催化汽油加氢脱硫装置国Ⅴ升级改造设计

Revamp design of the FCC gasoline hydrodesulfurization unit to upgrade to national V gasoline

关键词:  催化裂化汽油  加氢脱硫  国V汽油标准  改造 

Key words:  FCC gasoline  hydrodesulfurization  the national V gasoline standard  revamp

摘要:

某炼厂已投产的90×10⁴ t/a催化汽油加氢脱硫装置原设计为满足国Ⅳ汽油标准的要求而建。同时,为了应对汽油升级步伐的加快,使其将来可以平稳过渡至国Ⅴ汽油生产,设计中兼顾了国Ⅴ汽油的生产工况。其主体设备如反应器、加热炉采用“一步到位”的设计方法,而循环氢压缩机和新氢压缩机则根据机型的大小分别采取了“预留位置”和“一步到位”的设计方法。由此,不仅可满足目前的生产要求,也为将来国Ⅴ汽油的顺利升级奠定了基础。但由于加工原油的品种发生了变化,在进行国Ⅴ汽油升级改造时,催化汽油的硫质量分数由150×10-6升高至200×10-6,分馏塔的切割比例与原设计国Ⅴ工况相比由4∶6变成了3.5∶6.5。结合新国Ⅴ工况下操作条件的变化及实际装置运行过程中遇到的问题,对该装置进行了增加1台加氢后处理反应器、增加1台循环氢压缩机、更换加热炉燃烧器、更换循环氢脱硫塔塔盘以及冷换设备等措施,顺利完成本次改造。 

Abstract:

An FCC gasoline hydrodesulfurization unit of 0.9 Mt/a in a refinery was designed to meet the national Ⅳgasoline standard. In order to reach the national V gasoline standard in the future, the main equipments such as reactor and furnaces were designed to satisfy the the national Ⅳgasoline standard. The recycle hydrogen compressor was designed to satisfy the national Ⅳ gasoline standard and the place was reserved taking the national V case into consideration while the hydrogen make-up compressor was designed to satisfy the national V gasoline standard just by one-step. The orginal design was not only to meet the national standard of gasoline Ⅳ but also laid a foundation to the smooth transition to the national standard of gasoline V. Due to the change of crude oil variety, the sulfur mass fraction of FCC was increased from 150×10-6 to 200×10-6 when upgraded to the national V gasoline. The cut proportion of the fraction column was changed from 4∶6 to 3.5∶6.5. Based on the change of operating conditions and problems encountered in the actual operation process, the revamp of the unit was conducted by adding a new post-hydrotreating reactor and recycle hydrogen compressor, replacing the burners of heating furnace, the tower tray of recycle hydrogen desulfurization tower and the heat exchangers.