Abstract: The sulfur content of hydrogenated wax oil and the first bed pressure difference of the reactor in the 3.2 MM TPY wax oil hydrotreating unit of a company continued are rising. At the end of the operation, the processing load decreases to 340 t/h, the reaction temperature increases to 413 ℃, the sulfur mass fraction of hydrogenated wax oil continues to be higher than 0.5% (the design value is less than 0.35%), and the pressure difference of the first bed of the reactor is 0.35 MPa (the design value is less than 0.3 MPa).In order to avoid further corrosion of downstream units and the damage of reactor internals in wax oil hydrotreating unit, the unit is shut down after 43 months of operation. Through the discussion and analysis of the catalyst deactivation, pressure drop rise of the first bed, internal leakage of the high-pressure exchanger, some measures are put forward, such as strengthening the management of feedstock, stabilizing the process operation, optimizing the bed temperature distribution, optimizing the catalyst grading and adjusting the reaction severity according to the metal deposition, so as to ensure the long-term operation of the unit, meet the requirements of repair every four years, avoid shutdown during operation.

Key words: wax oil hydrogenation unit, long period operation, feedstock properties, reaction temperature, reactor pressure drop

摘要： 某公司3.2 Mt/a蜡油加氢处理装置加氢蜡油硫含量及反应器第一床层压差持续上升,运行末期加工负荷降至340 t/h,反应温度升至413 ℃,加氢蜡油硫质量分数持续高于0.5%(设计值小于0.35%),反应器第一床层压差0.35 MPa(设计值小于0.3 MPa)。为避免下游装置腐蚀加剧及反应器内构件损伤,装置运行43个月后进行停工撇头。对催化剂失活、第一床层压力降上涨、高压换热器内漏等问题进行了探讨分析,提出了强化原料油管理、稳定工艺操作、改善床层温度分布、优化催化剂级配以及根据金属沉积量调整反应苛刻度等措施,保障了装置长周期运行,满足了“四年一修”的需求,避免了装置运行期间停工撇头。

关键词: 蜡油加氢装置, 长周期运行, 原料油性质, 反应温度, 反应器压力降