FCC装置沉降器结焦原因分析及防范措施

Analysis of Coking Causes and Preventive Measures for FCC Settler

针对某120 Mt/a重油催化裂化装置沉降器频繁结焦问题进行分析,不同位置的焦块组成分析表明,结焦的主要组成为催化剂细分和未汽化油,从结焦机理分析该装置的焦炭类型属于软焦。从工艺参数和设备结构两方面总结影响结焦的主要因素,包括原料性质不稳定、反应温度大幅度波动造成未汽化油增多、预提升干气用量不足、预提升套筒脱落以及粗旋出口和顶旋入口的软连接失效等。从优化原料性质和操作条件等方面提出一系列防结焦措施,可为催化裂化装置的长周期运行提供理论指导。

An analysis was conducted on the frequent coking problem in the settler of a 120 Mt/a heavy oil catalytic cracking unit.The composition analysis of coke blocks at different positions showed that the main components of coking were catalyst subdivision and non vaporized oil.From the coking mechanism analysis,the coke type of the unit belongs to soft coke.The insufficient amount of pre-lifting dry gas is the main cause of the coking of the settler.A series of preventive measures are put forward from the aspects of raw materials properties and operating conditions to reduce the coking of the settler and ensure the long-term operation of the catalytic cracking unit.