Abstract: The hydrocracking technology of increasing jet fuel and high quality tail oil in large proportion and the long-term industrial application of supported catalyst in a 2.0 Mt/a high pressure hydrocracking unit were introduced. The production situation of blending different secondary processing oil and using flexible hydrocracking catalyst in the previous cycle were compared. The results of initial and mid-term industrial calibration showed that the yield of kerosene fraction was more than 40% with the smoke point more than 25 mm, and BMCI of tail oil fraction was less than 9. After continuous operation for 57 months, the products had excellent properties, and the goals of increasing kerosene fraction in large proportion was successfully achieved, improving the quality of tail oil and flexible production of diesel fuel. The catalyst bed temperature, bed pressure drop and radial temperature difference increased slowly, which showed that the catalyst had good activity stability, low temperature raising rate and strong impact resistance, which could meet the needs of long-term operation. The successful application of the new technology in the unit has guaranteed the supply of jet fuel supply in the capital area, provided technical support for transformation and development of the refinery, integration of refining and chemical industry, maximization of benefits, and provided high-quality raw materials for ethylene unit.

Key words: hydrocracking, jet fuel, tail oil