渣油加氢装置运行中存在问题及措施

Operation problems of residue hydrotreating unit and countermeasures

对某炼油化工有限公司3.1 Mt/a高苛刻度渣油加氢装置工艺特点进行了介绍。分析了投产以来影响装置增加运行周期的径向温差大、分馏塔结盐严重和原料自动反冲洗过滤器冲洗频繁问题。指出反应器入口分配器"容垢"能力不足是径向温差大的主要原因;轻烃中Cl-和NH4+生成的NH4Cl析出结晶是导致分馏塔结盐的主要原因。针对这些问题分别采取了更换反应器入口分配器、采用蒸汽吹塔降低塔盘结盐对石脑油干点超标的影响、增上原料预过滤器等改造措施,并提出继续改进的思路和方法。采取措施后,装置脱硫率在80%左右,残炭脱除率在40%左右,金属脱除率在60%左右,催化剂效能得到最大限度的发挥。

The process features of the 3.1 MM TPY high-severity residue hydrotreating unit of a refining ＆ chemical company are introduced. The problems of large radial temperature difference which affects the op-erating cycle of the unit, the serious salt deposition in fractionator and the frequent flushing of automatic back- washing filter after start-up are analyzed. It is pointed out that the insufficient fouling tolerance of reactor inletdistributor is tile culprit of large radial temperature difference. The crystallization of NH4C1 from C1- andNH4＋ leads to salt deposition in fractionator. To solve these problems, the following measures have been taken： the reactor inlet distributor is replaced, the fractionator is flushed with steam to minimize the impact of salt deposition on tower tray on off-specifications of naphtha end point, and feed filter is installed. In addition, continuous improvements have been made. After taking these measures, sulfur removal rate is maintained at about 80%, the carbon residue removal rate is about 40%, the metal removal rate is about 60%, and the catalyst performances have been maximally utilized.