Abstract: The catalyst deactivation rate of diesel hydrogenation unit producing Guo Ⅴ and Guo Ⅵ diesel was significantly higher than that of producing Guo Ⅳ diesel, and the operation cycle of the unit was limited. In view of these problems, SINOPEC Dalian Research Institute of Petroleum and Petrochemicals systematically studied the influence of the dry point of feedstock, nitrogen content and the proportion of secondary processing diesel on the ultra-deep desulfurization of diesel. The suggestions about the dry point of diesel, the proportion of secondary processing diesel and the selection of catalyst were provided to ensure long-term stable operation of the unit. The results showed that in order to extend the operation cycle of diesel hydrogenation unit, it was necessary to control the dry point of straight run diesel no higher than 370 ℃, coking diesel no higher than 350 ℃, FCC diesel no higher than 360 ℃, and the total proportion of coking diesel and FCC diesel should be controlled below 35%. According to different diesel composition and actual working conditions of the unit, the appropriate catalyst and gradation should be selected in order to ensure the long-term stable operation of the diesel hydrogenation unit.

Key words: diesel hydrogenation unit, long-term operation, ultra-deep desulfurization, reaction temperature, dry point, nitrogen content, secondary processing oil

摘要： 针对柴油加氢装置生产国Ⅴ和国Ⅵ柴油时催化剂失活速率显著高于生产国Ⅳ柴油及装置运行周期受限的问题,中国石油化工股份有限公司大连石油化工研究院系统研究了原料油干点、氮含量及二次加工柴油比例等对柴油超深度脱硫的影响,并对柴油原料的干点、二次加工柴油比例的控制及提高装置稳定运行的催化剂选择等提出优化建议。研究表明,要延长柴油加氢装置运行周期,需要控制直馏柴油干点不高于370 ℃,焦化柴油干点不高于350 ℃,催化裂化柴油干点不高于360 ℃,且焦化柴油和催化裂化柴油总的比例最好控制在35%以下,同时根据不同柴油组成结合装置实际工况条件,选择合适的催化剂及级配技术,以确保柴油加氢装置长周期稳定运行。

关键词: 柴油加氢装置, 长周期运行, 超深度脱硫, 反应温度, 干点, 氮含量, 二次加工油品