrogen-containing heavy distillate oil instead when the temperature is 290+ / -15 DEG C or higher, introducing raw oil instead step by step when the temperature is 320+ / -15 DEG C and shifting to normal production. Compared with the prior art, the starting method replaces anhydrous liquid ammonia by the nitrogen-containing distillate oil and the starting process is smooth and steady.

Description

technical field [0001] The invention belongs to a processing method of oil refining technology, in particular to a hydrocracking unit wet start-up method. Background technique [0002] With the increasingly stringent environmental regulations around the world, there is an increasing demand for clean, light, and clean fuels. Hydrogenation technology is an effective means of producing clean products. Therefore, hydrogenation units have become the standard configuration of refineries. The number of hydrogenation units is increasing. [0003] Hydrocracking technology is a kind of hydrogenation technology, and it is one of the important means to process heavy distillate oil into clean products. Hydrocracking technology generally uses vacuum distillate oil or similar distillate oil as raw material to produce high-quality Naphtha, aviation kerosene and diesel oil, while hydrocracking tail oil is also a high-quality raw material for steam cracking to ethylene and isomerization dewa...

AI Technical Summary

Problems solved by technology

CN201010222031.3 discloses a hydrocracking unit start-up method, wherein the hydrocracking pretreatment catalyst is selected as the second type of active center type, and the hydrocracking catalyst is selected as the oxidized type, and the wet sulfidation start-up method is used at low temperature, and the dry method is used at high temperature Vulcanization method, the start-up process is complicated, and anhydrous liquid ammonia is required for catalyst passivation